Hibernate : Core Concept

Note:-

This tutorial expects the user have knowledge of both Java and SQL. If you have a limited knowledge of JAVA or SQL, it is advised that

you start with a good introduction to that technology prior to attempting to learn Hibernate.

Hibernate Framework

Hibernate framework simplifies the development of java application to interact with the database. Hibernate is an open source,

lightweight, ORM (Object Relational Mapping) tool. An ORM tool simplifies the data creation, data manipulation and data access. It is a

programming technique that maps the object to the data stored in the database.

Java Application ---- object----ORM----Database

The ORM tool internally uses the JDBC API to interact with the database.

Advantages of Hibernate Framework:-

There are many advantages of Hibernate Framework. They are as follows:

1)Opensource and Lightweight: Hibernate framework is opensource under the LGPL license. The open source GNU
LGPL(Lesser General Public License) is sufficiently flexible to allow the use of Hibernate in both open source and commercial projects.

2) Fast performance: The performance of hibernate framework is fast because cache is internally used in hibernate framework.
There are two types of cache in hibernate framework first level cache and second level cache. First level cache is
enabled bydefault.

3) Database Independent query: HQL (Hibernate Query Language) is the object-oriented version of SQL. It generates the database
independent queries. So you don't need to write database specific queries. Before Hibernate, If database is changed for the project,
we need to change the SQL query as well that leads to the maintenance problem.

4) Automatic table creation: Hibernate framework provides the facility to create the tables of the database automatically. So there is
no need to create tables in the database manually.

5) Simplifies complex join: To fetch data form multiple tables is easy in hibernate framework.

6) Provides query statistics and
database status: Hibernate supports Query cache and provide statistics about query and database status.

Hibernate Architecture:-

The Hibernate architecture includes many objects persistent object, session factory, transaction factory, connection factory, session,
transaction etc.

There are 4 layers in hibernate architecutre java application layer, hibernate framework layer, backhand api layer and database layer.
The high level architecture of Hibernate with mapping file and configuration file.

Hibernate framework uses many objects session factory, session, transaction etc. alongwith existing Java API such as JDBC
(Java Database Connectivity), JTA (Java Transaction API) and JNDI (Java Naming Directory Interface).

Core Object Of Hibernate:-

1-SessionFactory

2-Session

3-Transaction

4-ConnectionProvider

5-TransactionFactory

SessionFactory

The SessionFactory is a factory of session and client of ConnectionProvider. It holds second level cache.(optional) of data

. The org.hibernate.SessionFactory interface provides factory method to get the object of Session. You configure Hibernate's

SessionFactory. SessionFactory is a global factory responsible for a particular database. If you have several databases, for easier

startup you should use several configurations in several configuration files.

Session

The session object provides an interface between the application and data stored in the database. It is a short-lived object and wraps

the JDBC connection. It is factory of Transaction, Query and Criteria. It holds a first-level cache (mandatory) of data. The

org.hibernate.Session interface provides methods to insert, update and delete the object. It also provides factory methods for

Transaction, Query and Criteria.

Transaction

The transaction object specifies the atomic unit of work. It is optional. The org.hibernate.Transaction interface provides methods for

transaction management.

ConnectionProvider

It is a factory of JDBC connections. It abstracts the application from DriverManager or DataSource. It is optional.

TransactionFactory

It is a factory of Transaction. It is optional.

Steps to create A sample Example Of Hibernate (Without Using Annotation):-

Software requirement:-

1-Jdk 1.6 2-Eclipse Any Updated Version(I have Used here Eclipse Helios 3.6) 3-Hibernate Library 4-MySql DataBase

Step-1:-

First Download the hibernate jar from http://sourceforge.net/projects/hibernate/files/hibernate3/ Set it to Java build classpath (If You

Are Using the Eclipse.):-as Sample Project->right click->Properties->Java Bulid Path->Libraries->Add External JARs->ok.

Steps- 2:-

Now Create Entity Class (The Class which contains data,meta data which is to stored in to database Here )Here UserDetails.java which Is given below:-

package com.developerstpoint.jeetendra.hibernate; public class UserDetails { private int id; /** * @return the id */ public int getId() { return id; } /** * @param id the id to set */ public void setId(int id) { this.id = id; } private String name; private String address; /** * @return the name */ public String getName() { return name; } /** * @param name the name to set */ public void setName(String name) { this.name = name; } /** * @return the address */ public String getAddress() { return address; } /** * @param address the address to set */ public void setAddress(String address) { this.address = address; } }

Step 3:-

Now Create UserDetails.hbm.xml file where we configured data ,metadata attributes name of Table name where our data has to be stored in database. As given belows. This file should be in classpath or in side the src folder:-

<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="com.developerstpoint.jeetendra.hibernate.UserDetails" table="UserDetails2"> <id name="id"> <generator class="increment"/> </id> <property name="name"/> <property name="address"/> </class>

Step 4:-

Now Create An Schema in MySql database(since here I am using MySql database), Here I have created hibernatesample schema.

Step 5:-

Now Create a Configuration File hibernate.cfg.xml, where I have configured database configuration and mapping file UserDetails.hbm.xml. which is given below:-

<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!-- Database connection settings --> <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.url">jdbc:mysql://localhost:3306/hibernatesample</property> <property name="connection.username">username</property> <property name="connection.password" >password</property> <!-- JDBC connection pool (use the built-in) --> <property name="connection.pool_size">1</property> <!-- SQL dialect --> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <!-- Disable the second-level cache --> <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> <!-- Echo all executed SQL to stdout --> <property name="show_sql">true</property> <!-- Drop and re-create the database schema on startup --> <property name="hbm2ddl.auto">update</property> <mapping resource="UserDetails.hbm.xml"/> </session-factory> </hibernate-configuration>

Step 6:-

Now create the main class For Hibernate like given below:-

/** * */ package com.developerstpoint.jeetendra.hibernate; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.AnnotationConfiguration; import org.hibernate.cfg.Configuration; /** * @author jeetendra * */ public class HibernateTest { public static void main(String...hib){ UserDetails user=new UserDetails(); UserDetails user2=new UserDetails(); UserDetails user3=new UserDetails(); user.setAddress("BTM"); user.setName("Jeetendra"); user2.setAddress("BTM"); user2.setName("Jeetendra"); user3.setAddress("BTM"); user3.setName("Jeetendra"); SessionFactory sessionfactory=new Configuration().configure("hibernate.cfg.xml").buildSessionFactory(); Session session= sessionfactory.openSession(); session.beginTransaction(); session.save(user); session.save(user2); session.save(user3); session. getTransaction().commit(); } }

Now Run The main Class of Hibernate.java as here is HibernateTest.java Then Check the schema Definatly You will find Datas stored in Schema configured in .cfg file.

Steps to create A sample Example Of Hibernate (Using Annotation):-

Software requirement:-

1-Jdk 1.6 2-Eclipse Any Updated Version(I have Used here Eclipse Helios 3.6) 3-Hibernate Library 4-MySql DataBase

Step-1:-

First Download the hibernate jar from http://sourceforge.net/projects/hibernate/files/hibernate3/ Set it to Java build classpath (If You

Are Using the Eclipse.):-as Sample Project->right click->Properties->Java Bulid Path->Libraries->Add External JARs->ok.

Steps- 2:-

Now Create Entity Class (The Class which contains data,meta data which is to stored in to database Here )Here UserDetails.java which Is given below:-

package com.developerstpoint.jeetendra.hibernet; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; @Entity public class UserDetails { @Id @GeneratedValue private int id; private String name; private String address; /** * @return the id */ public int getId() { return id; } /** * @param id the id to set */ public void setId(int id) { this.id = id; } /** * @return the name */ public String getName() { return name; } /** * @param name the name to set */ public void setName(String name) { this.name = name; } /** * @return the address */ public String getAddress() { return address; } /** * @param address the address to set */ public void setAddress(String address) { this.address = address; } }

Step 3:-

Now Create An Schema in MySql database, Here I have created hibernatesample schema:-

Step 4:-

Now Create a Configuration File hibernate.cfg.xml, where I have configured database configuration and mapping file UserDetails.java which is given below. This file should be in classpath or in side the src folder:--

<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!-- Database connection settings --> <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.url">jdbc:mysql://localhost:3306/hibernatesample</property> <property name="connection.username">root</property> <property name="connection.password" >admin</property> <!-- JDBC connection pool (use the built-in) --> <property name="connection.pool_size">1</property> <!-- SQL dialect --> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <!-- Disable the second-level cache --> <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> <!-- Echo all executed SQL to stdout --> <property name="show_sql">true</property> <!-- Drop and re-create the database schema on startup --> <property name="hbm2ddl.auto">update</property> <mapping class="com.developerstpoint.jeetendra.hibernet.UserDetails" /> </session-factory> </hibernate-configuration>

Step 5:-

Now create the main class For Hibernate like given below:-

/** * */ package com.developerstpoint.jeetendra.hibernet; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.AnnotationConfiguration; import org.hibernate.cfg.Configuration; /** * @author jeetendra * */ public class HibernateTest { public static void main(String...hib){ UserDetails user=new UserDetails(); UserDetails user2=new UserDetails(); UserDetails user3=new UserDetails(); user.setAddress("BTMdddfdd"); user.setName("Jeetendra3dddfdfd33"); SessionFactory sessionfactory=new Configuration().configure("hibernate.cfg.xml").buildSessionFactory(); Session session= sessionfactory.openSession(); session.beginTransaction(); session.save(user); session. getTransaction().commit(); } }

Now Run The main Class of Hibernate.java as here is HibernateTest.java Then Check the schema Definatly You will find Datas stored in Schema configured in .cfg file.

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Checking the palindrome Of An given Integer/Reverse Integer

package com.developerstechpoint; import java.util.Scanner; public class PalindromNumber { public boolean checkPalindrom(){ System.out.println("Enter The Number Of Which U want to check for palindrom"); Scanner sc=new Scanner(System.in); int number=sc. nextInt(); int palindrom=number; int reverse=0,remainder; while(number!=0){ remainder=number%10; reverse=remainder+reverse*10; number=number/10; } System.out.println("Reversed Number is :"+reverse); if(palindrom==reverse){ return true; } else { return false; } } public static void main(String...palindrome){ if(new PalindromNumber().checkPalindrom()){ System.out.print("Number Is Palindrom"); }else{ System.out.println("Not Palindrom"); } } /* * Enter The Number Of Which U want to check for palindrom 125521 Reversed Number is :125521 Number Is Palindrom Enter The Number Of Which U want to check for palindrom 1254 Reversed Number is :4521 Not Palindrom * * */ }

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Copy the Text from one To another which file path given by command line argument

package com.developerstpoint.jeetendra; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.io.FileReader; import java.io.BufferedReader; import java.io.FileNotFoundException; import java.util.*; class FileIO { private static String st=""; public static void main(String[] args) { try{ FileReader fr=new FileReader(args[0]); FileWriter fw = new FileWriter(args[1]); BufferedReader br=new BufferedReader(fr); String s; while ((s = br.readLine()) != null){ String[] words = s.split(" "); for(String a: words){ StringBuilder builder=new StringBuilder(a); st+=builder.reverse().toString().concat(" "); //System.out.print(builder.reverse().toString().concat(" ")); } } System.out.println("scssd========"+st); fr.close(); fw.write(st); fw.close(); } catch(Exception e){ System.out.println(e); } } } /*Here args[0]=D:\IO\p2.txt and args[1]=D:\IO\p.txt which I have given * As Command Line Arguement as in Case of Eclipse I have Set these two file Path As * In menu oF Eclipse Run->Run Configurations ->Arguments-> like this * D:\IO\p2.txt D:\IO\p.txt then click Apply Button or If You can give these two path * on command line when You Are runnig the program through cmd. * * Here D:\IO\p2.txt is:- * hiiii my name is jeetendra . hiiii my name is jeetendra . Now OutPut Is :- D:\IO\p.txt is:- iiiih ym eman si ardneteej . iiiih ym eman si ardneteej . */

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Find the file with Special Extension from Folder

package com.developerstpoint.jeetendra; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.util.Scanner; public class FileWithSpecialExtension { public static void main(String...file) throws IOException{ String s=""; Scanner sc = new Scanner(System.in); System.out.println("Enter the Path Of Folder Where A number of File is stored with different Extension"); String inputpath = sc.nextLine(); File folder=new File(inputpath); File[] files=folder.listFiles(); for(int i=0; i<files.length; i++){ //System.out.println(files[i]); if(files[i].isFile()){ s=files[i].getName(); if(s.endsWith(".mp4")|| s.endsWith(".Mp4")|| s.endsWith(".MP4")|| s.endsWith(".mP4")){ System.out.println(s); }}}}} /* * Enter the Path Of Folder Where A number of File is stored with different Extension D:/Test Finger drawing - with OpenCV - YouTube.MP4 open source tracking software - YouTube.MP4 Track Mania driving script using python, opencv and java - YouTube.MP4 Video.MP4 W.mp4 */

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Find Unique And Frequent words of Input any file

package com.developerstpoint.jeetendra; import java.io.*; import java.util.*; class ToFindOutUniqueAndFrequentWords { public static void main(String[] unused) { Scanner in = new Scanner(System.in); // scanner object. int awords=0,uwords=0; try{ System.out.println("Enter your file name"); File inputfile = new File(in.nextLine()); Scanner words = new Scanner(inputfile); words.useDelimiter("[^A-Za-z]+"); HashMap<String,Integer> words_fre = new HashMap<String,Integer>(); while(words.hasNext()) { String s = words.next().toString(); awords++; // words count if(words_fre.containsKey(s)) { int a = words_fre.get(s); words_fre.put(s,a+1); } else { words_fre.put(s,1); uwords++; // unique words count } } Object[] key = words_fre.keySet().toArray(); Arrays.sort(key); for (int i = 0; i < key.length; i++) { System.out.println(key[i]+"= "+words_fre.get(key[i])); } System.out.println("Total Words = "+awords); System.out.println("Unique Words = "+words_fre.size()); }catch(IOException e) { System.out.println(e); } } } /*Enter your file name D:/JAVAProgram.txt Important= 1 Java= 1 com= 1 developerstpoint= 1 http= 1 program= 1 Total Words = 6 Unique Words = 6 Content of D:/JAVAProgram.txt is given Below:- // Important Java program http://developerstpoint.com/ */

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Find IP address And garbage Collection

For Grabage Collection:-

/** * */ package com.developerstechpoint; import static java.lang.System.*; /** * @author jeetendra * */ public class GarbageCollectionProgram { /** * @param args */ /* * This program performs garbage collection. * Free memory in java virtual machine is printed * and then garbage collection is done using gc method * of RunTime class, freeMemory method returns amount * of free memory in jvm, getRunTime method is used to get * reference of current RunTime object. */ public static void main(String s[]) throws Exception { Runtime rs = Runtime.getRuntime(); out.println("Free memory in JVM before Garbage Collection = "+rs.freeMemory()); rs.gc(); out.println("Free memory in JVM after Garbage Collection = "+rs.freeMemory()); }}

For IP Address:-

/** * */ package com.developerstechpoint; import java.net.InetAddress; import java.net.UnknownHostException; /** * @author jeetendra * */ public class GettingIPofMachine { /** * @param args * @throws UnknownHostException */ /* * This program prints IP or internet * protocol address of your computer system. * InetAddress class of java.net package is used, * getLocalHost method returns InetAddress object which represents local host. */ public static void main(String[] args) throws UnknownHostException { InetAddress inetaddress = InetAddress.getLocalHost(); System.out.println("LocalHost is : "+inetaddress); } }

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Sorting : Buble Sort

Bubble sort is a sorting algorithm that works by repeatedly stepping through lists that need to be sorted, comparing each pair of adjacent items and swapping them if they are in the wrong order. This passing procedure is repeated until no swaps are required, indicating that the list is sorted. Bubble sort gets its name because smaller elements bubble toward the top of the list.

Bubble Sort

Bubble sort is also referred to as sinking sort or comparison sort. Bubble sort has a worst-case and average complexity of O(n2), where n is the number of items sorted. Unlike the other sorting algorithms, bubble sort detects whether the sorted list is efficiently built into the algorithm. Bubble sort performance over an already sorted list is O(n).

/** * */ package com.developerstechpoint.sorting; import java.util.Scanner; /** * @author jeetendra * */ public class BubbleSort { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter The number of Array's Elements of which is to be sorted===>"); int number = sc.nextInt(); int array[]=new int[number]; System.out.println("Enter The "+number+ " Integer in the following Array===>"); for(int i=0; i<number; i++){ array [i] = sc.nextInt(); } // Sorting for(int i=0; i<(number-1); i++){ for(int j=0; j<number-i-1; j++){ int temp; if(array[j] > array[j+1]){ temp=array[j]; array[j]= array[j+1]; array[j+1]=temp; } } } String temp=""; for(int i=0; i<number; i++){ //System.out.println(array[i]); temp=temp+" "+array[i]; } System.out.println("Sorted Array is:"+"\n"+temp); } } /*Enter The number of Array's Elements of which is to be sorted===> 5 Enter The 5 Integer in the following Array===> 9 1 8 3 7 Sorted Array is: 1 3 7 8 9 * */

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Binary Tree ,Depth and Height

Step [1]:-

First Create Binary Tree class here is TreeNode.java which is given below:-

package com.developerstechpoint.Tree; public class TreeNode { /** * @author jeetendra * */ int data; TreeNode left; TreeNode right; TreeNode(int d){ data=d; left=null; right=null; } }

Step [2]:-

Create A class for all Its Methods like PreOrder,PostOrder,InOrder Traversal ,Depth and Height.Here class name is BinaryTreeMethods.java which is given below:-

package com.developerstechpoint.Tree; public class BinaryTreeMethods { /** * @author jeetendra * */ // Node insertion to create Binary Tree public void insertNode(TreeNode node,int data){ if(data < node.data){ if(node.left!=null){ insertNode(node.left, data); } else{ node.left=new TreeNode(data); } } else{ if(node.right!=null){ insertNode(node.right, data); } else{ node.right=new TreeNode(data); } } } //Pre-Order traversal of binary tree public void preOrder(TreeNode node){ if(node!=null){ System.out.println(node.data); preOrder(node.left); preOrder(node.right); } } //Post-Order traversal of binary tree public void postOrder(TreeNode node){ if(node!=null){ postOrder(node.left); postOrder(node.right); System.out.println(node.data); }} // In-Order traversal in binary tree public void inOrder(TreeNode node){ if(node!=null){ inOrder(node.left); System.out.println(node.data); inOrder(node.right); } } //Finding Depth and Height of the binary Tree public int BTreeHeight(TreeNode node){ if(node==null){ return 0; }else{ int left=BTreeHeight(node.left); int right=BTreeHeight(node.right); if(left>right){ return left+1; }else{ return right+1; } } } }

Step [3]:-Now Create Main class For the Tree As below:-

package com.developerstechpoint.Tree; import java.util.Scanner; public class BinaryTreeDepth { /** * @author jeetendra * */ /* The DEPTH of a node is the number of EDGES from the node to the tree's root node. and DEPTH is SAME as LEVEL of TREE. The HEIGHT of a node is the number of NODES on the longest path from the node to a leaf. For example, when looking at the root node of the tree, the depth would be 0 and the height would be the number of nodes on the longest path to a leaf. * */ public static void main(String[] args) { System.out.println("Enter The Data to insert into rootnode=>"); Scanner sc=new Scanner(System.in); int d=sc.nextInt(); TreeNode rootnode = new TreeNode(d); System.out.println(rootnode.data ); BinaryTreeMethods binarytmethods=new BinaryTreeMethods(); System.out.println("Enter The Number Of Elements You want to insert in Tree"); int number = sc.nextInt(); int i=1; while(i<=number){ System.out.println("Enter data to insert in tree==="); int insertiondata=sc.nextInt(); binarytmethods.insertNode(rootnode,insertiondata); i++; } binarytmethods.inOrder(rootnode); System.out.println("Pre-Order========================"); binarytmethods.preOrder(rootnode); System.out.println("Post-Order========================"); binarytmethods.postOrder(rootnode); int height=binarytmethods.BTreeHeight(rootnode); System.out.println("Depth of Binary Tree is===>"+(height-1)); System.out.println("Height of Binary Tree is======>"+height); } } /*output:- * Enter The Data to insert into rootnode=> 8 8 Enter The Number Of Elements You want to insert in Tree 5 Enter data to insert in tree=== 1 Enter data to insert in tree=== 4 Enter data to insert in tree=== 9 Enter data to insert in tree=== 76 Enter data to insert in tree=== 5 1 4 5 8 9 76 Pre-Order======================== 8 1 4 5 9 76 Post-Order======================== 5 4 1 76 9 8 Depth of Binary Tree is=======>3 Height of Binary Tree is==========>4 */

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LinkedList

Step [1]:-Create Node to create linked list as below:-

package com.javacoreconcept.jeetendra; public class Node { int data; Node next; Node(int d){ data=d; next=null; } }

Step [2]:-Now create to All Methods of Linked List:-

package com.javacoreconcept.jeetendra; import java.util.Scanner; public class MethodsLinkedList { Node head=null,tail = null; int size=0; Scanner sc=new Scanner(System.in); public void createList(int noOfNode){ int count=0; while(count<noOfNode){ System.out.println("Enter the data to create list====>"); int data=sc.nextInt(); Node newNode=new Node(data); if(head==null){ head=newNode; tail=head; size++; }else{ tail.next=newNode; tail=newNode; size++; } count++; } /*for(Node temp=head; temp!=null; temp=temp.next){ System.out.println(temp.data+" "+size); } */ } //Method to display data public void display(){ Node temp=head; while(temp!=null){ System.out.println(temp.data); temp=temp.next; } } //Adding Element At Nth Position public void nthpos(int pos, int data){ if(size<pos){ System.out.println("Length of linkedlist is less,Cant be entered the value"); } else{ Node temp1, temp2; temp1=head; for(int i=1; i<pos-1; i++){ temp1 = temp1.next; } temp2 = temp1.next; Node newNode2=new Node(data); temp1.next=newNode2; newNode2.next =temp2; } display(); } //Deleting Element From Nth position public void deletElementAtNthPos(int pos){ if(size<pos){ System.out.println("Length of linked List is less,Can't be deleted any value"); } else{ Node temp3=head; for(int i=1; i<pos-1; i++){ temp3=temp3.next; } //Node temp4=temp3.next; temp3.next=temp3.next.next; } display(); } }

Step [3]:-Now Create the mainClass to create LinkedList as Below:-

package com.javacoreconcept.jeetendra; import java.util.Scanner; public class LinkedList { /** * @param args */ public static void main(String[] args) { MethodsLinkedList methodlist=new MethodsLinkedList(); Scanner sc= new Scanner(System.in); System.out.println("How many nodes you want to create ?"); int n = sc.nextInt(); methodlist.createList(n); methodlist.display(); System.out.println("Enter the postion to add new node :"); int pos = sc.nextInt(); System.out.println("Enter data for new node :"); int data = sc.nextInt(); methodlist.nthpos(pos, data); System.out.println("Enter The Pos from where Data Has to be deleted"); int pos1 = sc.nextInt(); methodlist.deletElementAtNthPos(pos1); } }

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Transpose of Matrix

With help of Tranpose of Matrix we can also find out about the matrix whether it is symmetric or not . i.e. If Tranpose of matrix is equal to the matrix then Matrix is Called as Symmetric.

/** * */ package com.developerstechpoint.matrix; import java.util.Scanner; import static java.lang.System.*; /** * @author jeetendra * */ public class TransposeMatrics { /** * @param args */ /* * If A is an m × n order matrix then Transpose A is an n × m order matrix. */ public static void main(String...args){ Scanner sc = new Scanner (System.in); out.println("Enter the number for rows of Matrix"); int row = sc.nextInt(); out.println("Enter the number for column of Matrix"); int column = sc.nextInt(); int matrix [][] = new int[row][column]; int tranposematrix[][] =new int[column][row]; out.println("Enter The Element of Matrix"); for(int i=0; i< row; i++){ for(int j=0; j<column; j++){ matrix[i][j]=sc.nextInt(); }} out.println("Tranpose Of the Matrix=====>"); for(int i=0; i< row; i++){ for(int j=0; j<column; j++){ tranposematrix[j][i]=matrix[i][j]; } out.println(); } for(int i=0; i< column; i++){ for(int j=0; j<row; j++){ out.print(tranposematrix[i][j]+"\t"); } out.println(); } } } /*Enter the number for rows of Matrix 3 Enter the number for column of Matrix 1 Enter The Element of Matrix 1 2 3 Tranpose Of the Matrix=====> 1 2 3 */

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Multiplication Of Two Matrix

/** * */ package com.developerstechpoint.matrix; import java.util.Scanner; /** * @author jeetendra * */ public class MatrixMultiplication { /** * @param args */ public static void main(String[] args) { int sum1=0; Scanner sc =new Scanner(System.in); System.out.println("Enter the Rows of first matrix==>"); int rowfirst=sc.nextInt(); System.out.println("Enter the column of first matrix==>"); int columnfirst=sc.nextInt(); int first[][]=new int[rowfirst][columnfirst]; System.out.println("Enter the Elements of first matrix"); for(int i=0; i<rowfirst; i++){ for(int j=0; j<columnfirst; j++){ first[i][j]=sc.nextInt(); } } System.out.println("Enter the Rows of second matrix==>"); int rowsecond=sc.nextInt(); System.out.println("Enter the column of second matrix==>"); int columnsecond=sc.nextInt(); if(columnfirst!=rowsecond){ System.out.println("Multiplication can not be occured because of columnfirst and rowsecond is not equal"); } else{ int second[][]=new int[rowsecond][columnsecond]; System.out.println("Enter the Elements of second matrix"); for(int i=0; i<rowsecond; i++){ for(int j=0; j<columnsecond; j++){ second[i][j]=sc.nextInt(); } } int multiplicationresult[][]=new int[rowfirst][columnsecond]; System.out.println("Multiplication is :"); for(int i=0; i<rowfirst; i++){ for(int j=0; j<columnsecond; j++){ for(int k=0; k<rowsecond; k++){ sum1=sum1+first[i][k]*second[k][j]; } multiplicationresult[i][j]=sum1; sum1=0; } } for(int i=0; i<rowfirst; i++){ for(int j=0; j<columnsecond; j++){ System.out.print(multiplicationresult[i][j]+"\t"); } System.out.println(); } } } } /* * Enter the Rows of first matrix==> 2 Enter the column of first matrix==> 3 Enter the Elements of first matrix 1 2 3 4 5 6 Enter the Rows of second matrix==> 3 Enter the column of second matrix==> 2 Enter the Elements of second matrix 1 2 3 4 5 6 Multiplication is : 22 28 49 64 */ */

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Addition Of Two Matrix

/** * */ package com.developerstechpoint.matrix; import java.util.Scanner; import static java.lang.System.*; /** * @author jeetendra * */ public class MatrixAddition { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); out.println("Enter the number of row for matrix"); int row = sc.nextInt(); out.println("Enter the number of column for matrix"); int column = sc.nextInt(); int first[][] = new int[row][column]; int second[][] = new int[row][column]; int result[][] = new int[row][column]; out.println("Enter the data of first matrix"); for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ first[i][j]=sc.nextInt(); }} for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ out.print(first[i][j]+"\t"); } out.println(); } out.println("Enter the data for matrix second"); for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ second[i][j]=sc.nextInt(); }} for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ out.print(second[i][j]+"\t"); } out.println(); } out.println("addition or subtraction of these two matrix first and second"); for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ result[i][j]=first[i][j]+second[i][j]; }} for(int i=0; i<row; i++){ for(int j=0; j<column; j++){ out.print(result[i][j]+"\t"); } out.println(); } }} /* * Enter the number of row for matrix 1 Enter the number of column for matrix 3 Enter the elements of first matrix 1 2 3 1 2 3 Enter the data for matrix second 1 2 3 1 2 3 addition of these two matrix first and second 2 4 6 */

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Print all Substring of Input

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class FindingAllSubString { /** * @param args */ public static void main(String args[]) { String string, sub; int i, c, length; Scanner in = new Scanner(System.in); System.out.println("Enter a string to print it's all substrings"); string = in.nextLine(); length = string.length(); System.out.println("Substrings of \""+string+"\" are :-"); for( c = 0 ; c < length ; c++ ) { for( i = 1 ; i <= length - c ; i++ ) { sub = string.substring(c, c+i); System.out.println(sub); } } }}

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Check and Prime Number and Also Print The Prime Number

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class PrintPrimeNumberUpToTheInputNumber { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter the start number from where prime number has to checked and printed===>"); int start= sc.nextInt(); System.out.println("Enter the end number upto the , prime number has to checked and printed===>"); int end = sc.nextInt(); for(int i=start; i<=end; i++){ if(isPrime(i)){ System.out.println(i); } } } // Checking whether the given number prime or not private static boolean isPrime(int number) { if(number<1){ return false; } for(int i=2; i<number; i++){ if(number%i==0){ return false; } } return true; } }

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Fibonacci Series

package com.developerstechpoint.Tree; public class Fibonacci { // using recursion // public static int fib(int number){ // if(number==0){ // return 0; // // } // else if(number==1){ // return 1; // } // else{ // return fib(number-1)+fib(number-2); // } // } // /** * @param args */ public static void main(String[] args) { //Using Array int number[] =new int[10]; number[0]=0; number[1]=1; System.out.println(number[0]+"\n"+number[1]+"\n"); for(int i=2; i<10; i++){ number[i]=number[i-1]+number[i-2]; System.out.println(number[i]); } // Using For loop // System.out.println("Fibonacci series"); // for(int i=0; i<5; i++){ // System.out.println(fib(i));; // } // } //int first=0,second=1,next,i=0; // for(int i=0; i<10; i++){ // // // next=first+second; // first=second; // // second=next; // // System.out.println("======>"+next); // } // //Using Do While loop /* do{ next=first+second; first=second; second=next; i++; System.out.println("fibonacci series is :="+next); }while(i<10);*/ } }

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Comparision of Two String

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class CompareTwoString { /** * @param args */ /*This program compare strings i.e test whether * two strings are equal or not, compareTo method * of String class is used to test equality of two * String class objects. compareTo method is case * sensitive * i.e "java" and "Java" are two different strings if * you use *compareTo method. If you wish to compare strings but *ignoring *the case then use compareToIgnoreCase method. * *String 'hello' is greater than 'Hello' as ASCII value * of 'h' is greater than 'H'. To check two strings for * equality you can use equals method which returns true if * strings are equal otherwise false. */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter The first String "); String first = sc.nextLine(); System.out.println("Enter The second String "); String second = sc.nextLine(); if(first.compareTo(second)>0){ System.out.println("first String is greater than second"); } else{ if(first.compareTo(second)<0){ System.out.println("second String is greater than first "); } else{ System.out.println("Both Strings Are Equal "); } } } }

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Reverse String And Checking the Palindrom

package com.developerstechpoint; import java.util.Scanner; public class PalindromString { public boolean checkPalindrom(){ System.out.println("Enter The String Which to Be check for Palindrom"); Scanner sc=new Scanner(System.in); String input=sc.nextLine(); String reverse=input; String s = ""; //String arr[] = input.split(""); // for(int i=arr.length-1; i>0; i--){ // s=s+arr[i]; // // } for(int i=input.length()-1; i>=0; i--){ s=s+input.charAt(i); } System.out.println("reversed string is =======>"+s); if(reverse.equals(s)){ return true; }else{ return false; } } public static void main(String...palindrome){ PalindromString ps= new PalindromString(); if(ps.checkPalindrom()){ System.out.println("given String Is Palindrome"); }else{ System.out.println("given String is Not Palindrom"); } } } /*Enter The String Which to Be check for Palindrom malayalam reversed string is =======>malayalam given String Is Palindrome====> * * Enter The String Which to Be check for Palindrom jeetendra reversed string is =======>ardneteej given String is Not Palindrom * * * * */

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Floyed’s Triangle

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class FloyedTriangle { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter the number of rows or columns of the triangle"); int numberofrowsorcoloumsoftriangle = sc.nextInt(); int number = 1; for(int i = 1; i <= numberofrowsorcoloumsoftriangle; i++ ){ for(int j= 1; j<=i; j++){ /* System.out.print(i); will print if input will be 3:- 1 2 2 3 3 3 */ /*System.out.print(j); * will print if input will be 3:- 1 1 2 1 2 3 */ System.out.print(number+" "); number++; } System.out.println(); /* Output will be if input is 3:- 1 2 3 4 5 6 */ } } }

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Armstrong Number

package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ /*An Armstrong number of three digits is an integer such that the sum of the cubes of * its digits is equal to the number itself. For example, 371 is an Armstrong number since * 3**3 + 7**3 + 1**3 = 371. * * 1,153,370,371,407 etc are armstrong Number*/ public class ArmstrongNumber { public boolean checkNumberForArmstrong(){ Scanner sc=new Scanner(System.in); System.out.println("Enter The Number====>"); int numbertocheck=sc.nextInt(); int reverse=0; int armstrong=numbertocheck; while(armstrong!=0){ int remainder=armstrong%10; reverse=remainder*remainder*remainder+reverse; armstrong= armstrong/10; } if(numbertocheck==reverse){ return true; } else{ return false; } }public static void main(String...armstrong){ if(new ArmstrongNumber().checkNumberForArmstrong()){ System.out.println("Number Is Armstrong"); }else{ System.out.println("Not armstron"); }}}

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Find Factorial of Input Number

package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class FactorialOfGivenNumber { // public void fatorial(){ // Scanner sc=new Scanner(System.in); // System.out.println("Enter The No. Of which you want to print the Factorial"); // int number=sc.nextInt(); // int factorial=1; // for(int i=1; i<=number; i++){ // factorial=factorial*i; // // } // System.out.println("Factorial Of Number Is :"+factorial); // } ; //using Recursion public int factorial(int number){ if(number==1){ return 1; } else{ return number*factorial(number-1); }} public static void main(String...fact){ System.out.println("Enter the number Of which You want to create factorial using recursion"); Scanner sc=new Scanner(System.in); int number=sc.nextInt(); System.out.println(new FactorialOfGivenNumber().factorial(number)); } }

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Largest of three number

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class LargestNumberofThreeInteger { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter the first number====>"); int first = sc.nextInt(); System.out.println("Enter the second number====>"); int second = sc.nextInt(); System.out.println("Enter the third number====>"); int third = sc.nextInt(); if(first>second && second>third){ System.out.println("Largest number is : "+first); }else{ if(second>first && second>third){ System.out.println("largest number is: "+second); }else{ System.out.println("Largest number is :"+third); } } } }

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Swapping two number

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class SwappingNumber { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter the first number"); int first = sc.nextInt(); System.out.println("Enter the second number"); //without using third vaiable int second = sc.nextInt(); /* First logic * first =first *second; second=first/second; first=first/second; */ // Second logic first=first+second; second=first-second; first=first-second; System.out.println( "Your first number is :"+first+"\n"+" second number is :"+second); }}

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Farenheit to Celsius

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class FareinheitToCelsius { /** * @param args */ public static void main(String[] args) { float temperatue; Scanner in = new Scanner(System.in); System.out.println("Enter temperatue in Fahrenheit"); temperatue = in.nextFloat(); temperatue = (temperatue - 32)*5/9; System.out.println("Temperatue in Celsius = " + temperatue); } } /* output will be :- * Enter temperatue in Fahrenheit *98.6 *Temperatue in Celsius = 37.0 */

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Find odd or even number

/** * */ package com.developerstechpoint; import java.util.Scanner; /** * @author jeetendra * */ public class FindOddOrEven { /** * @param args */ public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter The number which is to be checked for Even Or Odd"); int number = sc.nextInt(); if(number%2==0){ System.out.println("Input Number Is Even Number"); } else{ System.out.println("Input Number Is An Odd Number"); } } }

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Printing of alphabet

/** * */ package com.developerstechpoint; /** * @author jeetendra * */ public class PrintingAlphabet { /** * @param args */ public static void main(String[] args) { for(char start='a'; start<='z'; start++){ System.out.print(start+" "); } //output will be :- // a b c d e f g h i j k l m n o p q r s t u v w x y z for(char start='A'; start<='z'; start++){ System.out.print(start+" "); System.out.println(""); } // output will be:- /*a b c d e f g h i j k l m n o p q r s t u v * w x y z A * B C D E F G H I J K L M N O P Q R S T U V W X Y Z * [ \ ] ^ _ ` a b c d e f g h i j k l m n o p q r s * t u v w x y z */ for(char start='z'; start>='A'; start--){ System.out.print(start+" "); } // output will be :- /*z y x w v u t s r q p o n m l k j i h g f e d c b a * ` _ ^ ] \ [ * Z Y X W V U T S R Q P O N M L K J I * H G F E D C B A * * * */ } }

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JSP : Core Concept

JSP :-Introduction

Jsp technology is used to web application like servlet.It can be thought as extension of servlet as it provides more functionality more than that of servlet like expression language,jstl etc. Life Cycle of JSP:

1- Translation

2- Compilation

3- Classloading(class file is loaded by classloader)

4- Instantiation(Object Of generated servlet is created )

5- Initialization( jspInit() method is invoked by container)

6- Request Processing( _jspService() method is invoked by container)

7- Destroy( jspDestroy() method is invoked by container)

Note: in _jspService() ,underscore points out that it can not be overrides.

Jsp scriptlet tag(Scriptlet Elements):-

1-scriptlet tag

2-expression tag

3-Jsp Declaration tag

1-scriptlet tag

This one is used to write the java source code.for eg. <% java source code %> <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <% out.print("welcome to jsp scriptlet tag example code"); %> </body> </html>

2-expression tag

This one replacement of output stream in case of servlet. <%= source code %> For eg..

<body> <%=("Hii")%> </body> Note:-

Basic Difference between Jsp declaration and expression tag. Jsp declaration tag only declare the variable and methods and most thing is the it is placed out side the _jspService() method so that it doesn’t memory get every time when service method is called.

For eg. <!-- Variable Declaration --> ..... <body> <%! String name="Jeetendra"; %> <%=("Hii ") +name %> </body> ..... <!-- Method Declaration --> ..... <body> <%! int cube(int n){ return n*n*n ; }%> <%="Cube of "+5+" is " +cube(5) %> </body> .....

JSP Standard Tag Library:-

The JSP Standard Tag Library represents a set of tags to simplify the JSP development.JSTL mainly 5 types of tags:-

1-core tags

2-Sql tags

3-xml tags

4-internationalization tags

5-Functions tags

The JSTL core tag provides variable support, URL management, Flow Control, etc.the url for the core tag is http://java.sun.com/jsp/jstl/core The prefix of the core tag is c.There are following jstl core tags that are given below:-

Tag	Description
<c:out >	Like <%= ... >, but for expressions.
<c:set>	Sets the result of an expression evaluation in a 'scope'
<c:remove >	Removes a scoped variable (from a particular scope, if specified).
<c:catch>	Catches any Throwable that occurs in its body and optionally exposes it.
<c:if>	Simple conditional tag which evalutes its body if the supplied condition is true.
<c:choose>	Simple conditional tag that establishes a context for mutually exclusive conditional operations, marked by and
<c:when>	Subtag of that includes its body if its condition evalutes to 'true'.
<c:otherwise >	Subtag of that follows tags and runs only if all of the prior conditions evaluated to 'false'.
<c:import>	Retrieves an absolute or relative URL and exposes its contents to either the page, a String in 'var', or a Reader in 'var Reader'.
<c:forEach >	The basic iteration tag, accepting many different collection types and supporting subsetting and other functionality .
<c:forTokens>	Iterates over tokens, separated by the supplied delimeters.
<c:param>	Adds a parameter to a containing 'import' tag's URL.
<c:redirect >	Redirects to a new URL.
<c:url>	Creates a URL with optional query parameters.

Snapshot of Code

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <c:import var="data" url="http://www.javatpoint.com/jstl"></c:import> <h2>Data Is</h2> <c:out value="${data}"></c:out> <c:catch var="g" > <% int i=29/0; %> </c:catch> <c:if test="${g!=null}"> <p>the exception. :${g.message}</p> </c:if> </body> .....

2-Sql tags:-

provides SQL support and its url is http://java.sun.com/jsp/jstl/sql The prefix of this tag is sql. The JSTL SQL tag library provides tags for interacting with relational databases (RDBMSs) such as Oracle, mySQL, or Microsoft SQL Server. Following is the syntax to include JSTL SQL library in your JSP:

<%@ taglib prefix="sql" uri="http://java.sun.com/jsp/jstl/sql" %>

Following is the list of SQL JSTL Tags:

Tag	Description
<sql:setDataSource>	Creates a simple DataSource suitable only for prototyping
<sql:query>	Executes the SQL query defined in its body or through the sql attribute.
<sql:update>	Executes the SQL update defined in its body or through the sql attribute.
<sql:param>	Sets a parameter in an SQL statement to the specified value.
<sql:dateParam>	Sets a parameter in an SQL statement to the specified java.util.Date value.
<sql:transaction >	Provides nested database action elements with a shared Connection, set up to execute all statements as one transaction.

3-xml tags:-

Provides Flow control and transformation etc. Its url is http://java.sun.com/jsp/jstl/xml The prefix is x. The JSTL XML tags provide a JSP-centric way of creating and manipulating XML documents. Following is the syntax to include JSTL XML library in your JSP. The JSTL XML tag library has custom tags for interacting with XML data. This includes parsing XML, transforming XML data, and flow control based on XPath expressions.

<%@ taglib prefix="x" uri="http://java.sun.com/jsp/jstl/xml" %>

Before you proceed with the examples, you would need to copy following two XML and XPath related libraries into your \lib: [1]- XercesImpl.jar: Download it from http://www.apache.org/dist/xerces/j/ [2]- xalan.jar: Download it from http://xml.apache.org/xalan-j/index.html Following is the list of XML JSTL Tags:

Tag	Description
<x:out>	Like <%= ... >, but for XPath expressions.
<x:parse>	Use to parse XML data specified either via an attribute or in the tag body.
<x:set >	Sets a variable to the value of an XPath expression.
<x:if >	Evaluates a test XPath expression and if it is true, it processes its body. If the test condition is false, the body is ignored.
<x:forEach>	To loop over nodes in an XML document.
<x:choose>	Simple conditional tag that establishes a context for mutually exclusive conditional operations, marked by and
<x:when >	Subtag of that includes its body if its expression evalutes to 'true'
<x:otherwise >	Subtag of that follows tags and runs only if all of the prior conditions evaluated to 'false'
<x:transform >	Applies an XSL transformation on a XML document

4-internationalization tags:-

Provides message formatting,number and date formatting etc. the url for this is http://java.sun.com/jsp/jstl/fmt and prefix is fmt. The JSTL formatting tags are used to format and display text, the date, the time, and numbers for internationalized Web sites. Following is the syntax to include Formatting library in your JSP:

<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>

Following is the list of Formatting JSTL Tags:

Tag	Description
<fmt:formatNumber>	To render numerical value with specific precision or format..
<fmt:parseNumber>	Parses the string representation of a number, currency, or percentage.
<fmt:formatDate>	Formats a date and/or time using the supplied styles and pattern
<fmt:parseDate>	Parses the string representation of a date and/or time
<fmt:bundle>	Loads a resource bundle to be used by its tag body.
<fmt:setLocale>	Stores the given locale in the locale configuration variable.
<fmt:message>	To display an internationalized message.
<fmt:timeZone>	Specifies the time zone for any time formatting or parsing actions nested in its body.

5-Functions tags:-

Provide for String manipulation and length url of this is http://java.sun.com/jsp/jstl/functions Its prefix is fn. JSTL includes a number of standard functions, most of which are common string manipulation functions. Following is the syntax to include JSTL Functions library in your JSP:

<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>

Following is the list of JSTL Functions:

Tag	Description
fn:contains()	Tests if an input string contains the specified substring.
fn:containsIgnoreCase()	Tests if an input string contains the specified substring in a case insensitive way.
fn:endsWith()	Tests if an input string ends with the specified suffix.
fn:indexOf()	Returns the index withing a string of the first occurrence of a specified substring.
fn:join()	Joins all elements of an array into a string.
fn:length()	Returns the number of items in a collection, or the number of characters in a string.
fn:split()	Splits a string into an array of substrings.
fn:startsWith()	Tests if an input string starts with the specified prefix.
fn:substring()	Returns a subset of a string.
fn:substringAfter()	Returns a subset of a string following a specific substring.
fn:toUpperCase()	Converts all of the characters of a string to upper case..

JSP implicit Objects:-

There are 9 implicit objects that are availabale for all jsp pages. A list of the 9 implicit objects are given below:

Object	Type
out	JspWriter.
request	HttpServletRequest
response	HttpServletResponse
config	ServletConfig
application	ServletContext
session	HttpSession
pageContext	PageContext.
Page	Object.
exception	Throwable.

JSP directives:

These are the message which tells to container how to translate a JSP page into the corresponding servlet. There are three type of directive:-

[1]-Page directive

[2]-Include directive

[3]-Taglib directive

[1]-Page directive:-

Page directive defines the attribute that apply an entire JSP page.

<%@ page attribute=”value”%> Like <%@ page import=”java.util.Date”%> <%= Today is=new Date();%>

Attributes of JSP pages are:-

[1]- import

[2]- contentType

[3]- extends

[4]- info

[5]- buffer

[6]- language

[7]- isELIgnored

[8]- isThreadSafe

[9]- autoFlush

[10] session

[11]- pageEncoding

[12]- errorPage

[13]- isErrorPage

[2]-include directive:-

this is used to include the contents of any resourcesit may be jsp file,html file or text file,since JSP page is translated only once so better to use static resources. <% include file=”resourcesName”%> <% include file=”header.html”%>

[3]-Taglib:-

The JavaServer Pages API allows you to define custom JSP tags that look like HTML or XML tags and a tag library is a set of user-defined tags that implement custom behavior. The taglib directive declares that your JSP page uses a set of custom tags, identifies the location of the library, and provides a means for identifying the custom tags in your JSP page. The taglib directive follows the following syntax:

<%@ taglib uri="uri" prefix="prefixOfTag" >

Where the uri attribute value resolves to a location the container understands and the prefix attribute informs a container what bits of markup are custom actions. You can write XML equivalent of the above syntax as follows:

<jsp:directive.taglib uri="uri" prefix="prefixOfTag" />

Check more detail related to taglib directive at Taglib Directive.

Example: suppose the custlib tag library contains a tag called hello. If you wanted to use the hello tag with a prefix of mytag,

your tag would be <mytag:hello> and it will be used in your JSP file as follows:

<%@ taglib uri="http://www.example.com/custlib" prefix="mytag" %> <html> <body> <mytag:hello/>

Advantage Of JSTL over JSP scriptlet tags:-

1- Automatic JavaBean Introspection Support-

if you consider that JSTL's expression language handles JavaBean introspection automatically—which means you don't need to downcast objects you retrieve as scoped attributes—

<% if ((User)session.getAttribute("user")).getName().equals("jeetendra") { %> ... <% } %> Because of JSP's automatic support of JavaBean introspection, this block of code becomes much more simple in JSTL. <c:if test="${user.name == 'jeetendra'}"> ... <% } %>

2-Standardized Support for Formatting and I18N:-

In proper Web design, JSP pages should be responsible only for the presentation of data. Two very common components to this presentation are the formatting of numbers and strings, and internationalization (I18N) support. Prior to JSTL, there was no official way to support these two features in JSP scriptlet code. Many companies developed their own sets of objects that could be used to support multiple languages. Data formatting was handled in a similar fashion

JSP EL(Expression Languange):-

Expression Language (EL) makes it possible to easily access application data stored in JavaBeans components. JSP EL allows you to create expressions both (a) arithmetic and (b) logical. Within a JSP EL expression, you can use integers, floating point numbers, strings, the built-in constants true and false for boolean values, and null.

Simple Syntax:-

${expr}

Note :-

When the JSP compiler sees the ${} form in an attribute, it generates code to evaluate the expression and substitues the value of expresson.

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Struts2.x:Features And MVC Architecture

Struts 2 Framework:-

The struts 2 framework is used to develop MVC-based web application.Apache Struts is a free, open-source, MVC framework for creating elegant, modern Java web applications. The Struts 2 framework is used to develop MVC (Model View Controller) based web applications. Apache Struts 2 was originally known as WebWork 2. After working independently for several years, the WebWork and Struts communities joined forces to create Struts2. This new version of Struts is simpler to use and closer to how Struts was always meant to be.In Another word we can say that Struts 2 is the combination of webwork framework of opensymphony and struts1. struts2 = webwork + struts1 The Struts 2 provides supports to POJO based actions, Validation Support, AJAX Support, Integration support to various frameworks such as Hibernate, Spring, Tiles etc, support to various result types such as Freemarker, Velocity, JSP etc.

Note :-

OpenSymphony was an Open Source computer software project dedicated to providing enterprise class Java EE components. OpenSymphony shut down sometime around 2009-2011, but some of the subprojects are now maintained elsewhere. Patrick Lightbody was one of the main programmers at the company.

WebWork and XWork : Core Engine Of OpenSymphony

Struts 2 Features:-

Struts 2 provides many features that were not in struts 1. The important features of struts 2 framework are as follows:

[1]:-Configurable MVC components

In struts 2 framework, we provide all the components (view components and action) information in struts.xml file. If we need to change any information, we can simply change it in the xml file.

[2]:-POJO based actions

In struts 2, action class is POJO (Plain Old Java Object) i.e. a simple java class.

[3]:-AJAX support

Struts 2 provides support to ajax technology.

[3]:-Integration support

We can simply integrate the struts 2 application with hibernate, spring, tiles etc. frameworks.

[4]:-Various Result Types

We can use JSP, freemarker, velocity etc. technologies as the result in struts 2.

[5]:-Various Tag support

Struts 2 provides various types of tags such as UI tags, Data tags, control tags etc to ease the developement of struts 2 application.

[6]:-Theme and Template support

Struts 2 provides three types of theme support: xhtml, simple and css_xhtml. The xhtml is default theme of struts 2. Themes and templates can be used for common look and feel.

WorkFlow in Struts-2.x:-

Image Courtesy: struts.apache.org [1]-The normal lifecycle of struts begins when the request is sent from client. This results invoke the servlet container which in turn is passed through standard filter chain. [2]-The FilterDispatcher filter is called which consults the ActionMapper to determine whether an Action should be invoked. [3]-If ActionMapper finds an Action to be invoked, the FilterDispatcher delegates control to ActionProxy. [4]-ActionProxy reads the configuration file such as struts.xml. ActionProxy creates an instance of ActionInvocation class and delegates the control. [5]-ActionInvocation is responsible for command pattern implementation. It invokes the Interceptors one by one (if required) and then invoke the Action. [6]-Once the Action returns, the ActionInvocation is responsible for looking up the proper result associated with the Action result code mapped in struts.xml. [7]-The Interceptors are executed again in reverse order and the response is returned to the Filter (In most cases to FilterDispatcher). And the result is then sent to the servlet container which in turns send it back to client.

Once the Action returns, the ActionInvocation is responsible for looking up the proper result associated with the Action result code mapped in struts.xml. The result is then executed, which often (but not always, as is the case for Action Chaining) involves a template written in JSPor FreeMarker to be rendered. While rendering, the templates can use the Struts Tags provided by the framework. Some of those components will work with the ActionMapper to render proper URLs for additional requests.

Note :-

Action Chaining:- The framework provides the ability to chain multiple actions into a defined sequence or workflow. This feature works by applying a Chain Result to a given Action, and intercepting its target Action's invocation with a ChainingInterceptor. FreeMarker:- FreeMarker is a Java-based template engine that is a great alternative to JSP. FreeMarker is ideal for situations where your action results can possibly be loaded from outside a Servlet container. For example, if you wished to support plugins in your application, you might wish to use FreeMarker so that the plugins could provide the entire action class and view in a single jar that is loaded from the classloader.

All objects in this architecture (Actions, Results, Interceptors, and so forth) are created by an ObjectFactory. This ObjectFactory is pluggable. We can provide our own ObjectFactory for any reason that requires knowing when objects in the framework are created. A popular ObjectFactory implementation uses Spring as provided by the Spring Plugin.

MVC Architecture:-

Model The model represents the state (data) and business logic of the application. View The view module is responsible to display data i.e. it represents the presentation. Controller The controller module acts as an interface between view and model. It intercepts all the requests i.e. receives input and commands to Model / View to change accordingly

Disadvantage MVC Architecture:-

We need to write the controller code self. If we change the controller code, we need to recompile the class and redeploy the application

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Struts2.x: Core Component

Core Components Of Struts2.x :-

[1]- Interceptors

[2]- ValueStack

[3]- ActionContext

[4]- ActionInvocation

[5]- OGNL

[1]-Interceptors :-

Interceptor is an object that is invoked at the preprocessing and postprocessing of a request. In Struts 2, interceptor is used to

perform operations such as validation, exception handling, internationalization, displaying intermediate result etc.

Advantage of interceptors :-

Pluggable If we need to remove any concern such as validation, exception handling, logging etc. from the application, we don't need to

redeploy the application. We only need to remove the entry from the struts.xml file.

Struts 2 default Interceptors :-

There are many interceptors provided by struts 2 framework. We have option to create our own interceptors. The struts 2 default interceptors are as follows:

[1]- alias It converts similar parameters that have different names between requests.

[2]- chainIf it is used with chain result type, it makes the properties of previous action available in the current action.

[3]- cookie It adds a cookie to the current action.

[4]- createSession It creates and HttpSession object if it doesn't exists.

[5]- clearSession I It unbinds the HttpSession object.

[6]- execAndWait It sends an intermediate waiting page for the result.

[7]- exception It maps exception to a result.

[8]- fileUpload It provides support to file upload in struts 2.x

[9]- i18n It provides support to internationalization and localization.

[10]- i18n It provides support to internationalization and localization.

[11]- logger It outputs the action name.

[12]- params It populates the action properties with the request parameters.

[13]- roles It supports role-based action.

[14]- scope It is used to store the action state in the session or application scope.

[15]- servletConfig It provides access to maps representing HttpServletRequest and HttpServletResponse.

[16]- staticParams It maps static properties to action properties.

[17]- timer It outputs the time needed to execute an action.

[18]- validation It provides support to input validation.

[19]- workflow It calls the validate method of action class if action class implements Validateable interface.

[2]- Struts2 ValueStack :-

A valueStack is simply a stack that contains application specific objects such as action objects and other model object. At the

execution time, action is placed on the top of the stack. We can put objects in the valuestack, query it and delete it. The value stack

can be accessed via the tags provided for JSP, Velocity or Freemarker. There are various tags which we will study in separate

chapters, are used to get and set struts 2.0 value stack. You can get valueStack object inside your action as follows:

ActionContext.getContext().getValueStack()

[3]- ActionContext :-

The ActionContext is a container of objects in which action is executed. The values stored in the ActionContext are unique per

thread (i.e. ThreadLocal). So we don't need to make our action thread safe. We can get the reference of ActionContext by calling

the getContext() method of ActionContext class. It is a static factory method. For example:

ActionContext context = ActionContext.getContext();

[4]- ActionInvocation :-

The struts framework provides ActionInvocation interface to deal with ActionInvocation. It provides many methods, some of them can be used to get the instance of ValueStack, ActionProxy, ActionContext, Result etc. The ActionInvocation represents the execution state of an action. It holds the action and interceptors objects.

[5]-OGNL :-

The Object-Graph Navigation Language (OGNL) is a powerful expression language that is used to reference and manipulate data on the ValueStack. OGNL also helps in data transfer and type conversion. The OGNL is very similar to the JSP Expression Language. OGNL is based on the idea of having a root or default object within the context. The properties of the default or root object can be referenced using the markup notation, which is the pound symbol(#). [The symbol (#) for a pound as a unit of weight..] As mentioned earlier, OGNL is based on a context and Struts builds an ActionContext map for use with OGNL. The ActionContext map consists of the following:-

application - application scoped variables

session - session scoped variables

root / value stack - all your action variables are stored here

request - request scoped variables

parameters - request parameters

atributes - the attributes stored in page, request, session and application scope

It is important to understand that the Action object is always available in the value stack. So, therefore if your Action object has properties x and y there are readily available for you to use. Objects in the ActionContext are referred using the pound symbol(#), however, the objects in the value stack can be directly referenced, for example if employee is a property of an action class then it can ge referenced as follows:

<s:property value="name"/>

instead of

<s:property value="#name"/>

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Struts 2.x: Configuration File

The struts application contains two main configuration files struts.xml file and struts.properties file.The struts.properties file is

used to override the default values of default.xml file provided by struts framework. So it is not mandatory. Mostly, you will not use

struts.properties file. We will learn about it later.Here, we are going to learn all about struts.xml file. First of all let us see the simple

example of struts.xml file.

1:- package element

We can easily divide our struts application into sub modules. The package element specifies a module. You can have or or more

packages in the struts.xml file.

Attributes of package element:-

[a]-  name is must for defining any package.

[b]-  namespace is an optional attribute of package. If namespace is not present, / is assumed as the default namespace. In such

case, to invoke the action class, you need this URI:    /actionName.action

If you specify any namespace, you need this URI:    /namespacename/actionName.action

extends The package element mostly extends the struts-default package where interceptors and result types are defined. If you

extend struts-default, all the actions of this package can use the interceptors and result-types defined in the struts-default.xml file.

2:- action element

The action is the subelement of package and represents an action.

Attributes of action element:-

[a]:-name is must for defining any action.

[b]:-classclass is the optional attribute of action. If you omit the class attribute, ActionSupport will be considered as the

default action. A simple action may be as:

<action name="getName">

method It is an optional attribute. If you don't specify method attribute, execute method will

be considered as the method of action class. So this code:

<package name="anything" extends="struts-default">

3:- result element

It is the sub element of action that specifies where to forward the request for this action.

Attributes of result element:-

[a]-name is the optional attribute. If you omit the name attribute, success is assumed as the default result name.

[b]-type is the optional attribute. If you omit the type attribute, dispatcher is assumed as the default result type.

<result name="success">/success.jsp</result>

Why Struts 2.x???

Or

Difference between Struts1.x and Struts2.x

Let us see the component and functional differences between struts 1.x and struts 2.x

[a]- In struts 1.x front controller is ActionServlet while In 2.x front controller is FilterDispatcher.

[b]- In struts 1.x we have RequestProcessor class In 2.x we have Interceptors instead RequestProcessor will see about this

concept later just remember as of now.

[c]- In struts 1.x we have multiple tag libraries like, html, logic, bean..etc. In 2.x we do not have multiple libraries, instead we have

single library which includes all tags.

[d]- In struts 1.x the configuration file name can be [any name].xml and we used to place in WEB-INF-folder. In 2.x

the configuration file must be struts.xml only and this must be in classes folder or WEB-INF/Classes/.

[e]- In struts 1.x we have form beans and Action classes separately In 2.x form bean, Action classes are combindly given as

Action class only, of course we can take separately if we want .

[f]- In struts 1.x properties file must be configured in struts-config.xml. But in 2.x we need to configure our resource

bundle(s) in struts.properties file.

[g]- In struts 1.x we have programmatic and declarative validations only In 2.x we have annotations support too along

with programmatic and declarative validations.

Functional Differences:-

[a]:-In struts 1.x declarative validations are done by using validation frame work. In 2.x , declarative validations are done by using

xwork2 frame work . [b]:- In struts 1.x an Action class is a singleton class, so Action class object is not a thread safe, as a

programmer we need to

make it as thread safe by applying synchronization In 2.x an Action class object will be created for each request, so it is by default

thread safe, so we no need to take care about safety issues here.

[c]:- In struts 1.x we have only jsp as a view technology while In 2.x we have support of multiple view technologies like velocity,

Freemarker, jasper reports, jsp etc.

[d]:- In struts 1.x Action class is having servlet dependency, because in execute() method accepts req,res parameter

right. In 2.x Action class doesn’t have any servlet dependency, because its execute() method doesn’t accepts any

parameters, however we can access all servlet objects with dependency injection .

Filename	Description
struts2-core.jar	Framework library itself, found in distribution root directory
xwork.jar	XWork 2 library on which Struts 2 is built (version 2.0 or later)
ognl.jar	Object Graph Navigation Language (OGNL), the expression language used throughout the framework
freemarker.jar	All UI tag templates are written in Freemarker (also a good option for your own views)
commons-logging.jar	Commons logging, which the framework uses to support transparently logging to either Log4J or JDK 1.4+
commons-fileupload.jar	The Commons FileUpload package makes it easy to add robust, high-performance, file upload capability to your servlets and web applications.
commons-io.jar	Commons IO is a library of utilities to assist with developing IO functionality.
web.xml	Java web application configuration file that defines the filters (and other components) for your web application
struts.xml	Framework configuration file that defines the actions, results, and interceptors for your application

Note:-

If any Struts 2 Plugins are included, then other JARs may be needed too. For example, the optional Spring Plugin requires the Spring JARs to be present.

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