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How to use JQuery dialog as Confirm dialog?

Posted by on Aug 14, 2015 in jQuery, jQuery UI | 0 comments

 
There are quite a few articles you might have read on SimpleCodeStuffs on jQuery like jQuery Tutorial for Beginners, AJAX implementation in Servlets using jQuery and jQuery UI etc.
 
This example will help you if you have any one of below queries:

  • How to implement “confirmation” dialog in jQuery UI dialog?
  • How to use jQuery UI dialog as JavaScript confirm BOX?
  • How to use JQuery dialog as Confirm dialog?
  • jQuery UI Replacement for alert()

Issue: How many times did you have to code some confirmation logic on your website to ensure that your users are sure about the action they are about to perform?
 
A typical example is prompting the user to confirm that they are sure about deleting a record. In typical/boring JavaScript world, you would do something like this:
 

HTML

 

<input type="submit" id="delete" value="Delete" onclick="javascript:deleteConfirmation();" />

 

Javascript

 

function deleteConfirmation() {  
    return confirm("Are you sure you want to delete this item?");
}

 
There is nothing wrong with this above code. However, it is plain. You cannot customize it with CSS make it look consistent with your site’s colour and identity.
 

jQuery to the rescue

 
jQuery UI has the solution for you. You can use the jQuery UI Dialog to present users with customized confirmation/dialog boxes as shown below.
 
jquery-confirm-dialog
 
Let’s see how to implement this
 

HTML

 
Firstly, let’s add the necessary jQuery libraries in the head section of the Jsp page.
 

<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="https://code.jquery.com/ui/1.11.2/themes/redmond/jquery-ui.css">
<script src="https://code.jquery.com/jquery-1.11.2.js"></script>
<script src="https://code.jquery.com/ui/1.11.2/jquery-ui.js"></script>
<!-- User Defined Js file -->
<script type="text/javascript">/js/confirmJs.js</script>
</head>
<body>
     <form method="post" action="delete.html">
	<input type="submit" class="button" id="Delete" name="Delete" value="Delete" />
     </form>
</body>
</html>

 

jQuery

 
File: confirmJs.js

$(document).ready(function(){
    $('#Delete').click(function(event) {
	event.preventDefault();
	var currentForm = $(this).closest('form');
	
	/** Create div element for delete confirmation dialog*/
	var dynamicDialog = $('<div id="conformBox">'+
	'<span class="ui-icon ui-icon-alert" style="float:left; margin:0 7px 20px 0;">'+
        '</span>Are you sure to delete the item?</div>');
	
	dynamicDialog.dialog({
		title : "Are you sure?",
		closeOnEscape: true,
		modal : true,
	
	       buttons : 
			[{
				text : "Yes",
				click : function() {
					$(this).dialog("close");
					currentForm.submit();
				}
			},
			{
				text : "No",
				click : function() {
					$(this).dialog("close");
				}
			}]
	});
	return false;
    });
}); 

 
The code above instantiates the dialog box and assigns it two buttons. The”Yes”and”No”buttons. The “Yes” is responsible for submitting the form to the server.
 

Other jQuery tutorial from our Blog

 

Reference

 
jQuery closest() Method
 

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Configuring & Adding Primary Key to Collections in Hibernate

Posted by on Jun 6, 2015 in Hibernate, Hibernate Annotation | 0 comments

Primary key in Hibernate
 
In previous article we learnt on how to persist a collection of objects of an entity class in a separate table using hibernate. And below are the following two tables are created in the database.
 
Hibernate_collection
 
1. STUDENT for Student entity type object
2. Student_lisOfAddress for Address value type object (The default table name for this table gets generated based on – Entity class name_Name of the embeddable object in the entity class).
Here ‘Student_ID’ column in Student_lisOfAddress is the foreign key reference of Student tables ‘ID’. In next article we shall learn to override the default collection class table name and to add primary key to it.
 
In this post we shall learn on how to change this default table name and foreign key name of collection table and how to add primary key to this table to identify each record separately.
 

Changing table name foreign key column name of collection table

 
To do this we need to add @JoinTable annotation before the collection in Entity class as show below.
 

@ElementCollection
@JoinTable(name="ADDRESS",joinColumns=@JoinColumn(name="STUDENT_ID"))
private Collection<Address> lisOfAddress = new ArrayList<Address>();

 
In parameter of @JoinTable table we specify name of table and name of joinColumns (i.e foreign key) with another annotation @JoinColumn. When you run the test program with the above changes, the following quires are displayed in eclipse console which have our overridden table name primary key name.
 

insert into STUDENT(COLLEGE, DEPARTMENT, NAME, ID) values (?, ?, ?, ?)
insert into ADDRESS(STUDENT_ID,CITY_NAME,PIN_CODE,STATE_NAME,STREET_NAME) values (?,?,?,?,?)
insert into ADDRESS(STUDENT_ID,CITY_NAME,PIN_CODE,STATE_NAME,STREET_NAME) values (?,?,?,?,?)

 

Inserting Primary key for collection inside entity class

 
To inset the primary key collection table I have modified the collection element in Entity class as shown below.
 

@ElementCollection
@JoinTable(name="ADDRESS",joinColumns=@JoinColumn(name="STUDENT_ID"))
@GenericGenerator(name="myGenerator", strategy="increment")
@CollectionId(columns = {@Column(name="ADDRESS_ID")}, 
                          generator="myGenerator",type=@Type(type="int"))
private Collection<Address> lisOfAddress = new ArrayList<Address>();

 

Here are the topics of interest for our code above:
  • Since the primary key is to be created at collection table, we use the @CollectionId instead of @Id annotation before the collection in Entity class.
  • With the @GenericGenerator annotation, we will to give some information to @CollectionId and tell how it should work. First off, we name this GenericGenerator whatever we like, for my example I just named it “myGenerator” but this is completely up to you. We also tell it what ID generation strategy to use, in this case I used “INCREMENT” strategy.
  • Oh, and let’s not forget to point our @GeneratedValue annotation to our newly minted customer @ CollectionId via the generator=”myGenerator” property.

 
Address.java and hibernate.cfg.xml and HibernateUtil.java is the same as previous post.
 

Run it – Eclipse console

 
On running the Hibernate test class with above changes, the collection table gets created as below.
 
Primary key in collection
 
Here ADDRESS_ID is the primary key which gets generated due to above code change.
 
Voila!
 
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Saving Collections in Hibernate

Posted by on Jun 6, 2015 in Hibernate, Hibernate Annotation | 1 comment

 
saving collections
 
In our last Hibernate article, we learned about Embedding value object into an entity class. In this article we’re going to focus on saving a Collection in Hibernate.
 
Consider a scenario where the student have lots of address. So in this case we need to create more no of embedded object in the student class, which is so tedious at certain point. In such case we can use Collection to solve this problem. This collection can be a list, set, map, collection, sorted set, sorted map. Hibernate provides the facility to persist the collections object via @ElementCollection annotation.
 

Entity Class

 

package entity;

import java.util.ArrayList;
import java.util.Collection;

import javax.persistence.Column;
import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "STUDENT")
public class Student {

	@Id
	@GeneratedValue
	@Column(name = "ID")
	private int id;

	@Column(name = "NAME")
	private String name;

	@Column(name = "DEPARTMENT")
	private String department;

	@Column(name = "COLLEGE")
	private String college;

	@ElementCollection
	private Collection<Address> lisOfAddress = new ArrayList<Address>();

        // Create Getters and Setters
}

 

@ElementCollection:

Defines a collection of instances of an embeddable class, this annotation must be specified if the collection is to be mapped by means of a collection table.
 

package entity;

import javax.persistence.Column;
import javax.persistence.Embeddable;

@Embeddable
public class Address {
	@Column(name = "STREET_NAME")
	private String street;
	@Column(name = "CITY_NAME")
	private String city;
	@Column(name = "STATE_NAME")
	private String state;
	@Column(name = "PIN_CODE")
	private String pincode;
        
        // Create Getters and Setters
}

 
hibernate.cfg.xml will be the same as in previous article.
 

HibernateTest class

 
Create the Main class to run the example.

package util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

import entity.Address;
import entity.Student;

public class HibernateUtil {

	public static void main(String[] args) {

		Configuration cf = new Configuration().configure("hibernate.cfg.xml");

		StandardServiceRegistryBuilder srb = 
                               new StandardServiceRegistryBuilder();
		srb.applySettings(cf.getProperties());
		ServiceRegistry sr = srb.build();
		SessionFactory sf = cf.buildSessionFactory(sr);

		Session session = sf.openSession();
		Transaction tx = session.beginTransaction();
		
		Address address1 = new Address(); 
		address1.setStreet("Race cource");
		address1.setCity("Coimbatore");
		address1.setState("Tamilnadu");
		address1.setPincode("642001");
		
		Address address2 = new Address();
		address2.setStreet("Besant nagar");
		address2.setCity("Chennai");
		address2.setState("Tamilnadu");
		address2.setPincode("600001");
		
		Student student = new Student(); 

		student.setName("Lahir Nisha");
		student.setDepartment("ECE");
		student.setCollege("SKCET");
		
		//adding addresses object to the list of address
		student.getLisOfAddress().add(address1);
		student.getLisOfAddress().add(address2);

                session.save(student); 
        
		tx.commit(); 
		session.close();
		sf.close();
	}
}

 

Rut it – Eclipse Console

 
Hibernate_collection
 
When you run the above program two tables are created in database, first table is for Student entity “STUDENT” and second table is for the embeddable object (Address) – “Student_lisOfAddress” (The default table name for this table gets generated based on – Entity class name_Name of the embeddable object in the entity class).
 
Here the ‘Student_ID’ column in ‘Student_lisOfAddress’ is the foreign key reference of Student tables ‘ID’. In next article we shall learn to override the default collection class table name and to add primary key to it.
 
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Value object & Entity object in Hibernate mapping

Posted by on Jun 6, 2015 in Hibernate, Hibernate Annotation | 0 comments

So far we have learnt how to write a model object and we learnt to annotate a model object so that hibernate create a table for us, then we learnt how to save, retrieve, update and delete the entity object in the database.
 
Hibrenet-
 
Still now we have created the entity class based on the assumption that each member variable inside the entity class will have a single column in database.
 
In Above table the type of fields of the class STUDENT CLASS is as below.

              ID            is INTEGER type
              Name          is VARCHAR type
              DEPARTMENT    is VARCHAR type
              ADDRESS       is VARCHAR type
              COLLEGE       is VARCHAR type

Now what if one of these member variable is an object instead of a simple data type. For example
 
Hibrenet-intro
 
Here STUDENT CLASS have a field Address object, this means in the database there are no meaning for Address object, as this Address object in turn have four other fields like.

1. Street
2. City
3. State
4. Pin code

Now the question is how can we save this address object into the database.
 

Value object

 
One way of saving the Address Object is to treat the member variable of address objects as the member variable of Student object itself.
 
Hibrenet-introduction
 
Here without having a Student object the use of Address object doesn’t make any sense. So the purpose of address object is just provide value to the Student object; And this is what differentiate an Entity object from a Value object.
 

So what the heck is Value object?

 
Entity object is the one which have meaning on its own, where a value object has no meaning on its own, the value object belongs to an entity instance and its persistent state is embedded in the table row of the owning entity.
In the above example the Student object represents an Entity object and Address object represents a Value object.
 

Long story short here:

 
Entity Object: Has its own database identity (Student table)
Value Object: Doesn’t not have its own database identity
 
Now let’s create an class for Address (Value object)
 

package entity;

import javax.persistence.Column;
import javax.persistence.Embeddable;

@Embeddable
public class Address {
	@Column(name = "STREET_NAME")
	private String street;
	@Column(name = "CITY_NAME")
	private String city;
	@Column(name = "STATE_NAME")
	private String state;
	@Column(name = "PIN_CODE")
	private String pincode;
        
        // Create getters and setters
}

 
Now in order to make this class of value type, and in order to tell hibernate not to create a separate table for address class, I have used @Embeddable annotation in the Address class, Also we need to use @Embedded annotation in the member variable of Address object in Student entity class as shown below.
 

package entity;

import javax.persistence.Column;
import javax.persistence.Embedded;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "STUDENT")
public class Student {

	@Id
	@GeneratedValue
	@Column(name = "ID")
	private int id;

	@Column(name = "NAME")
	private String name;

	@Column(name = "DEPARTMENT")
	private String department;

	@Column(name = "COLLEGE")
	private String college;

	// For value type object
	@Embedded
	private Address address;

       // Getters and Setters
}

 

Hibernate Configuration file

 
File: hibernate.cfg.xml

<hibernate-configuration>
<session-factory>
	<!-- Database connection settings -->
	<property name="hibernate.connection.driver_class">
                 oracle.jdbc.driver.OracleDriver
        </property>
	<property name="hibernate.connection.username">system</property>
	<property name="hibernate.connection.password">admin</property>
	<property name="hibernate.connection.url">
                jdbc:oracle:thin:@127.0.0.1:1521:XE
        </property>

	<!-- SQL dialect -->
	<property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>

	<!-- Echo all executed SQL to sysout -->
	<property name="show_sql">true</property>

	<!-- Drop and re-create the database schema on startup -->
	<property name="hibernate.hbm2ddl.auto">create</property>
	<!-- Map Entity Class -->
    <mapping class="entity.Student"></mapping>

</session-factory>

</hibernate-configuration>

 

HibernateTest class

 
Create the Main class to run the example.

package util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

import entity.Address;
import entity.Student;

public class HibernateUtil {

	public static void main(String[] args) {

		Configuration cf = new Configuration().configure("hibernate.cfg.xml");

		StandardServiceRegistryBuilder srb = 
                         new StandardServiceRegistryBuilder();
		srb.applySettings(cf.getProperties());
		ServiceRegistry sr = srb.build();
		SessionFactory sf = cf.buildSessionFactory(sr);

		Session session = sf.openSession();
		Transaction tx = session.beginTransaction();

		Student student = new Student(); 

		student.setName("Lahir Nisha");
		student.setDepartment("ECE");
		student.setCollege("SKCET");

		Address address1 = new Address();
		address1.setStreet("Race cource");
		address1.setCity("Coimbatore");
		address1.setState("Tamilnadu");
		address1.setPincode("642001");
		student.setAddress(address1);
                session.save(student);  

		tx.commit(); 
		session.close();
		sf.close();
	}
}

 

Run it – Eclipse Console

 
Vlue object
 

Database Output

 
Vlue object saving
 

@AttributeOverride annotation:

 
So far we have seen that an Entity Type Object Student has a Value Object(or Embeddable Object ) ADDRESS with corresponding fields name street, city, pin-code and state save to the database table STUDENT with value object’s column name (CITY_NAME, PIN_CODE, STATE_NAME, STREET_NAME).
 
Suppose in the above scenario if a Student have two addresses like Local Address and Permanent Address then how to manage the column names of these two value objects in the database table STUDENT.
 
In order to overcome this problem, we have to override the Attribute name of the Value objects. Hibernate has provided @AttributeOverride annotation for this purpose.
 
Example:-

Student.java

 

package entity;

import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.Embedded;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "STUDENT")
public class Student {

	@Id
	@GeneratedValue
	@Column(name = "ID")
	private int id;

	@Column(name = "NAME")
	private String name;

	@Column(name = "DEPARTMENT")
	private String department;

	@Column(name = "COLLEGE")
	private String college;

	@Column(name = "ADDRESS")
	@Embedded
	@AttributeOverrides({
	   @AttributeOverride(name = "street", column = @Column(name = "HOME_STREET_NAME")),
	   @AttributeOverride(name = "city", column = @Column(name = "HOME_CITY_NAME")),
	   @AttributeOverride(name = "state", column = @Column(name = "HOME_STATE_NAME")),
	   @AttributeOverride(name = "pincode", column = @Column(name = "HOME_PIN_CODE")) })
	private Address homeAddress;

	@Embedded
	private Address permanentAddress;
        // Create getters and setters 
}

 

HibernateTest class

 
Create the Main class to run the example.

package util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

import entity.Address;
import entity.Student;

public class HibernateUtil {

	public static void main(String[] args) {

		Configuration cf = new Configuration().configure("hibernate.cfg.xml");

		StandardServiceRegistryBuilder srb 
                             = new StandardServiceRegistryBuilder();
		srb.applySettings(cf.getProperties());
		ServiceRegistry sr = srb.build();
		SessionFactory sf = cf.buildSessionFactory(sr);

		Session session = sf.openSession();
		Transaction tx = session.beginTransaction();
		
		Address homeAddress = new Address(); 
		homeAddress.setStreet("Race cource");
		homeAddress.setCity("Coimbatore");
		homeAddress.setState("Tamilnadu");
		homeAddress.setPincode("642001");
		
		Address permanantAddress = new Address();
		permanantAddress.setStreet("Besant nagar");
		permanantAddress.setCity("Chennai");
		permanantAddress.setState("Tamilnadu");
		permanantAddress.setPincode("600001");
		
		Student student = new Student(); 

		student.setName("Lahir Nisha");
		student.setDepartment("ECE");
		student.setCollege("SKCET");
		student.setPermanentAddress(permanantAddress);
		student.setHomeAddress(homeAddress);

                session.save(student); 
        
		tx.commit(); 
		session.close();
		sf.close();
	}
}

 

Eclipse console after running this program


 
Hibernate: insert into STUDENT (COLLEGE, DEPARTMENT, HOME_CITY_NAME, HOME_PIN_CODE, HOME_STATE_NAME, HOME_STREET_NAME, NAME, CITY_NAME, PIN_CODE, STATE_NAME, STREET_NAME, ID) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
 
In our next article we shall learn about Saving Collections in Hibernate

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Composite Primary Keys In Hibernate

Posted by on Jun 2, 2015 in Hibernate, Hibernate Annotation | 0 comments

Composite Primary Keys In Hibernate
 
If the table has a primary key then in Entity class we configure that column using @Id annotation. Even when the table doesn’t need a primary key, we must configure one column as id (one primary key is must).
 
Now If the database table has more than one column as primary key then we call it as composite primary key, so if the table has multiple primary key columns , then in order to configure these primary key columns we need to create a new @Embeddable class containing the PK fields:
 

@Embeddable
public class RegistrationId implements Serializable{

	@Column(name = "STUDENT_ID")
	private int studentId;

	@Column(name = "DEPARTMENT")
	private String department;

        // Create getters and Setters 
}

 
And we should use it in the @Entity as a @EmbeddedId:
 

@Entity
@Table(name = "STUDENT")
public class StudentEntity {

	@EmbeddedId
	private RegistrationId regid;
        ...
        // Create Getters and Setters
}

 
To persist the entity:
 

   RegistrationId regId = new RegistrationId();
   regId.setStudentId(1);
   regId.setDepartment("ECE");

   StudentEntity student = new StudentEntity(); 
   student.setRegid(regId);
	
   session.save(student);

 
The following rules must apply for composite primary keys:

  • The primary key class must be public.
  • If property-based access is used, the properties of the primary key class must be public or protected.
  • The primary key class must be serializable. We shall explore the reason for implementing this interface in our upcoming tutorial.
  • A composite primary key must be represented and mapped as an embeddable class (EmbeddedId Annotation).

We shall explore the concept behind this composite primary keys in the next article.
 

Other Hibernate tutorial from our Blog

 

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