jsp:useBean, jsp:setProperty and jsp:getProperty action tag

jsp:useBean action tag:

jsp:useBean action tag is used to instantiate a bean class. It first search for an existing instance using id and scope variables. If object is not found than it creates bean class object.

Commonly used attributes of jsp:useBean:

1. id: This attribute is used to uniquely identify the bean class within the specified block.

2. scope: This attribute represents the scope of the bean. Scope may page (default scope), request, session or application.

3. class: This attribute specifies the full package name of the bean.

Syntax: <jsp:useBean id=”beanName” class=”package.class”/> 

 jsp:setProperty action tag:

jsp:setProperty action tag is used to set the value of the specified bean property.

Commonly used attributes of jsp:setProperty:

1. name: This attribute refers to the bean class.property: This attribute specifies the bean property whose value is to be set.

2. value: This attribute specifies the value set to the bean property.

Syntax: <jsp:setPropertyname=”beanName” property=”propertyName” value=”propertyValue“/>   

jsp:getProperty action tag:

jsp:getProperty action tag is used to get the value of the specified bean property and insert it into output.

Commonly used attributes of jsp:getProperty:

1. name: This attribute refers to the bean class.

2. property: This attribute specifies the bean property whose value is to be retrieve.
Syntax: <jsp:getPropertyname=”beanName” property=”propertyName”/>

Example:

test.jsp

<html>
	<head>
	 <title>useBean,setProperty and getProperty action example</title>
	</head>
	<body>
		<h4>Enter student detail.</h4> 
		<form action="display.jsp" method="post"> 
		Name:  <input type="text" name="name"><br/><br/> 
		RollNo: <input type="text" name="rollNo"><br/><br/> 
		<input type="submit" value="Sign up"> 
		</form> 
	</body>
</html>

StudentBean.java

/**
 * This class is act as a java bean for a student.
 * @author javawithease
 */
public class StudentBean {
	//student properties
	private String name;
	private String rollNo;
 
	//no-argument constructor
	public StudentBean(){
 
	}
 
	public String getName() {
		return name;
	}
 
	public void setName(String name) {
		this.name = name;
	}
 
	public String getRollNo() {
		return rollNo;
	}
 
	public void setRollNo(String rollNo) {
		this.rollNo = rollNo;
	}	
}

display.jsp

<html>
	<head>
	 <title>useBean,setProperty and getProperty action example</title>
	</head>
	<body>
	 <h4>Student detail:</h4>
	 <jsp:useBean id="student"
                           class="com.javawithease.business.StudentBean"/>
         <jsp:setProperty name="student" property="*"/>
         Name:<jsp:getProperty name="student" property="name"/><br>
         RollNo:<jsp:getProperty name="student" property="rollNo"/><br>
	</body>
</html>

web.xml

<web-app>
 
  <welcome-file-list>
          <welcome-file>test.jsp</welcome-file>
  </welcome-file-list>	
 
</web-app>

Output:

jsp example 30 test
 
Enter Name and RollNo:
jsp example 30 value
 
Click on Sign up button:
jsp example 30 display
 
Download this example.
 
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Related Topics:

JSP action tags with example.
jsp:forward action tag with example.
jsp:include action tag with example.
jsp:param action tag with example.
jsp:useBean, jsp:setProperty and jsp:getProperty action tag.
Exception handling in JSP with example.
JSP Expression Language with example.