The <html:optionsCollection> tag renders a set of HTML <option> elements, representing possible choices for a <select> element. This tag can be used multiple times within a single <html:select> element, either in conjunction with or instead of one or more <html:option> or <html:options> elements.
<%@taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
First create a new Dynamic Web Project and configure it as Maven Project. For Reference, Click Here
Add the following dependencies in pom.xml
<dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.8.2</version> <scope>test</scope> </dependency> <dependency> <groupId>org.apache.struts</groupId> <artifactId>struts-core</artifactId> <version>1.3.10</version> </dependency> <dependency> <groupId>org.apache.struts</groupId> <artifactId>struts-taglib</artifactId> <version>1.3.10</version> </dependency> </dependencies>
1. Create JSP
Now we will create a HTML dropdown using Struts’s HTML tag
Write the following code in dropdown.jsp
<%@taglib uri="http://struts.apache.org/tags-html" prefix="html"%> <html> <head> <title>Struts <Html:optionsCollection> OptionsCollection Tag</title> </head> <body> <html:form action="/dropdown"> Fruit : <html:select property="fruit" value="Select"> <html:option value="Select">Select</html:option> <html:optionsCollection name="StrutsDropDownForm" property="fruitList" label="label" value="value" /> </html:select> <html:submit>Submit</html:submit> </html:form> </body> </html>
Now create another JSP output.jsp that displays dropdown value. Write the following code in output.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%> <%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean"%> <!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=UTF-8"> <title>Output Page</title> </head> <body> Selected Fruit - <bean:write name="StrutsDropDownForm" property="fruit" /> </body> </html>
2. Action Form
Create a Action Form class and name it StrutsDropDownForm.java that contains the following code.
package com.kruders.form;
import java.util.ArrayList;
import org.apache.struts.action.ActionForm;
import org.apache.struts.util.LabelValueBean;
public class StrutsDropDownForm extends ActionForm{
private static final long serialVersionUID = 1L;
private String fruit;
ArrayList fruitList = new ArrayList();
public String getFruit() {
return fruit;
}
public void setFruit(String fruit) {
this.fruit = fruit;
}
public ArrayList getFruitList() {
fruitList.add(new LabelValueBean("Apple", "Apple"));
fruitList.add(new LabelValueBean("Mango", "Mango"));
return fruitList;
}
public void setFruitList(ArrayList fruitList) {
this.fruitList = fruitList;
}
}
If we have only label and value then we can use the LabelValueBean class to add the label and value to the ArrayList.
fruitList.add(new LabelValueBean("Apple", "Apple"));
fruitList.add(new LabelValueBean("Mango", "Mango"));
You can display fruit list in JSP Page like this
<html:optionsCollection name="StrutsDropDownForm" property="fruitList" label="label" value="value" />
We can also create a separate class for Fruit and add it to ArrayList as shown below.
Fruit Class can be like this
public class Fruit {
private String fruitId;
private String fruitName;
public String getFruitId() {
return fruitId;
}
public void setFruitId(String fruitId) {
this.fruitId = fruitId;
}
public String getFruitName() {
return fruitName;
}
public void setFruitName(String fruitName) {
this.fruitName = fruitName;
}
}
You can add Fruit object inside ArrayList like this
fruitList.add(new Fruit("1", "Apple"));
fruitList.add(new Fruit("2", "Mango"));
You can display fruit list in JSP Page like this
<html:optionsCollection name="StrutsDropDownForm" property="fruitList" label="fruitName" value="fruitId" />
3. Action Class (Controller)
Let us create an Action class StrutsDropDownAction.java that will handles and forward the request.
package com.kruders.action;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
public class StrutsDropDownAction extends Action{
public ActionForward execute(ActionMapping mapping,ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
return mapping.findForward("success");
}
}
4. Struts Config
Write the following code in struts-config.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.3//EN" "http://jakarta.apache.org/struts/dtds/struts-config_1_3.dtd"> <struts-config> <form-beans> <form-bean name="StrutsDropDownForm" type="com.kruders.form.StrutsDropDownForm"/> </form-beans> <global-forwards> <forward name="dropdown" path="/dropdown.do"/> </global-forwards> <action-mappings> <action input="/dropdown.jsp" name="StrutsDropDownForm" path="/dropdown" validate="true" scope="request" type="com.kruders.action.StrutsDropDownAction"> <forward name="success" path="/output.jsp" /> </action> </action-mappings> </struts-config>
5. Deployment Descriptor
Now configure the deployment descriptor. Here, we have asked the container to give our ActionServlet any request that matches the pattern *.do
Add the following configuration information in the web.xml file
<welcome-file-list> <welcome-file>dropdown.jsp</welcome-file> </welcome-file-list> <servlet> <servlet-class> org.apache.struts.action.ActionServlet </servlet-class> <init-param> <param-name>config</param-name> <param-value>/WEB-INF/struts-config.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>action</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping>
6. Run Project
Now when you run the project, following screen will be displayed as shown in Figure 30.1
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Figure 30.1
Now when you select any value in dropdown and click submit button, following screen will be displayed as shown in Figure 30.2
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Figure 30.2
The folder structure of the example is shown below in Figure 30.3
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Figure 30.3