- JSF Tutorial
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- JSF - Architecture
- JSF - Life Cycle
- JSF - First Application
- JSF - Managed Beans
- JSF - Page Navigation
- JSF - Basic Tags
- JSF - Facelet Tags
- JSF - Convertor Tags
- JSF - Validator Tags
- JSF - DataTable
- JSF - Composite Components
- JSF - Ajax
- JSF - Event Handling
- JSF - JDBC Integration
- JSF - Spring Integration
- JSF - Expression Language
- JSF - Internationalization
- JSF Useful Resources
- JSF - Quick Guide
- JSF - Useful Resources
- JSF - Discussion
JSF - f:param
f:param tag provides the options to pass parameters to a component or pass request parameters.
JSF Tag
Pass parameter to a UI component
<h:outputFormat value = "Hello {0}!."> <f:param value = "World" /> </h:outputFormat>
Pass request parameter
<h:commandButton id = "submit" value = "Show Message" action = "#{userData.showResult}"> <f:param name = "username" value = "JSF 2.0 User" /> </h:commandButton>
Tag Attributes
S.No | Attribute & Description |
---|---|
1 | id Identifier for a component |
2 | binding Reference to the component that can be used in a backing bean |
3 | name An optional name for this parameter component |
4 | value The value stored in this component |
Example Application
Let us create a test JSF application to test the above tag.
Step | Description |
---|---|
1 | Create a project with a name helloworld under a package com.tutorialspoint.test as explained in the JSF - First Application chapter. |
2 | Modify home.xhtml as explained below. Keep rest of the files unchanged. |
3 | Create result.xhtml in the webapps directory as explained below. |
4 | Create UserData.java as a managed bean under package com.tutorialspoint.test as explained below. |
5 | Compile and run the application to make sure business logic is working as per the requirements. |
6 | Finally, build the application in the form of war file and deploy it in Apache Tomcat Webserver. |
7 | Launch your web application using appropriate URL as explained below in the last step. |
UserData.java
package com.tutorialspoint.test; import java.io.Serializable; import javax.faces.bean.ManagedBean; import javax.faces.bean.SessionScoped; @ManagedBean(name = "userData", eager = true) @SessionScoped public class UserData implements Serializable { private static final long serialVersionUID = 1L; public String data = "1"; public String getData() { return data; } public void setData(String data) { this.data = data; } public String showResult() { FacesContext fc = FacesContext.getCurrentInstance(); Map<String,String> params = fc.getExternalContext().getRequestParameterMap(); data = params.get("username"); return "result"; } }
home.xhtml
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns = "http://www.w3.org/1999/xhtml"> <head> <title>JSF Tutorial!</title> </head> <body> <h2>f:param example</h2> <hr /> <h:form> <h:outputFormat value = "Hello {0}!."> <f:param value = "World" /> </h:outputFormat> <br/> <h:commandButton id = "submit" value = "Show Message" action = "#{userData.showResult}"> <f:param name = "username" value = "JSF 2.0 User" /> </h:commandButton> </h:form> </body> </html>
result.xhtml
<?xml version = "1.0" encoding = "UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns = "http://www.w3.org/1999/xhtml" xmlns:f = "http://java.sun.com/jsf/core" xmlns:h = "http://java.sun.com/jsf/html" xmlns:ui = "http://java.sun.com/jsf/facelets"> <head> <title>JSF Tutorial!</title> </head> <h:body> <h2>Result</h2> <hr /> #{userData.data} </h:body> </html>
Once you are ready with all the changes done, let us compile and run the application as we did in JSF - First Application chapter. If everything is fine with your application, this will produce the following result.
Press Show Message button and you'll see the following result.
jsf_basic_tags.htm
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