JSF页面组件化

页面组件化能带来很多优点,当多个页面引用同一个页面,这样,我们就只需要维护一个页面的代码,大大减轻开发人员的工作量。

假设网站的根目录为jsfApp,建立jsfApp/resources/echo目录,resources为默认的需要组件化的页面的根目录,echo为组件的前缀。

第一步

新增jsfApp/resources/echo/echoInputText.xhtml文件,内容如下:
<?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:ui="http://java.sun.com/jsf/facelets"
	xmlns:h="http://java.sun.com/jsf/html"
	xmlns:f="http://java.sun.com/jsf/core"
	xmlns:c="http://java.sun.com/jsp/jstl/core"
	xmlns:composite="http://java.sun.com/jsf/composite">
<h:head>
	<title>myjsf</title>
	<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
</h:head>
	<!--  INTERFACE  -->
	<composite:interface>
		<composite:attribute name="echo" />
	</composite:interface>
	
	<!--  IMPLEMENTATION  -->
	<composite:implementation>
		<div style="padding: 20px;">
			<span>请输入响应文字:</span>
			<h:inputText value="#{cc.attrs.echo.echoText}"></h:inputText>
		</div>
	</composite:implementation>
</html>
注意
xmlns:composite="http://java.sun.com/jsf/composite"
声明页面组件必须用到composite名字空间。

<composite:interface>
传入的参数。

<composite:implementation>
真正组件中的内容。

第二步

新增jsfApp/echo2.xhtml文件:
<?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:ui="http://java.sun.com/jsf/facelets"
	xmlns:h="http://java.sun.com/jsf/html"
	xmlns:f="http://java.sun.com/jsf/core"
	xmlns:c="http://java.sun.com/jsp/jstl/core"
	xmlns:echo="http://java.sun.com/jsf/composite/echo">
<h:head>
	<title>myjsf</title>
	<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
</h:head>
<body>
	<div id="header"
		style="padding: 100px 0 20px 100px; font-size: 22px; font-weight: bold; border-bottom: solid 1px red">
		这个应声器的作者是:#{inputEcho.encoder.author}。</div>
	<div>
		<h:form id="form" style="padding:20px  0  20px  100px">
			<echo:echoInputText echo="#{inputEcho}"></echo:echoInputText>
			<div style="padding-left: 50px">
				<h:commandButton id="post" style="padding:3px;100px;"
					value="提交响应" action="echo2" />
			</div>
		</h:form>
	</div>
	<h:panelGroup id="after">
		<div style="padding: 20px 0 0 100px">
			响应:
			<h:outputText id="echo" value="#{inputEcho.outText}" escape="false"></h:outputText>
		</div>
	</h:panelGroup>
</body>
</html>

使用echo前缀
xmlns:echo="http://java.sun.com/jsf/composite/echo"

使用echoInputText页面,并传入echo参数
<echo:echoInputText echo="#{inputEcho}"></echo:echoInputText>

Bean及工具类如下:
@ManagedBean(name="inputEcho") 
@SessionScoped
public class InputEcho implements Serializable {
	/**
	 * 
	 */
	private static final long serialVersionUID = 7599540489637124942L;
	
	private  String  echoText = "";
    private  EchoEncoder  encoder;
     
    public  InputEcho()  { 
        encoder  =  new  EchoEncoder(); 
    } 

    /** 
      *  @return  the  encoder 
      */ 
    public  EchoEncoder  getEncoder()  { 
        return  encoder; 
    } 

    /** 
      *  @return  the  echoText 
      */ 
    public  String  getEchoText()  { 
        return  echoText; 
    } 
     
    public  String  getOutText()  { 
        return  encoder.Encode(echoText); 
    } 

    /** 
      *  @param  echoText  the  echoText  to  set 
      */ 
    public  void  setEchoText(String  echoText)  { 
        this.echoText  =  echoText; 
    } 
     
    public  void  echo()  { 
    }
}

package com.zolcorp.myjsf.bean;

import java.io.Serializable;

public class EchoEncoder implements Serializable {

	/**
	 * 
	 */
	private static final long serialVersionUID = -5578888194809870790L;
	
	private String author = "pout";
    
    /** 
      * @return the author
      */ 
    public String getAuthor() { 
        return author; 
    } 

    public String Encode(String msg) {
    	if(msg == null)
    		return null;
        return msg.replaceAll("<", "<").replaceAll(">", ">").replaceAll("\n", "<br/>"); 
    }
}

页面组件化能大大减少维护的工作量。JSF2里配置也很简单。

原文地址:https://www.cnblogs.com/xinyuyuanm/p/3022863.html