javadoc pre标签 java web标签

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mob64ca1409970a 2024-08-19 13:51:57

文章标签 javadoc pre标签 html struts apache 文章分类 Java 后端开发

一.Struts标签简介

在Struts中为了方便用户的开发依然提供了很多成型的标签库。无论哪种标签库实际上

都是与四种属性（page、request、session、application）范围有关的操作，所以

JSTL和Struts标签库是完全可以混合使用的。但是是这种情况基本不可能出现，因为Struts

标签库已经具备了完全的功能，直接使用即可，一般在不实用Web框架时就会使用JSTL。

以下主要介绍三个核心标签库：html、bean、logic。

二.Bean标签

Bean标签库的主要作用是定义和访问JavaBean。

<bean:define>定义变量：

s2.jsp:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s2.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<bean:define id="info" scope="page">
	
		CaMnter
	
	</bean:define>
	
	<bean:define id="message" value="Save you from anything 07"></bean:define>
	
	<h2>内容1：${info }</h2>
	<h2>内容2：${pageScope.message }</h2>

</body>
</html>

javadoc pre标签 java web标签_apache

<bean:define>复制JavaBean对象：

s3.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s3.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<jsp:useBean id="copyBean" class="com.zyy.struts.vo.CopyBean" scope="page"></jsp:useBean>
	
	<jsp:setProperty property="message" name="copyBean" value="Save you from anything 07"/>
	
	<bean:define id="info" name="copyBean" property="message"></bean:define>
	
	<h2>复制后：${info }</h2>
	
	

</body>
</html>

<bean:define>中的id属性可以设置你给变量起的名或者你给复制过来的JavaBean起的名

name表示要复制的JavaBean的id。

CopyBean.java：

package com.zyy.struts.vo;

public class CopyBean {

	private String message;

	public String getMessage() {
		return message;
	}

	public void setMessage(String message) {
		this.message = message;
	}

}

javadoc pre标签 java web标签_struts_02

<bean:size>标签：

s4.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s4.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
	
		List me = new ArrayList() ;
	
		me.add("CaMnter") ;
		
		me.add("Save you from anything 07") ;
		
		pageContext.setAttribute("me", me) ;
	
	%>	

	<bean:size id="length" name="me" scope="page"/>
	
	<h2>长度：${length }</h2>

</body>
</html>

javadoc pre标签 java web标签_apache_03

<bean:cookie>标签：

s5.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s5.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<bean:cookie name="user" id="myCookie" value="CaMnter"/>
	
	<%
	
		//保存3000秒
		myCookie.setMaxAge(3000) ;
		
		response.addCookie(myCookie) ;
	
		
		Cookie cookies[] = request.getCookies() ;
		
		for(Cookie cookie : cookies){
			
	%>		
	
			<h3><%= cookie.getName()%>  -->  <%=cookie.getValue() %></h3>
	
	<%
	
	
		}
	
	%>		
		
		
		
	

</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_04

<bean:write>标签和<bean:include>标签：

s6.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s6.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<bean:define id="CaMnter">
	
		define_Save you from anything 07 
	
	</bean:define>

	<bean:write name="CaMnter" ></bean:write>

	<bean:include id="include" page="/jsp/content.html"/>
	
	${include }		
	
	

</body>
</html>

content.html：

<!DOCTYPE html>
<html>
<head>
<title>content.html</title>



<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">


</head>

<body>

	<h2>Save you from anything 07</h2>

</body>
</html>

javadoc pre标签 java web标签_html_05

<bean:resource>标签：

s7.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s7.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<bean:resource name="/jsp/content.xml" id="resource"/>
	
	<bean:write name="resource"/>

</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_06

<bean:message>标签与国际化：

s8.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s8.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<bean:message key="beanMessage.info" arg0="bean:" arg1="message"/>

</body>
</html>

资源文件Properties页面显示：

javadoc pre标签 java web标签_javadoc pre标签_07

资源文件Source页面显示：

javadoc pre标签 java web标签_javadoc pre标签_08

javadoc pre标签 java web标签_javadoc pre标签_09

三.Logic标签

logic标签的主要作用是进行各种逻辑处理。如：执行分支语句、迭代、比较等操作。

<logic:present>和<logic:notPresent>标签：

s9.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>s9.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
	
		request.setAttribute("CaMnter", "Save you from anything 07") ;
	
	%>
	
	<logic:present name="CaMnter" scope="request">
	
		<h2>我心中存在：${requestScope.CaMnter }</h2>
	
	</logic:present>
	
	<logic:notPresent name="me" scope="application">
	
		<h2>她心中的Application范围内也不存在我</h2>
	
	</logic:notPresent>
	

</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_10

<logic:empty>标签和<logic:notEmpty>标签：

sa.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>sa.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
	
		List<String> me = new ArrayList<String>() ;
	
		request.setAttribute("me", me) ;
	
	%>	
	
	<logic:empty name="me" scope="request">
	
		<h2>长度为0也被判为空</h2>
	
	</logic:empty>
	
	<logic:empty name="she" scope="request">
	
		<h2>不存在也被判为空</h2>
		
	</logic:empty>

</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_11

这里，提示一下：长度为0在<logic:empty>中也被判定为空。

关系运算标签：

sb.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>sb.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
	
		request.setAttribute("she", 7) ;
	
		request.setAttribute("me", "Save you from anything 07") ;
	
	%>	
	
	<logic:equal value="Save you from anything 07" name="me" scope="request">
	
		<h2>Save you from anything 07</h2>
	
	</logic:equal>
	
	<logic:notEqual value="forget her" name="me" scope="request">
	
		<h2>impossible</h2>
	
	</logic:notEqual>
	
	<logic:lessThan value="70" name="she" scope="request">
	
		<h2>小于70</h2>
	
	</logic:lessThan>
	
	<logic:greaterThan value="0" name="she" scope="request">
	
		<h2>大于0</h2>
	
	</logic:greaterThan>
	
	<logic:lessEqual value="7" name="she" scope="request">
	
		<h2>小于等于7</h2>
	
	</logic:lessEqual>
	
	<logic:greaterEqual value="7" name="she" scope="request">
	
		<h2>大于等于7</h2>
	
	</logic:greaterEqual>
	

</body>
</html>

javadoc pre标签 java web标签_apache_12

<logic:iterate>标签（logic标签库中最重要的）：

sc.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>sc.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
		String me_str[] = { "CaMnter", "Save you from anything 07" };

		request.setAttribute("me_str", me_str);
	%>

	<h3>输出数组：</h3>
	<ol>

		<logic:iterate id="me_part_str" name="me_str" scope="request">

			<li>${me_part_str }</li>

		</logic:iterate>

	</ol>

	<%
		List me_list = new ArrayList();

		me_list.add("07");

		me_list.add("Never remember me");

		request.setAttribute("me_list", me_list);
	%>

	<h3>输出List：</h3>
	<ol>

		<logic:iterate id="me_part_list" name="me_list" scope="request">

			<li>${me_part_list }</li>

		</logic:iterate>

	</ol>

	<%
		Map me_map = new HashMap();

		me_map.put("If time could go back",
				"I am willing to return to the past");

		request.setAttribute("me_map", me_map);
	%>

	<h3>输出Map：</h3>
	<ol>

		<logic:iterate id="me_part_map" name="me_map" scope="request">

			<li>${me_part_map.key } -- > ${me_part_map.value }</li>

		</logic:iterate>

	</ol>




</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_13

<logic:redirect>重定向标签：

修改struts-config.xml：

<struts-config>
	<form-beans>
	</form-beans>

	<global-exceptions>
	</global-exceptions>

	<global-forwards>
		<forward name="content" path="/jsp/content.html" />
	</global-forwards>

	<action-mappings>
	</action-mappings>

	<message-resources parameter="resource.MessageResources" />
</struts-config>

以上在<global-forwards>节点中添加了全局forward。

sd.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>sd.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<!-- 跳转到<global-forwards>中name="content"的forward配置的path路径 -->
	<logic:redirect forward="content"></logic:redirect>

</body>
</html>

content.xml：

<!DOCTYPE html>
<html>
<head>
<title>content.html</title>



<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">


</head>

<body>

	<h2>Save you from anything 07</h2>

</body>
</html>

javadoc pre标签 java web标签_javadoc pre标签_14

这里，可以看出由/jsp/sd.jsp变为/jsp/content.html。明显是客户端跳转。

四.Html标签

这个Html自带的标签很类似。

那么我们就来一张JSP就知道了，很多Struts Html库中标签的功能，其实和Html本身的标签真

是大同小异。

se.jsp：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean"
	prefix="bean"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html"
	prefix="html"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic"
	prefix="logic"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>


<title>se.jsp</title>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

</head>

<body>

	<%
		request.setCharacterEncoding("UTF-8");
	%>



	<html:form action="/jsp/simple.do" method="post">
	
		姓名：<html:text property="name"></html:text>
		<br>
		密码：<html:password property="password"></html:password>
		<br>
		性别：<html:radio property="sex" value="男">男</html:radio>
		<html:radio property="sex" value="女">女</html:radio>
		<br>	
		语言：<html:checkbox property="languages" value="Java">Java</html:checkbox>
		<html:checkbox property="languages" value="Android">Android</html:checkbox>
		<html:checkbox property="languages" value="C++">C++</html:checkbox>
		<html:checkbox property="languages" value="C#">C#</html:checkbox>
		<br>
		<br>
			  
		简介：<html:textarea property="note" cols="30" rows="3"></html:textarea>
		<br>

		<html:hidden property="id" value="7" />
		<html:submit value="提交"></html:submit>
		<html:reset value="重置"></html:reset>


	</html:form>

</body>
</html>

SimpleForm.java：

package com.zyy.struts.form;

import org.apache.struts.action.ActionForm;

public class SimpleForm extends ActionForm {

	private String name;

	private String password;

	private String sex;

	private String languages[];

	private String note;

	private int id;

	public String[] getLanguages() {
		return languages;
	}

	public void setLanguages(String[] languages) {
		this.languages = languages;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public String getSex() {
		return sex;
	}

	public void setSex(String sex) {
		this.sex = sex;
	}

	public String getNote() {
		return note;
	}

	public void setNote(String note) {
		this.note = note;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

}

SimpleAction.java：

package com.zyy.struts.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;

import com.zyy.struts.form.SimpleForm;

public class SimpleAction extends Action {

	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {

		request.setCharacterEncoding("UTF-8");

		SimpleForm simple = (SimpleForm) form;

		System.out.println("ID：" + simple.getId());
		System.out.println("name：" + simple.getName());
		System.out.println("password：" + simple.getPassword());
		System.out.println("sex：" + simple.getSex());
		System.out.print("languages：");
		for (String language : simple.getLanguages()) {

			System.out.print(language + "  ");

		}
		System.out.println("");
		System.out.println("note：" + simple.getNote());

		return null;
	}

}

修改struts-config.xml：

<struts-config>
	<form-beans>

		<form-bean name="simpleForm" type="com.zyy.struts.form.SimpleForm"></form-bean>
		
	</form-beans>

	<global-exceptions>
	</global-exceptions>

	<global-forwards>
		<forward name="content" path="/jsp/content.html" />
	</global-forwards>

	<action-mappings>

		<action path="/jsp/simple" attribute="simpleForm" input="/jsp/se.jsp"
			name="simpleForm" scope="request" type="com.zyy.struts.action.SimpleAction">
		</action>

	</action-mappings>

	<message-resources parameter="resource.MessageResources" />
</struts-config>

javadoc pre标签 java web标签_javadoc pre标签_15

但是，提交后一定有中文的乱码（sex：??）。

所以我们做一个过滤器SetCharacterEncodingFilter：

package com.zyy.struts.filters;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class SetCharacterEncodingFilter implements Filter {

	private String encoding;
	private FilterConfig filterConfig = null;

	public void destroy() {
		this.encoding = null;
		this.filterConfig = null;

	}

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		request.setCharacterEncoding(this.encoding);
		chain.doFilter(request, response);
	}

	public void init(FilterConfig filterConfig) throws ServletException {
		this.encoding = filterConfig.getInitParameter("encoding");
	}

}

配置struts-config.xml文件：

添加如下内容：

<filter>
  	<filter-name>Set Character Encoding</filter-name>
  	<filter-class>com.zyy.struts.filters.SetCharacterEncodingFilter</filter-class>
 	<init-param>
   	<param-name>encoding</param-name>
   	<param-value>UTF-8</param-value>
  	</init-param>
 </filter>

 <filter-mapping>
 	 <filter-name>Set Character Encoding</filter-name>
  	 <url-pattern>/*</url-pattern>
 </filter-mapping>

javadoc pre标签 java web标签_apache_16