第9章 Struts 2拦截器【首页】杜老师

1. 拦截器简介

2. 自定义拦截器

2.1 通过Interceptor接口实现拦截器

知识点：struts-2.3.16.3\src\xwork-core\src\main\java\com\opensymphony\xwork2\interceptor\Interceptor.java

(1) 创建项目01JavaWeb09, 01学号 java EE 5.0, 复制apps\struts2-blank-2.3.16.3\WEB-INF\lib下9个包到WEB-INF\lib

(2) 从apps\struts2-blank-2.3.16\WEB-INF\web.xml中复制粘贴有关filter部分到WebRoot\WEB-INF\web.xml中

(3) src创建cn.duzhaojiang.interceptor包，并创建[大门口的藏獒_01.java]

2.2 通过AbstractInterceptor类实现拦截器

知识点：struts-2.3.16.3\src\xwork-core\src\main\java\com\opensymphony\xwork2\interceptor\AbstractInterceptor.java

2.3 配置拦截器

知识点：在src\struts.xml的<package>节点之中1个<interceptors>

2.4 使用拦截器

(1) src创建cn.duzhaojiang.action包，并创建RegisterAction01.java

package cn.duzhaojiang.action;

import java.util.Calendar;
import java.util.Date;
import java.util.regex.Pattern;
import com.opensymphony.xwork2.ActionSupport;

public class RegisterAction01 extends ActionSupport {
	private String username;	// 用户名信息
	private String upassword;	// 密码信息
	private String repassword;	// 确认密码
	private String name;		// 姓名
	private int age;			// 年龄
	private Date birth;			// 出生日期
	private String email;		// email地址

public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getUpassword() {
		return upassword;
	}
	public void setUpassword(String upassword) {
		this.upassword = upassword;
	}
	public String getRepassword() {
		return repassword;
	}
	public void setRepassword(String repassword) {
		this.repassword = repassword;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}

public Date getBirth() {
		return birth;
	}
	public void setBirth(Date birth) {
		this.birth = birth;
	}
	public String getEmail() {
		return email;
	}
	public void setEmail(String email) {
		this.email = email;
	}

public void validate() {  // 校验器是否起作用？
		// 判断用户名是否输入,如果输入了再判断格式是否正确
		if (username == null || "".equals(username.trim())) {
			this.addFieldError("username", "用户名必须输入");
		} else if (!Pattern.matches("\\w{6,20}", username.trim())) {
			this.addFieldError("username", "用户名必须是字母和数字，长度为6到20之间");
		}
		// 判断密码是否输入,如果输入了再判断格式是否正确
		if (upassword == null || "".equals(upassword.trim())) {
			this.addFieldError("upassword", "密码必须输入");
		} else if (!Pattern.matches("\\w{6,20}", upassword.trim())) {
			this.addFieldError("upassword", "密码必须是字母和数字，长度为6到20之间");
		}
		// 判断确认密码是否输入,如果输入了再判断格式是否正确
		if (repassword == null || "".equals(repassword.trim())) {
			this.addFieldError("repassword", "确认密码必须输入");
		} else if (!Pattern.matches("\\w{6,20}", repassword.trim())) {
			this.addFieldError("repassword", "确认密码必须是字母和数字，长度为6到20之间");
		}
		// 判断确认密码和密码是否相同
		if (upassword != null && repassword != null
				&& !repassword.equals(upassword)) {
			this.addFieldError("repassword", "确认密码和密码必须相同");
		}
		if (name != null && (name.length() < 2 || name.length() > 5)) {
			this.addFieldError("name", "姓名长度必须在2到5之间");
		}
		// 判断年龄是否合法
		if (age < 0 || age > 100) {
			this.addFieldError("age", "请输入有效的年龄");
		}
		// 判断出生日期是否合法
		Calendar start = Calendar.getInstance();
		Calendar end = Calendar.getInstance();
		start.set(1900, 1, 1);
		end.set(2010, 1, 1);
		if (birth != null
				&& (birth.after(end.getTime()) || birth.before(start.getTime()))) {
			this.addFieldError("birth", "请输入有效的出生日期");
		}
		// 判断邮箱地址是否合法
		if (email != null
				&& !"".equals(email)
				&& email != ""
				&& !Pattern
						.matches(
								"[a-zA-Z][a-zA-Z0-9._-]*@([a-zA-Z0-9-_]+\\.)+(com|gov|net|com\\.cn|edu\\.cn)",
								email)) {
			this.addFieldError("email", "请输入正确的邮箱地址");
		}
	}

public String execute() throws Exception {// 执行方法
		return "success";
	}
}

(2) 创建入口[用户注册页面]文件WebRoot\Register01.jsp

<%@page language="java" pageEncoding="gbk"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
	<head>
		<title>用户注册页面</title>
</head>
<body>
	<form action="register.action" method="post">
		<table>
			<tr>
				<td>用户名：</td>
				<td><input type="text" name="username" value="${param.username }"></td>
				<td><s:fielderror><s:param>username</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td>密码：</td>
				<td><input type="password" name="upassword" value="${param.upassword }"></td>
				<td><s:fielderror><s:param>upassword</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td>确认密码：</td>
				<td><input type="password" name="repassword" value="${param.repassword}"></td>
				<td ><s:fielderror><s:param>repassword</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td>姓名：</td>
				<td><input type="text" name="name" value="${param.name}"></td>
				<td><s:fielderror><s:param>name</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td>年龄：</td>
				<td><input type="text" name="age" value="${param.age}"></td>
				<td><s:fielderror><s:param>age</s:param></s:fielderror></td>
			</tr>	
			<tr>
				<td>出生日期：</td>
				<td><input type="text" name="birth" value="${param.birth}"></td>
				<td><s:fielderror><s:param>birth</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td>邮箱地址：</td>
				<td><input type="text" name="email" value="${param.email }"></td>
				<td><s:fielderror><s:param>email</s:param></s:fielderror></td>
			</tr>
			<tr>
				<td><input type="submit" value="提交"></td>
				<td><input type="reset" value="重置"></td>
			</tr>
		</table>
	</form>
</body>
</html>

创建[用户信息输出]页面文件WebRoot\ShowUserInfo01.jsp

创建[操作失败]页面文件WebRoot\OperError01.jsp

(3) 创建首页文件WebRoot\index.jsp

(4) 配置src\struts.xml，部署执行首页index.jsp测试，观察tomcat控制台输出。

2.5 使用默认拦截器

在src\struts.xml中，<interceptor-ref name="藏獒"></interceptor-ref>添加<interceptor-ref name="defaultStack"></interceptor-ref>

3. 深入拦截器

3.1 为拦截器传入参数

(1) 继承AbstractInterceptor实现拦截器

在cn.duzhaojiang.interceptor包，并创建[楼门口的大黄狗_01.java](继承AbstractInterceptor实现)

(2) 配置拦截器时配置参数

配置src\struts.xml，部署执行首页index.jsp测试，观察tomcat控制台输出。

(3) 引用拦截器时配置参数

配置src\struts.xml，部署执行首页index.jsp测试，观察tomcat控制台输出。

3.2 配置拦截器栈

(1) 配置拦截器栈时配置参数

配置src\struts.xml，部署执行首页index.jsp测试，观察tomcat控制台输出。

<package name="struts2" extends="struts-default">
	 	<interceptors>
			<interceptor name="藏獒" class="cn.duzhaojiang.interceptor.大门口的藏獒_01"></interceptor>
			<interceptor name="黄狗" class="cn.duzhaojiang.interceptor.楼门口的大黄狗_01">
				<param name="interceptorName">可爱的大黄狗</param>
			</interceptor>
			<interceptor-stack name="我的狗儿们">
				<interceptor-ref name="藏獒" />
				<interceptor-ref name="黄狗" />
			</interceptor-stack>
		</interceptors>
		
		<action name="register" class="cn.duzhaojiang.action.RegisterAction01">
			<result name="success">/ShowUserInfo01.jsp</result>
			<result name="input">/Register01.jsp</result>
			<result name="error">/OperError01.jsp</result>
			<interceptor-ref name="我的狗儿们" />
			<interceptor-ref name="defaultStack"/>
		</action> 
	</package>	
</struts>

(2) 引用拦截器栈时配置参数

配置src\struts.xml，重新部署执行首页index.jsp测试，观察tomcat控制台输出。

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
	"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
	"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
	<constant name="struts.i18n.encoding" value="gbk" />
	<package name="struts2" extends="struts-default">
	 	<interceptors>
			<interceptor name="藏獒" class="cn.duzhaojiang.interceptor.大门口的藏獒_01" />
			<interceptor name="黄狗" class="cn.duzhaojiang.interceptor.楼门口的大黄狗_01"/>
			<interceptor-stack name="我的狗儿们">
				<interceptor-ref name="藏獒" />
				<interceptor-ref name="黄狗" >
					<param name="interceptorName">讨厌的大黄狗</param>
				</interceptor-ref>
				<interceptor-ref name="defaultStack"/>
			</interceptor-stack>
	 	</interceptors>
		<action name="register" class="cn.duzhaojiang.action.RegisterAction01">
			<result name="success">/ShowUserInfo01.jsp</result>
			<result name="input">/Register01.jsp</result>
			<result name="error">/OperError01.jsp</result>
			<interceptor-ref name="我的狗儿们" />
		</action> 
	</package>	
</struts>

3.3 覆盖拦截栈中指定拦截器的参数

配置src\struts.xml，重新部署执行首页index.jsp测试，观察tomcat控制台输出。

3.4 拦截器的执行顺序

知识点：栈(先进后出)、见图

4. Struts 2内建拦截器

知识点：struts-2.3.16.3\src\core\src\main\resources\struts-default.xml

<?xml version="1.0" encoding="UTF-8" ?>

<!--
    When declaring beans in this file you must either use name="struts" or don't name the bean at all.

The name="struts" must be used when alias was defined in {@link org.apache.struts2.config.DefaultBeanSelectionProvider} -
    it is then the default bean's name and {@link org.apache.struts2.config.DefaultBeanSelectionProvider} links name "struts"
    with "default" (aliasing it)

If name won't be defined then the "default" value will be used {@link com.opensymphony.xwork2.inject.Container#DEFAULT_NAME}
    and {@link com.opensymphony.xwork2.inject.Inject}
-->
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<bean type="ognl.PropertyAccessor" name="java.util.ArrayList" class="com.opensymphony.xwork2.ognl.accessor.XWorkListPropertyAccessor" />
    <bean type="ognl.PropertyAccessor" name="java.util.HashSet" class="com.opensymphony.xwork2.ognl.accessor.XWorkCollectionPropertyAccessor" />
    <bean type="ognl.PropertyAccessor" name="java.util.HashMap" class="com.opensymphony.xwork2.ognl.accessor.XWorkMapPropertyAccessor" />

<interceptor-stack name="basicStack">
                <interceptor-ref name="exception"/>
                <interceptor-ref name="servletConfig"/>
                <interceptor-ref name="prepare"/>
                <interceptor-ref name="checkbox"/>
                <interceptor-ref name="multiselect"/>
                <interceptor-ref name="actionMappingParams"/>
                <interceptor-ref name="params">
                    <param name="excludeParams">^action:.*,^method:.*</param>
                </interceptor-ref>
                <interceptor-ref name="conversionError"/>
                <interceptor-ref name="deprecation"/>
            </interceptor-stack>

<interceptor-stack name="validationWorkflowStack">
                <interceptor-ref name="basicStack"/>
                <interceptor-ref name="validation"/>
                <interceptor-ref name="workflow"/>
            </interceptor-stack>

<interceptor-stack name="fileUploadStack">
                <interceptor-ref name="fileUpload"/>
                <interceptor-ref name="basicStack"/>
            </interceptor-stack>

<interceptor-stack name="modelDrivenStack">
                <interceptor-ref name="modelDriven"/>
                <interceptor-ref name="basicStack"/>
            </interceptor-stack>

<interceptor-stack name="chainStack">
                <interceptor-ref name="chain"/>
                <interceptor-ref name="basicStack"/>
            </interceptor-stack>

<interceptor-stack name="i18nStack">
                <interceptor-ref name="i18n"/>
                <interceptor-ref name="basicStack"/>
            </interceptor-stack>

<!-- An example of the paramsPrepareParams trick. This stack
                 is exactly the same as the defaultStack, except that it
                 includes one extra interceptor before the prepare interceptor:
                 the params interceptor.

This is useful for when you wish to apply parameters directly
                 to an object that you wish to load externally (such as a DAO
                 or database or service layer), but can't load that object
                 until at least the ID parameter has been loaded. By loading
                 the parameters twice, you can retrieve the object in the
                 prepare() method, allowing the second params interceptor to
                 apply the values on the object. -->
            <interceptor-stack name="paramsPrepareParamsStack">
                <interceptor-ref name="exception"/>
                <interceptor-ref name="alias"/>
                <interceptor-ref name="i18n"/>
                <interceptor-ref name="checkbox"/>
                <interceptor-ref name="multiselect"/>
                <interceptor-ref name="params">
                    <param name="excludeParams">^action:.*,^method:.*</param>
                </interceptor-ref>
                <interceptor-ref name="servletConfig"/>
                <interceptor-ref name="prepare"/>
                <interceptor-ref name="chain"/>
                <interceptor-ref name="modelDriven"/>
                <interceptor-ref name="fileUpload"/>
                <interceptor-ref name="staticParams"/>
                <interceptor-ref name="actionMappingParams"/>
                <interceptor-ref name="params">
                    <param name="excludeParams">^action:.*,^method:.*</param>
                </interceptor-ref>
                <interceptor-ref name="conversionError"/>
                <interceptor-ref name="validation">
                    <param name="excludeMethods">input,back,cancel,browse</param>
                </interceptor-ref>
                <interceptor-ref name="workflow">
                    <param name="excludeMethods">input,back,cancel,browse</param>
                </interceptor-ref>
            </interceptor-stack>

<!-- A complete stack with all the common interceptors in place.
                 Generally, this stack should be the one you use, though it
                 may do more than you need. Also, the ordering can be
                 switched around (ex: if you wish to have your servlet-related
                 objects applied before prepare() is called, you'd need to move
                 servletConfig interceptor up.

This stack also excludes from the normal validation and workflow
                 the method names input, back, and cancel. These typically are
                 associated with requests that should not be validated.
                 -->
            <interceptor-stack name="defaultStack">
                <interceptor-ref name="exception"/>
                <interceptor-ref name="alias"/>
                <interceptor-ref name="servletConfig"/>
                <interceptor-ref name="i18n"/>
                <interceptor-ref name="prepare"/>
                <interceptor-ref name="chain"/>
                <interceptor-ref name="scopedModelDriven"/>
                <interceptor-ref name="modelDriven"/>
                <interceptor-ref name="fileUpload"/>
                <interceptor-ref name="checkbox"/>
                <interceptor-ref name="multiselect"/>
                <interceptor-ref name="staticParams"/>
                <interceptor-ref name="actionMappingParams"/>
                <interceptor-ref name="params">
                    <param name="excludeParams">^action:.*,^method:.*</param>
                </interceptor-ref>
                <interceptor-ref name="conversionError"/>
                <interceptor-ref name="validation">
                    <param name="excludeMethods">input,back,cancel,browse</param>
                </interceptor-ref>
                <interceptor-ref name="workflow">
                    <param name="excludeMethods">input,back,cancel,browse</param>
                </interceptor-ref>
                <interceptor-ref name="debugging"/>
                <interceptor-ref name="deprecation"/>
            </interceptor-stack>

<interceptor-stack name="completeStack">
                <interceptor-ref name="defaultStack"/>
            </interceptor-stack>

<interceptor-stack name="executeAndWaitStack">
                <interceptor-ref name="execAndWait">
                    <param name="excludeMethods">input,back,cancel</param>
                </interceptor-ref>
                <interceptor-ref name="defaultStack"/>
                <interceptor-ref name="execAndWait">
                    <param name="excludeMethods">input,back,cancel</param>
                </interceptor-ref>
            </interceptor-stack>

</interceptors>

<default-interceptor-ref name="defaultStack"/>

<default-class-ref class="com.opensymphony.xwork2.ActionSupport" />
    </package>

</struts>

5. 通过拦截器实现用户权限控制(实训9.1)

(1) 在cn.duzhaojiang.interceptor包，并创建使用AbstractInterceptor类实现拦截器[UserPopedom01.java]

(2) 配置src\struts.xml，重新部署执行首页index.jsp测试

6. 上机题

6.1 上机题1-6

(1) 在cn.duzhaojiang.interceptor包，并创建使用Interceptor接口实现拦截器[MyInter1_01.java](上机题1)

(2) 在cn.duzhaojiang.interceptor包，并创建使用AbstractInterceptor类实现拦截器[MyInter2_01.java](上机题2)

(3) 配置src\struts.xml文件，重部署执行index.jsp测试(上机题3)：拦截器2起作用，defaultStack不起作用，观察tomcat控制台输出。

(4) 配置src\struts.xml文件，重部署执行index.jsp测试(上机题4): defaultStack起作用(action没有配置interceptor-ref)，观察tomcat控制台输出。

(5) 配置src\struts.xml文件，重部署执行index.jsp测试(上机题5)：拦截器1、2起作用，defaultStack不起作用，观察tomcat控制台输出。

<package name="struts2" extends="struts-default">
		<interceptors>
			<interceptor name="我的拦截器1" class="cn.duzhaojiang.interceptor.MyInter1_01"></interceptor>
			<interceptor name="我的拦截器2" class="cn.duzhaojiang.interceptor.MyInter2_01"></interceptor>
			<interceptor-stack name="myStack">
				<interceptor-ref name="我的拦截器1"></interceptor-ref>
				<interceptor-ref name="我的拦截器2"></interceptor-ref>
			</interceptor-stack>
		</interceptors>
		<action name="register" class="cn.duzhaojiang.action.RegisterAction01">
			<result name="success">/ShowUserInfo01.jsp</result>
			<result name="input">/Register01.jsp</result>
			<result name="error">/OperError01.jsp</result>
			<interceptor-ref name="myStack">
				<param name="我的拦截器2.personName">李艳</param>
			</interceptor-ref>
		</action>
	</package>	
</struts>

(6) 配置src\struts.xml文件，重部署执行index.jsp测试(上机题6)：拦截器1、2起作用(参数没传入)，defaultStack不起作用，观察tomcat控制台输出。

<package name="struts2" extends="struts-default">
		<interceptors>
			<interceptor name="我的拦截器1" class="cn.duzhaojiang.interceptor.MyInter1_01"></interceptor>
			<interceptor name="我的拦截器2" class="cn.duzhaojiang.interceptor.MyInter2_01"></interceptor>
			<interceptor-stack name="myStack">
				<interceptor-ref name="我的拦截器1"></interceptor-ref>
				<interceptor-ref name="我的拦截器2"></interceptor-ref>
			</interceptor-stack>
		</interceptors>
		<default-interceptor-ref name="myStack"></default-interceptor-ref>
		<action name="register" class="cn.duzhaojiang.action.RegisterAction01">
			<result name="success">/ShowUserInfo01.jsp</result>
			<result name="input">/Register01.jsp</result>
			<result name="error">/OperError01.jsp</result>
		</action>
	</package>	
</struts>

6.2 上机题7 (用户登录拦截器)

在cn.duzhaojiang.interceptor包，创建LoginInterceptor01.java

6.3 上机题8 (参数拦截器：控制台显示jsp中的参数uname)

(1) 在cn.duzhaojiang.action包，创建ParamAction01.java

(2) 在cn.duzhaojiang.interceptor包，创建[参数拦截器]ParamInterceptor01.java

(3) 创建[参数输入]页面文件WebRoot\ParamInput01.jsp

(4) 创建[参数显示]页面WebRoot\ShowParam01.jsp

(5) 配置src\struts.xml文件，重部署执行index.jsp测试，观察tomcat控制台输出。

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