Struts2訪問Servlet
- 2019 年 10 月 7 日
- 筆記
知識點：
servlet是單例的，Action是多例的，一次請求，創建一個Action的實例
結果頁面分為全局和局部兩類（局部優先順序更高）
result標籤： name : 默認succes type ：頁面跳轉類型 dispatcher 默認值，請求轉發（action轉發jsp） redirect 重定向（action重定向jsp） chain 轉發（action轉發action） redirectAction 重定向（action重定向action） stream struts2中提供文件下載的功能
程式碼如下
struts.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN" "http://struts.apache.org/dtds/struts-2.5.dtd"> <struts> <package name="demo1" extends="struts-default"> <!--全局結果頁面--> <global-results> <result name="success">servlet1/demo2.jsp</result> </global-results> <action name="requestDemo1" class="com.jinke.servlet1.RequestDemo1"/> <action name="requestDemo2" class="com.jinke.servlet1.RequestDemo2"/> <action name="requestDemo3" class="com.jinke.servlet1.RequestDemo3"/> <!--局部結果頁面--> <action name="requestDemo1" class="com.jinke.servlet1.RequestDemo1"> <result name="success">servlet1/demo2.jsp</result> </action> <action name="requestDemo2" class="com.jinke.servlet1.RequestDemo2"> <result name="success">servlet1/demo2.jsp</result> </action> <action name="requestDemo3" class="com.jinke.servlet1.RequestDemo3"> <result name="success">servlet1/demo2.jsp</result> </action> </package> </struts>
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <welcome-file-list> <welcome-file>servlet1/demo1.jsp</welcome-file> </welcome-file-list> <filter> <filter-name>struts2</filter-name> <filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>
demo1.jsp
<%-- Created by IntelliJ IDEA. User: wanglei Date: 2019/6/18 Time: 11:03 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>Title</title> </head> <body> <h1>Struts2訪問Servlet的API</h1> <h3>方式一：完成解耦合的方式</h3> <form action="${pageContext.request.contextPath}/requestDemo1.action" method="post"> 姓名：<input type="text" name="name"><br/> 密碼：<input type="password" name="password"><br/> <input type="submit" value="提交"></form> <h3>方式二：完成原生的方式訪問</h3> <form action="${pageContext.request.contextPath}/requestDemo2.action" method="post"> 姓名：<input type="text" name="name"><br/> 密碼：<input type="password" name="password"><br/> <input type="submit" value="提交"></form> <h3>方式三：介面注入的方式訪問</h3> <form action="${pageContext.request.contextPath}/requestDemo3.action" method="post"> 姓名：<input type="text" name="name"><br/> 密碼：<input type="password" name="password"><br/> <input type="submit" value="提交"></form> </body> </html>
demo2.jsp
<%-- Created by IntelliJ IDEA. User: wanglei Date: 2019/6/18 Time: 11:24 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>Title</title> </head> <body> <h1>顯示數據</h1> ${reqName}<br/> ${sessName}<br/> ${appName}<br/> </body> </html>
action層
import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ActionSupport; import org.apache.struts2.dispatcher.HttpParameters; /** * 訪問Servlet的API方式一：完全解耦合的方式 */ public class RequestDemo1 extends ActionSupport { @Override public String execute() throws Exception { //接收參數 //利用struts2中的對象ActionContext對象 ActionContext context = ActionContext.getContext(); //調用ActionContext中方法 HttpParameters map = context.getParameters(); // System.out.println(map); //二.向域對象中存入數據 context.put("reqName", map);//相當於request.setAttribute() context.getSession().put("sessName", map);//相當於session.setAttribute() context.getApplication().put("appName", map);//相當於application.setAttribute() return SUCCESS; } }
import com.opensymphony.xwork2.ActionSupport; import org.apache.struts2.ServletActionContext; import javax.servlet.http.HttpServletRequest; import java.util.Map; /** * 訪問Servlet的API方式二：採用原生的方式 */ public class RequestDemo2 extends ActionSupport { @Override public String execute() throws Exception { //一、接收數據 //直接獲得request對象，通過ServletActionSupport HttpServletRequest request = ServletActionContext.getRequest(); Map<String, String[]> map = request.getParameterMap(); System.out.println(map.toString()); //二、向域對象中保存數據 //向request中保存數據 request.setAttribute("reqName", map.toString()); //向session中保存數據 request.getSession().setAttribute("sessName", map.toString()); //向application中保存數據 ServletActionContext.getServletContext().setAttribute("appName", map.toString()); return SUCCESS; } }
import com.opensymphony.xwork2.ActionSupport; import org.apache.struts2.interceptor.ServletRequestAware; import org.apache.struts2.util.ServletContextAware; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import java.util.Arrays; import java.util.Map; /** * 訪問Servlet的API方式三：介面注入的方式 */ public class RequestDemo3 extends ActionSupport implements ServletRequestAware, ServletContextAware { private HttpServletRequest request; private ServletContext context; @Override public String execute() throws Exception { //一、接收參數 //通過介面注入的方式獲得request對象 Map<String, String[]> map = request.getParameterMap(); for (String key : map.keySet()) { String[] value = map.get(key); System.out.println(key + " " + Arrays.toString(value)); } //二、向域對象中保存數據 //向request域中保存數據 request.setAttribute("reqName", map.toString()); //向session中保存數據 request.getSession().setAttribute("sessName", map.toString()); //向Application中保存數據 context.setAttribute("appName", map.toString()); return super.execute(); } @Override public void setServletRequest(HttpServletRequest httpServletRequest) { this.request = httpServletRequest; } @Override public void setServletContext(ServletContext servletContext) { this.context = servletContext; } }
結果
