Struts 1將表單(<form>)資料轉為ActionFrom bean物進傳送到Action。
參考Eclipse 建立Struts 1專案進行設定，本範例依此進行修改。
本範例將index.jsp的表單form資料經Struts 1 ActionServlet轉為HelloForm bean傳送到接收的HelloAction類，然後forward至hello.jsp。
+-------------+ +-------------+ +-----------+
| index.jsp | | | | |
| +---------+ |------------------+-->| HelloAction |---forward--->| hello.jsp |
| |/hello.do| | +-----------+ | | | | |
| | <form> |-----| HelloForm |--+ +-------------+ +-----------+
| +---------+ | +-----------+
+-------------+
在strut-config.xml設定<form-bean>為com.abc.demo.action.form.HelloForm，並設定<action>的name為<form-bean>的名稱。當request經ActionServlet轉送到對應的<action>類com.abc.demo.action.HelloAction時會生成HelloForm的實例並將表單欄位的值塞入同名稱的屬性中。
strut-config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts-config PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 1.3//EN"
"http://struts.apache.org/dtds/struts-config_1_3.dtd">
<struts-config>
<form-beans>
<form-bean name="helloForm"
type="com.abc.demo.action.form.HelloForm" />
</form-beans>
<global-exceptions>
</global-exceptions>
<global-forwards>
</global-forwards>
<action-mappings>
<action path="/hello"
type="com.abc.demo.action.HelloAction"
name="helloForm">
<forward name="hello"
path="/WEB-INF/pages/hello.jsp" />
</action>
</action-mappings>
</struts-config>
com.abc.demo.action.form.HelloForm為一個簡單的POJO，要繼承Struts 1的ActionForm類。index.jsp 表單的輸入欄位的值會設定到HelloForm同名稱的屬性變數中，然後傳入HelloAction.execute()。
HelloForm
package com.abc.demo.action.form;
import org.apache.struts.action.ActionForm;
public class HelloForm extends ActionForm {
private static final long serialVersionUID = 1L;
private String name;
private String greeting;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGreeting() {
return greeting;
}
public void setGreeting(String greeting) {
this.greeting = greeting;
}
}
index.jsp的<form>的action為表單提交的request路徑，method為http request method。其中有兩個<input>輸入欄位，name屬性名稱對映到HelloForm的同名稱屬性。
index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Home</title>
</head>
<body>
<form name="helloForm" action="/struts1-demo/hello.do" method="post">
name:<input type="text" name="name"/><br>
greeting:<input type="text" name="greeting"/><br>
<input type="submit"/>
</form>
</body>
</html>
HelloAction.execute()的參數ActionForm實際是HelloForm，轉型後可從中取得屬性，然後放入request的attribute轉交給hello.jsp。
HelloAction
package com.abc.demo.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.abc.demo.action.form.HelloForm;
public class HelloAction extends Action {
@Override
public ActionForward execute(
ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response) throws Exception {
System.out.println("HelloAction.execute()...");
String name = ((HelloForm) form).getName();
String greeting = ((HelloForm) form).getGreeting();
System.out.println("name=" + name);
System.out.println("greeting=" + greeting);
request.setAttribute("name", name);
request.setAttribute("greeting", greeting);
return mapping.findForward("hello");
}
}
hello.jsp收到由HelloAction轉送來的request並透過JSP EL表達式取出。
hello.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Hello</title>
</head>
<body>
<h1>Hello ${name}, ${greeting}.</h1>
</body>
</html>
啟動專案後打開瀏覽器輸入http://localhost:8080/struts1-demo進入首頁index.jsp，並在表單填入內容如下。
點選提交按鈕結果如下。
範例專案目錄結構如下。
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