我在test.jsp后面单击submit按钮,并尝试在transactionBean中设置值并在HelloWorld.jsp上显示,但是getTransactionBean()返回null。你能告诉我出什么事了吗?
test.jsp
<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<title>Struts 2 - Login Application</title>
</head>
<body>
<h2>Struts 2 - Login Application</h2>
<s:actionerror />
<s:form action="displayActionlogmetoo.action" method="post">
<s:submit method="logmetoo" key="login" align="center" />
</s:form>
</body>
</html> HelloWorld.jsp
<%@ page contentType="text/html; charset=UTF-8" %>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<title>Hello World</title>
</head>
<body>
username <s:property value="transactionBean.username"/>
password <s:property value="transactionBean.password"/>
</body>
</html>我的Struts.xml是:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="default" namespace="/" extends="struts-default">
<action name="displayActionlogmetoo"
class="com.tutorialspoint.struts2.DisplayLoginAction"
method="logmetoo">
<result name="success">HelloWorld.jsp</result>
</action>
</package>
</struts>我的行动是:
public class DisplayLoginAction extends ActionSupport {
private TransactionBean transactionBean;
public TransactionBean getTransactionBean() {
return transactionBean;
}
public void setTransactionBean(TransactionBean transactionBean) {
this.transactionBean = transactionBean;
}
public String logmetoo(){
System.out.println("Inside logmetoo");
getTransactionBean().setUsername("usename");
getTransactionBean().setPassword("password");
return SUCCESS;
}
}发布于 2014-09-02 20:42:16
有两种方法可以实例化transactionBean:
1)自己动手。这真的很简单:
public String logmetoo(){
System.out.println("Inside logmetoo");
setTransactionBean(new TransactionBean());
getTransactionBean().setUsername("gaurav");
getTransactionBean().setPassword("bhardwaj");
return Action.SUCCESS;
}2)在表单中添加输入字段,并使用name属性告诉操作类必须实例化字段。
<s:form action="displayActionlogmetoo.action" method="post">
<input type="text" name="transactionBean.userName"/>
<input type="text" name="transactionBean.password"/>
<s:submit method="logmetoo" key="login" align="center" />
</s:form>通过向服务器提交表单,struts将自动看到
name="transactionBean.userName"并执行以下代码:
displayLoginAction.setTransactionBean(new TransactionBean());
displayLoginAction.getTransactionBean().setUserName(*whatever is filled in in the input*);这不是魔法,它是由param拦截器为您自动完成的。param拦截器是拦截器默认堆栈的一部分。
https://stackoverflow.com/questions/25631549
复制相似问题