struts1.2 actionform对象为空
刚接触struts1 ,做了一个简单的登陆例子,但是报空指针错误!断点调试了下actionform对象为空!一直没找出错误,求解。

login.jsp页面代码

Java code

<div id="b">
    <form action="login.do" method="post">
        用户名：<input name="username" type="text" /><br />
        密  码 ：<input name="password" type="password" /><br />
        &nbsp;&nbsp;&nbsp;&nbsp;      
       <input name="ok" type="submit" value=""  style="background-image:url(images/66.gif);height:30px;width:80px;border:0;"/>
     </form>
</div>]

action类：

Java code

public class LoginAction extends Action {
    @Override
    public ActionForward execute(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        // TODO Auto-generated method stub
        
        userLogin u=(userLogin)form;
        if(u.getUsername().equals("mandy")&&u.getPassword().equals("123"))
        {
            return mapping.findForward("index.jsp");
        }
        return super.execute(mapping, form, request, response);
    }

actionform类：

public class userLogin extends ActionForm {
private String username;
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}

struts-config.xml文件配置：
<struts-config>
 
  <form-beans>
<form-bean name="userLogin" type="com.mycompany.struts"></form-bean>
</form-beans>
<action-mappings>
<action path="/login" type="com.mycompany.struts.LoginAction" name="userLogin">
<forward name="success" path="/index.jsp"></forward>
</action>
</action-mappings>
  <message-resources parameter="com.mycompany.struts.ApplicationResources" />
</struts-config>

web.xml配置

<servlet>
  <servlet-name>action</servlet-name>
  <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
  <init-param>
  <param-name>config</param-name>
  <param-value>/WEB-INF/struts-config.xml</param-value>
  </init-param>
  <init-param>
  <param-name>debug</param-name>
  <param-value>3</param-value>
  </init-param>
  <init-param>
  <param-name>detail</param-name>
  <param-value>3</param-value>
  </init-param>
  <load-on-startup>0</load-on-startup>
  </servlet>
  <servlet-mapping>
  <servlet-name>action</servlet-name>
  <url-pattern>*.do</url-pattern>
  </servlet-mapping>

------解决方案--------------------
<form-bean name="userLogin" type="