springmvc绑定参数出现的异常

转自：http://tiannet.iteye.com/blog/722838

在使用SpringMVC绑定基本类型（如String,Integer等）参数时，应通过@RequestParam注解指定具体的参数名称，否则，当源代码在非debug模式下编译后，运行时会引发HandlerMethodInvocationException异常，这是因为只有在debug模式下编译，其参数名称才存储在编译好的代码中。 

譬如下面的代码会引发异常： 

@RequestMapping(value = "/security/login", method = RequestMethod.POST)
public ModelAndView login(@RequestParam String userName, @RequestParam String password,
    HttpServletRequest request) {
    ......................

如果使用Eclipse编译不会在运行时出现异常，这是因为Eclipse默认是采用debug模式编译的，但是如果使用Ant通过javac任务编译的话就会出现异常，除非指定debug=”true”。出现的异常如同： 
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.web.bind.annotation.support.HandlerMethodInvocationException: Failed to invoke handler method [public org.springframework.web.servlet.ModelAndView com.mypackage.security.controller.LoginController.login(java.lang.String,java.lang.String,javax.servlet.http.HttpServletRequest)]; nested exception is java.lang.IllegalStateException: No parameter name specified for argument of type [java.lang.String], and no parameter name information found in class file either. 
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:659) 
.......... 

org.springframework.web.bind.annotation.support.HandlerMethodInvocationException: Failed to invoke handler method [public org.springframework.web.servlet.ModelAndView com.mypackage.security.controller.LoginController.login(java.lang.String,java.lang.String,javax.servlet.http.HttpServletRequest)]; nested exception is java.lang.IllegalStateException: No parameter name specified for argument of type [java.lang.String], and no parameter name information found in class file either. 
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
.......... 


java.lang.IllegalStateException: No parameter name specified for argument of type [java.lang.String], and no parameter name information found in class file either. 
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.getRequiredParameterName(HandlerMethodInvoker.java:618)
.......... 

最好的做法是通过@RequestParam注解指定具体的参数名称，如，上面的代码应该如此编写（注意@RequestParam部分）： 

@RequestMapping(value = "/security/login", method = RequestMethod.POST)
public ModelAndView login(@RequestParam("userName") String userName,
    @RequestParam("password") String password,
    HttpServletRequest request) {
    ......................