@PathVariable映射出现错误: Name for argument type

关于spring java.lang.IllegalArgumentException: Name for argument type [java.lang.String] 的错误
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为了这个问题费了很大劲，主要参考了了
1.[url]http://stackoverflow.com/questions/2622018/compile-classfile-issue-in-spring-3[/url] 这个主要是因为ant编译导致类似的问题。

2. [url]http://stackoverflow.com/questions/10305592/error-class-names-are-only-accepted-if-annotation-processing-is-explicitly-req[/url] 一开始src的写法有些问题，改为上面的写法便可。


发现问题：
一次做下载过程中，使用get方式进行下载，

@ResponseBody
    @RequestMapping(value = "/down/{_listid}/{type}", method = RequestMethod.GET)
    public ResponseEntity<byte[]> download(@PathVariable String _listid, @PathVariable String type) throws IOException {
    	......
    }

在idea和eclipse下面启动工程没问题， 但是部署的时候就出了问题，后台一直提示500错误，但看不到错误细节，后来我直接复制地址，打开标签，直接粘贴url，才看到下面错误：

[color=gray]org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.IllegalArgumentException: Name for argument type [java.lang.String] not available, and parameter name information not found in class file either.

org.springframework.web.servlet.FrameworkServlet.finalizeProcessing(FrameworkServlet.java:947)

org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:893)

org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:781)

javax.servlet.http.HttpServlet.service(HttpServlet.java:624)

javax.servlet.http.HttpServlet.service(HttpServlet.java:731)

org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)

org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:83)

com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)

com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)

root cause

java.lang.IllegalArgumentException: Name for argument type [java.lang.String] not available, and parameter name information not found in class file either.

org.springframework.util.Assert.notNull(Assert.java:112)

org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.updateNamedValueInfo(AbstractNamedValueMethodArgumentResolver.java:134)

org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.getNamedValueInfo(AbstractNamedValueMethodArgumentResolver.java:112)

org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:81)

org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:75)

org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:156)

org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:117)

org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97)

org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:647)

org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:603)

org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)

org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:950)

org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:859)

org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:883)

org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:781)

javax.servlet.http.HttpServlet.service(HttpServlet.java:624)

javax.servlet.http.HttpServlet.service(HttpServlet.java:731)

org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)

org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:83)

com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)

com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)[/color]

[b][color=red]org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.IllegalArgumentException: Name for argument type [java.lang.String] not available, and parameter name information not found in class file either.[/color][/b]

[color=red][b]原因：[/b][/color]

这个错误主要是因为action的参数标注默认是debug级别，比如

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

[color=red]此时userName的级别时debug级别，而在linux下编译时是忽略了这些标注，导致请求时就会找不到userName的参数。eclipse默认是debug级别的函数里面的参数名保留，但是ant编译就不行了。[/color]

[color=red][b]解决方法1:写全@RequestParam的参数 [/b][/color]

@RequestMapping("hello")
	public String helloWorld(Map<String, Object> map, HttpServletRequest request,@RequestParam(value="hhh", required = false) String hhh) {

		System.out.println("hello");
		System.out.println("["+hhh+"]");
		map.put("message", "test message111");
		return "helloView";
	}

写全@PathVariable的参数

@RequestMapping(value="/users/{userId}/topics/{topicId}")
public String test(
       @PathVariable(value="userId") int userId, 
       @PathVariable(value="topicId") int topicId)

[color=red][b]解决方法2:修改build.xml,使用javac debug=true [/b][/color]

<javac srcdir="${src}" destdir="${build}/WEB-INF/classes" debug="true" encoding="utf-8" classpathref="classpath" includeantruntime="on">
		</javac>