由于最近在使用spring+jersey开发要设置基于servlet的filter。当在filter中通过request.getReader或者getInputStream读取body中的json参数处理时,由于rest风格的jersey框架底层亦是基于同样原理读取post请求body中参数。因为request自身的原则:getReader或者getInputStream只能调用其中一个且只有一次可以正常获取body中内容,导致在filter中通过getReader第一次读取body中参数成功,当放行时,jersey中控制器执行时候,会出现异常:
java.lang.IllegalStateException: getReader() has already been called for this request。
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### 运行系统:windows8
### JDK版本 : JDK1.7
### 框架:spring3x + jersey2.x
### 开发IDE:MyEclipse
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1.0 在web.xml中配置spring过滤器filter,集成自定义filter
DelegateFilter
org.springframework.web.filter.DelegatingFilterProxy
targetBeanName
myFilter
targetFilterLifecycle
true
DelegateFilter
/*
PS:若是在filter中想使用springIOC容器中其他bean.如其他service类。那么可以在该bean中配置。
例如在filter中需要注入公用commonSerivce
public class myFilter implements Filter{
private CommonService commonService;
//需要setter
.......
}
要想使用commonService而不抛出空指针异常,需要在bean中配置依赖:
3.0 自定义filter
原始代码与运行结果如下:
public class FilterPost implements Filter{
private Log log = LogFactory.getLog(FilterPost.class);
String param = "";
public void destroy() {
// TODO Auto-generated method stub
}
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = null;
if(req instanceof HttpServletRequest) {
request = (HttpServletRequest)req;
}
if("POST".equalsIgnoreCase(request.getMethod())){
param = this.getBodyString(request.getReader());
log.info("filter读取body中的参数>>>>>>>>>"+param);
chain.doFilter(request, res);
}
}
public void init(FilterConfig config) throws ServletException {
}
//获取request请求body中参数
public static String getBodyString(BufferedReader br) {
String inputLine;
String str = "";
try {
while ((inputLine = br.readLine()) != null) {
str += inputLine;
}
br.close();
} catch (IOException e) {
System.out.println("IOException: " + e);
}
return str;
}
4.0基于jersey的controller中post请求处理
@POST
@Path("/postJson")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public Map postByJson(Map jsonParam) {
JSONObject jo = new JSONObject(jsonParam);
System.out.println(jsonParam);
Map param = new HashMap();
param.put("name", jo.getString("name").length()==0? "" : jo.getString("name"));
param.put("age", jo.getString("age").length()==0 ? "" :jo.getString("age"));
param.put("status", "200");
param.put("Msg", "ok,success");
return param;
}
5. 抛出异常
java.lang.IllegalStateException: getReader() has already been called for this request
at org.apache.catalina.connector.Request.getInputStream(Request.java:1085)
结合JODD开源框架,且在Filter中将ServletRequest替换为ServletRequestWrapper 来解决该问题。
A:添加jodd支持:
在pom.xml中添加对jodd的依赖:
org.jodd
jodd-core
3.4.8
public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper{
private final byte[] body; //用于保存读取body中数据
public BodyReaderHttpServletRequestWrapper(HttpServletRequest request)
throws IOException {
super(request);
body = StreamUtil.readBytes(request.getReader(), "UTF-8");
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream bais = new ByteArrayInputStream(body);
return new ServletInputStream() {
@Override
public int read() throws IOException {
return bais.read();
}
@Override
public boolean isFinished() {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean isReady() {
// TODO Auto-generated method stub
return false;
}
@Override
public void setReadListener(ReadListener arg0) {
// TODO Auto-generated method stub
}
};
}
}
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
String method = "GET";
ServletRequest requestWrapper = null;
if(req instanceof HttpServletRequest) {
method = ((HttpServletRequest) req).getMethod();
requestWrapper = new BodyReaderHttpServletRequestWrapper((HttpServletRequest) req); //替换
}
if("POST".equalsIgnoreCase(method)){
param = this.getBodyString(requestWrapper.getReader());
log.info("filter读取body中的参数>>>>>>>>>"+param);
chain.doFilter(requestWrapper, res);
}
请求成功................
参考文章:http://liwx2000.iteye.com/blog/1542431