我的家園

這兩個異常如下：
java.lang.IllegalStateException: Cannot forward after response has been committed
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:313)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:301)
    at com.servlet.MyServlet2.doGet(MyServlet2.java:22)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.filter.MyFilter.doFilter(MyFilter.java:48)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:228)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
    at java.lang.Thread.run(Unknown Source)
 
java.lang.IllegalStateException
    at org.apache.catalina.connector.ResponseFacade.sendError(ResponseFacade.java:407)
    at org.apache.catalina.servlets.DefaultServlet.serveResource(DefaultServlet.java:662)
    at org.apache.catalina.servlets.DefaultServlet.doGet(DefaultServlet.java:325)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.filter.MyFilter.doFilter(MyFilter.java:48)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:228)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
    at java.lang.Thread.run(Unknown Source)
 
只要在重定向后加return就可以了。
public void doFilter(ServletRequest request, ServletResponse response,
        FilterChain chain) throws IOException, ServletException {
    request.setCharacterEncoding("UTF-8");
    response.setCharacterEncoding("UTF-8");        
    HttpServletRequest hrequest = (HttpServletRequest)request;
    String path = hrequest.getContextPath();
    String basePath = hrequest.getScheme()+"://"+hrequest.getServerName()+":"+hrequest.getServerPort()+path+"/";
    // 獲得請求的全路徑
    String reUrl = hrequest.getRequestURL().toString();
    // 是否包含參數
    int index = reUrl.indexOf("?");
    String re = "";
    if(index == -1){
        re = reUrl.substring(basePath.length());
    }else{
        re = reUrl.substring(basePath.length(), index);
    }
    // 是否是請求資源
    if(!isResource(re)){
        // 是否有訪問的權限
        boolean isCheck = ConnUril.checkUrl(re);
        if(!isCheck){
            request.getRequestDispatcher("/error.jsp").forward(request,response);
            // 必須加返回，否則報錯
            return ;
        }
    }
    // 繼續執行
    chain.doFilter(request, response);
}