java 增强 request 和 response 功能

package me.gacl.web.filter;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;

/**
* @ClassName: AdvancedFilter
* @Description: 这个过滤器是用来解决中文乱码，转义内容中的html标签，过滤内容中的敏感字符的
* @author: 孤傲苍狼
* @date: 2014-9-6 下午6:17:37
*
*/ 
public class AdvancedFilter implements Filter {

    private FilterConfig filterConfig = null;
    //设置默认的字符编码
    private String defaultCharset = "UTF-8";

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        //得到过滤器的初始化配置信息
        this.filterConfig = filterConfig;
    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse resp,
            FilterChain chain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) resp;
        //得到在web.xml中配置的字符编码
        String charset = filterConfig.getInitParameter("charset");
        if(charset==null){
            charset = defaultCharset;
        }
        request.setCharacterEncoding(charset);
        response.setCharacterEncoding(charset);
        response.setContentType("text/html;charset="+charset);

        AdvancedRequest requestWrapper = new AdvancedRequest(request);
        chain.doFilter(requestWrapper, response);
    }

    @Override
    public void destroy() {

    }

    class AdvancedRequest extends HttpServletRequestWrapper{

        private List
 
   dirtyWords = getDirtyWords();

        //定义一个变量记住被增强对象(request对象是需要被增强的对象)
        private HttpServletRequest request;
        //定义一个构造函数，接收被增强对象
        public AdvancedRequest(HttpServletRequest request) {
            super(request);
            this.request = request;
        }
        /* 覆盖需要增强的getParameter方法
         * @see javax.servlet.ServletRequestWrapper#getParameter(java.lang.String)
         */
        @Override
        public String getParameter(String name) {
            try{
                //获取参数的值
                String value= this.request.getParameter(name);
                if(value==null){
                    return null;
                }
                //如果不是以get方式提交数据的，就直接返回获取到的值
                if(!this.request.getMethod().equalsIgnoreCase("get")) {
                    //调用filter转义value中的html标签
                    value= filter(value);
                }else{
                    //如果是以get方式提交数据的，就对获取到的值进行转码处理
                    value = new String(value.getBytes("ISO8859-1"),this.request.getCharacterEncoding());
                    //调用filter转义value中的html标签
                    value= filter(value);
                }

                for(String dirtyWord : dirtyWords){
                    if(value.contains(dirtyWord)){
                        System.out.println("内容中包含敏感词："+dirtyWord+"，将会被替换成****");
                        //替换敏感字符
                        value = value.replace(dirtyWord, "****");
                    }
                }
                return value;
            }catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }

    /**
    * @Method: filter
    * @Description: 过滤内容中的html标签
    * @Anthor:孤傲苍狼
    * @param value
    * @return
    */ 
    public String filter(String value) {
        if (value == null){
            return null;
        }
        char content[] = new char[value.length()];
        value.getChars(0, value.length(), content, 0);
        StringBuffer result = new StringBuffer(content.length + 50);
        for (int i = 0; i < content.length; i++) {
            switch (content[i]) {
            case '<':
                result.append("<");
                break;
            case '>':
                result.append(">");
                break;
            case '&':
                result.append("&");
                break;
            case '"':
                result.append(""");
                break;
            default:
                result.append(content[i]);
            }
        }
        return (result.toString());
    }

    /**
    * @Method: getDirtyWords
    * @Description: 获取敏感字符
    * @Anthor:孤傲苍狼
    *
    * @return
    */ 
    private List
  
    getDirtyWords(){ List
   
     dirtyWords = new ArrayList
    
     (); String dirtyWordPath = filterConfig.getInitParameter("dirtyWord"); InputStream inputStream = filterConfig.getServletContext().getResourceAsStream(dirtyWordPath); InputStreamReader is = null; try { is = new InputStreamReader(inputStream,defaultCharset); } catch (UnsupportedEncodingException e2) { e2.printStackTrace(); } BufferedReader reader = new BufferedReader(is); String line; try { while ((line = reader.readLine())!= null) {//如果 line为空说明读完了 dirtyWords.add(line); } } catch (IOException e) { e.printStackTrace(); } return dirtyWords; } } 
      
      
       AdvancedFilter
       
      
       me.gacl.web.filter.AdvancedFilter
       
       
       
        charset
        
       
        UTF-8
        //中文乱码解决 
       
       
       
        dirtyWord
        
       
        /WEB-INF/DirtyWord.txt
        //敏感字符路径 
       
      
      
      
       AdvancedFilter
       
      
       /*
       
     
    
   
  
 

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.zip.GZIPOutputStream;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;

/**
* @ClassName: GzipFilter
* @Description: 压缩过滤器，将web应用中的文本都经过压缩后再输出到浏览器
* @author: 孤傲苍狼
* @date: 2014-9-7 上午10:52:42
*
*/ 
public class GzipFilter implements Filter {

    public void doFilter(ServletRequest req, ServletResponse resp,
            FilterChain chain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) resp;

        BufferResponse myresponse = new BufferResponse(response);
        chain.doFilter(request, myresponse);
        //拿出缓存中的数据，压缩后再打给浏览器
        byte out[] = myresponse.getBuffer();
        System.out.println("原始大小:" + out.length);

        ByteArrayOutputStream bout = new ByteArrayOutputStream();
        //压缩输出流中的数据
        GZIPOutputStream gout = new GZIPOutputStream(bout);
        gout.write(out);
        gout.close();

        byte gzip[] = bout.toByteArray();
        System.out.println("压缩后的大小:" + gzip.length);

        response.setHeader("content-encoding", "gzip");
        response.setContentLength(gzip.length);
        response.getOutputStream().write(gzip);
    }

    public void destroy() {

    }

    public void init(FilterConfig filterConfig) throws ServletException {

    }
}

class BufferResponse extends HttpServletResponseWrapper{

    private ByteArrayOutputStream bout = new ByteArrayOutputStream();
    private PrintWriter pw;
    private HttpServletResponse response;
    public BufferResponse(HttpServletResponse response) {
        super(response);
        this.response = response;
    }
    @Override
    public ServletOutputStream getOutputStream() throws IOException {
        return new MyServletOutputStream(bout);
    }
    @Override
    public PrintWriter getWriter() throws IOException {
        pw = new PrintWriter(new OutputStreamWriter(bout,this.response.getCharacterEncoding()));
        return pw;
    }

    public byte[] getBuffer(){
        try{
            if(pw!=null){
                pw.close();
            }
            if(bout!=null){
                bout.flush();
                return bout.toByteArray();
            }


            return null;
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

class MyServletOutputStream extends ServletOutputStream{

    private ByteArrayOutputStream bout;
    public MyServletOutputStream(ByteArrayOutputStream bout){
        this.bout = bout;
    }

    @Override
    public void write(int b) throws IOException {
        this.bout.write(b);
    }
}
　　



 
      
  
   配置压缩过滤器
  
      
  
   GzipFilter
  
      
  
   me.gacl.web.filter.GzipFilter
  
  
 

  
 
  
 
      
  
   GzipFilter
  
      
  
   *.jsp
  
      
  
      
  
      
  
   FORWARD
  
      
  
      
  
   REQUEST
  
  
 
  
 
  
 
      
  
   GzipFilter
  
      
  
   *.js
  
  
 
  
 
  
 
      
  
   GzipFilter
  
      
  
   *.css
  
  
 
  
 
  
 
      
  
   GzipFilter
  
      
  
   *.html
  
  
 

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;

/**
* @ClassName: WebResourceCachedFilter
* @Description: Web资源缓存过滤器
* @author: 孤傲苍狼
* @date: 2014-9-8 上午12:20:16
*
*/ 
public class WebResourceCachedFilter implements Filter {
    /**
    * @Field: map
    *          缓存Web资源的Map容器
    */ 
    private Map
 
   map = new HashMap
  
   (); @Override public void init(FilterConfig filterConfig) throws ServletException { } @Override public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) resp; //1.得到用户请求的uri String uri = request.getRequestURI(); //2.看缓存中有没有uri对应的数据 byte b[] = map.get(uri); //3.如果缓存中有，直接拿缓存的数据打给浏览器，程序返回 if(b!=null){ //根据字节数组和指定的字符编码构建字符串 String webResourceHtmlStr = new String(b,response.getCharacterEncoding()); System.out.println(webResourceHtmlStr); response.getOutputStream().write(b); return; } //4.如果缓存没有，让目标资源执行，并捕获目标资源的输出 BufferResponse myresponse = new BufferResponse(response); chain.doFilter(request, myresponse); //获取缓冲流中的内容的字节数组 byte out[] = myresponse.getBuffer(); //5.把资源的数据以用户请求的uri为关键字保存到缓存中 map.put(uri, out); //6.把数据打给浏览器 response.getOutputStream().write(out); } @Override public void destroy() { } class BufferResponse extends HttpServletResponseWrapper{ private ByteArrayOutputStream bout = new ByteArrayOutputStream(); //捕获输出的缓存 private PrintWriter pw; private HttpServletResponse response; public BufferResponse(HttpServletResponse response) { super(response); this.response = response; } @Override public ServletOutputStream getOutputStream() throws IOException { return new MyServletOutputStream(bout); } @Override public PrintWriter getWriter() throws IOException { pw = new PrintWriter(new OutputStreamWriter(bout,this.response.getCharacterEncoding())); return pw; } public byte[] getBuffer(){ try{ if(pw!=null){ pw.close(); } return bout.toByteArray(); }catch (Exception e) { throw new RuntimeException(e); } } } class MyServletOutputStream extends ServletOutputStream{ private ByteArrayOutputStream bout; public MyServletOutputStream(ByteArrayOutputStream bout){ //接收数据写到哪里 this.bout = bout; } @Override public void write(int b) throws IOException { bout.write(b); } } } 
    
    
     Web资源缓存过滤器
     
    
     WebResourceCachedFilter
     
    
     me.gacl.web.filter.WebResourceCachedFilter
     
    
    
    
     WebResourceCachedFilter
     
     
    
     /login.jsp
     
    
     /test.jsp
     
    
     /test2.jsp