跑在Web容器中的話
可以在監聽器中直接初始化HC
之後就可以用static方法進行調用
用做entity內容獲取

Code如下:

public class ThreadHttpClient {
    private static Logger logger = Logger.getLogger(ThreadHttpClient.class);
    private static ThreadHttpClient threadhttpclient;
    private DefaultHttpClient httpclient;
    public static void load(){
        threadhttpclient = new ThreadHttpClient();
    }
    public static ThreadHttpClient getInstance() {
        if(threadhttpclient == null){
            load();
        }
        return threadhttpclient;
    }
    public void initHttp() {
        logger.info("init ThreadHttpClient...");
        //設置最大連接數
        PoolingClientConnectionManager cm = new PoolingClientConnectionManager();
        int maxTotal = 128;
        cm.setMaxTotal(maxTotal);
        this.httpclient = new DefaultHttpClient(cm);
    }   
    public void shutHttp(){
        if(null != httpclient){
            logger.info("關閉HttpClient多線程處理");
            httpclient.getConnectionManager().shutdown(); 
        }
    }
    public DefaultHttpClient getHttpclient() {
        return httpclient;
    }
    public void setHttpclient(DefaultHttpClient httpclient) {
        this.httpclient = httpclient;
    }
}

public class ClientHttp {
    private static Logger logger = Logger.getLogger(ClientHttp.class);
    /**
     * 不帶參數的Get方法
     * @param  httpUrl
     *      鏈接地址
     * @return HTTP響應的字符串
     */
     
    public static String doGet(String httpUrl){
        DefaultHttpClient http=ThreadHttpClient.getInstance().getHttpclient();
        //設置超時時間
        setTimeout(http);
        //設置Get地址
        HttpGet get=new HttpGet(httpUrl);
        String entity = "";
        HttpResponse response=null;
        //開始發送請求獲取數據
        try{
            response=http.execute(get);
            if (response.getStatusLine().getStatusCode() == 200) {
                entity=EntityUtils.toString(response.getEntity());
            }else{
                logger.error("GET請求返回失敗");
                entity = "ErrorCode:0001";
            }
        }catch(org.apache.http.conn.ConnectTimeoutException e1){
            logger.error("HttpClient發送請求超時");
            entity = "ErrorCode:0011";
        }catch(java.net.SocketTimeoutException e2){
            logger.error("HttpClient讀取數據超時");
            entity = "ErrorCode:0100";
        }catch(Exception e){
            logger.error("GET請求發送失敗:"+e.toString());
            entity = "ErrorCode:0010";
        }finally{
            //釋放鏈接
            get.abort();
        }
        return entity;
    }
     
    /**
     * 帶參數的Get方法
     * @param  httpUrl
     *      鏈接地址
     * @param  parameters
     *      參數 x=y&z=a...
     * @return HTTP響應的字符串/出錯信息
     */
    public static String doGet(String httpUrl,String parameters){
        DefaultHttpClient http=ThreadHttpClient.getInstance().getHttpclient();
        //設置超時時間
        setTimeout(http);
        //設置Get地址
        httpUrl=httpUrl+"?"+parameters;
        HttpGet get=new HttpGet(httpUrl);
        String entity = "";
        HttpResponse response=null;
        //開始發送請求獲取數據
        try{
            response=http.execute(get);
            if (response.getStatusLine().getStatusCode() == 200) {
                entity=EntityUtils.toString(response.getEntity());
            }else{
                logger.error("GET請求返回失敗");
                entity = "ErrorCode:0001";
            }
        }catch(org.apache.http.conn.ConnectTimeoutException e1){
            logger.error("HttpClient發送請求超時");
            entity = "ErrorCode:0011";
        }catch(java.net.SocketTimeoutException e2){
            logger.error("HttpClient讀取數據超時");
            entity = "ErrorCode:0100";
        }catch(Exception e){
            logger.error("GET請求發送失敗:"+e.toString());
            entity = "ErrorCode:0010";
        }finally{
            //釋放鏈接
            get.abort();
        }
        return entity;
    }
     
    /**
     * 帶參數的Get方法
     * @param  httpUrl
     *      鏈接地址
     * @param  parameters  
     *      類型:Map
     * @return HTTP響應的字符串
     */
    public static String doGet(String httpUrl,Map<String,String> parameters){
        DefaultHttpClient http=ThreadHttpClient.getInstance().getHttpclient();
        //設置超時時間
        setTimeout(http);
        //設置Get地址
        httpUrl=httpUrl+"?";
        Iterator it = parameters.entrySet().iterator(); 
        int count=0;
        while(it.hasNext()){
            if(count==0){
                count++;
            }else{
                httpUrl=httpUrl+"&";
            }
            Map.Entry m=(Map.Entry)it.next(); 
            httpUrl=httpUrl+m.getKey()+"="+m.getValue();
        } 
        logger.info("請求地址組織完畢 : " + httpUrl);
        HttpGet get=new HttpGet(httpUrl);
        String entity = "";
        HttpResponse response=null;
        //開始發送請求獲取數據
        try{
            response=http.execute(get);
            if (response.getStatusLine().getStatusCode() == 200) {
                entity=EntityUtils.toString(response.getEntity());
            }else{
                logger.error("GET請求返回失敗");
                entity = "ErrorCode:0001";
            }
        }catch(org.apache.http.conn.ConnectTimeoutException e1){
            logger.error("HttpClient發送請求超時");
            entity = "ErrorCode:0011";
        }catch(java.net.SocketTimeoutException e2){
            logger.error("HttpClient讀取數據超時");
            entity = "ErrorCode:0100";
        }catch(Exception e){
            logger.error("GET請求發送失敗:"+e.toString());
            entity = "ErrorCode:0010";
        }finally{
            //釋放鏈接
            get.abort();
        }
        return entity;
    }
     
    /**
     * 帶參數的Post方法
     * @param  httpUrl
     *      鏈接地址
     * @param  parameters
     *      參數 x=y&z=a...
     * @param  StrCode  
     *      字符編碼
     * @return HTTP響應的字符串
     */
    public static String doPost(String httpUrl,String parameters,String StrCode){
        DefaultHttpClient http=ThreadHttpClient.getInstance().getHttpclient();
        //設置超時時間
        setTimeout(http);
        //設置Post地址
        HttpPost post=new HttpPost(httpUrl);
        //組織Post內容
        List<NameValuePair> params = new ArrayList<NameValuePair>(); 
        String para[]=parameters.split("&");
        for(int i=0;i<para.length;i++){
            params.add(new BasicNameValuePair(para[i].substring(0,para[i].indexOf("=")),para[i].substring(para[i].indexOf("=")+1)));
        }
        //發送請求
        String entity = "";
        HttpResponse response=null;
        //開始發送請求獲取數據
        try{
            post.setEntity(new UrlEncodedFormEntity(params,StrCode));
            response=http.execute(post);
            if (response.getStatusLine().getStatusCode() == 200) {
                entity=EntityUtils.toString(response.getEntity());
            }else{
                logger.error("POST請求返回失敗");
                entity = "ErrorCode:0001";
            }
        }catch(org.apache.http.conn.ConnectTimeoutException e1){
            logger.error("HttpClient發送請求超時");
            entity = "ErrorCode:0011";
        }catch(java.net.SocketTimeoutException e2){
            logger.error("HttpClient讀取數據超時");
            entity = "ErrorCode:0100";
        }catch(Exception e){
            logger.error("POST請求發送失敗:"+e.toString());
            entity = "ErrorCode:0010";
        }finally{
            //釋放鏈接
            post.abort();
        }
        return entity;
    }
     
    /**
     * 帶參數的Post方法
     * @param  httpUrl  鏈接地址
     * @param  parameters 參數Map
     * @param  StrCode  字符編碼
     * @return HTTP響應的字符串
     */
    public static String doPost(String httpUrl,Map<String,String> parameters,String StrCode){
        DefaultHttpClient http=ThreadHttpClient.getInstance().getHttpclient();
        //設置超時時間
        setTimeout(http);   
        //設置Post地址
        HttpPost post=new HttpPost(httpUrl);
        //組織Post內容
        List<NameValuePair> params = new ArrayList<NameValuePair>(); 
        Iterator it = parameters.entrySet().iterator(); 
        while(it.hasNext()){
            Map.Entry m=(Map.Entry)it.next(); 
            params.add(new BasicNameValuePair(m.getKey()+"",m.getValue()+""));
        } 
        //發送請求
        String entity = "";
        HttpResponse response=null;
        //開始發送請求獲取數據
        try{
            post.setEntity(new UrlEncodedFormEntity(params,StrCode));
            response=http.execute(post);
            if (response.getStatusLine().getStatusCode() == 200) {
                entity=EntityUtils.toString(response.getEntity());
            }else{
                logger.error("POST請求返回失敗");
                entity = "ErrorCode:0001";
            }
        }catch(org.apache.http.conn.ConnectTimeoutException e1){
            logger.error("HttpClient發送請求超時");
            entity = "ErrorCode:0011";
        }catch(java.net.SocketTimeoutException e2){
            logger.error("HttpClient讀取數據超時");
            entity = "ErrorCode:0100";
        }catch(Exception e){
            logger.error("POST請求發送失敗:"+e.toString());
            entity = "ErrorCode:0010";
        }finally{
            //釋放鏈接
            post.abort();
        }
        return entity;
    }
    public static void setTimeout(DefaultHttpClient http){
        //設置打開鏈接超時時間
        http.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 3000);
        //設置讀取數據超時超時時間
        http.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 5000);
    }
}