httpcomponent4.0調用樣例

private static class HttpComponentUtil {


private static int timeout = 5 * 1000;
private static PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
private static HttpClient httpClient;


static {
connManager.setMaxTotal(500);
connManager.setDefaultMaxPerRoute(100);
httpClient = HttpClients.custom().setConnectionManager(connManager).build();
}


public static String reqForGet(String url, String charset) throws Exception {


RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(timeout)
.setSocketTimeout(timeout).setConnectionRequestTimeout(timeout).build();


HttpGet httpGet = new HttpGet(url);
httpGet.setConfig(requestConfig);


HttpResponse response = httpClient.execute(httpGet);
return EntityUtils.toString(response.getEntity(), charset);
}
}

java.net的HttpUrlConnection作爲httpclient的調用樣例：

package com.nicchagil.util.httprequestor;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.URL;
import java.net.URLConnection;
import java.util.Iterator;
import java.util.Map;


public class HttpRequestor {
    
    private String charset = "utf-8";
    private Integer connectTimeout = null;
    private Integer socketTimeout = null;
    private String proxyHost = null;
    private Integer proxyPort = null;
    
    /**
     * Do GET request
     * @param url
     * @return
     * @throws Exception
     * @throws IOException
     */
    public String doGet(String url) throws Exception {
        
        URL localURL = new URL(url);
        
        URLConnection connection = openConnection(localURL);
        HttpURLConnection httpURLConnection = (HttpURLConnection)connection;
        
        httpURLConnection.setRequestProperty("Accept-Charset", charset);
        httpURLConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        
        InputStream inputStream = null;
        InputStreamReader inputStreamReader = null;
        BufferedReader reader = null;
        StringBuffer resultBuffer = new StringBuffer();
        String tempLine = null;
        
        if (httpURLConnection.getResponseCode() >= 300) {
            throw new Exception("HTTP Request is not success, Response code is " + httpURLConnection.getResponseCode());
        }
        
        try {
            inputStream = httpURLConnection.getInputStream();
            inputStreamReader = new InputStreamReader(inputStream);
            reader = new BufferedReader(inputStreamReader);
            
            while ((tempLine = reader.readLine()) != null) {
                resultBuffer.append(tempLine);
            }
            
        } finally {
            
            if (reader != null) {
                reader.close();
            }
            
            if (inputStreamReader != null) {
                inputStreamReader.close();
            }
            
            if (inputStream != null) {
                inputStream.close();
            }
            
        }

        return resultBuffer.toString();
    }
    
    /**
     * Do POST request
     * @param url
     * @param parameterMap
     * @return
     * @throws Exception 
     */
    public String doPost(String url, Map parameterMap) throws Exception {
        
        /* Translate parameter map to parameter date string */
        StringBuffer parameterBuffer = new StringBuffer();
        if (parameterMap != null) {
            Iterator iterator = parameterMap.keySet().iterator();
            String key = null;
            String value = null;
            while (iterator.hasNext()) {
                key = (String)iterator.next();
                if (parameterMap.get(key) != null) {
                    value = (String)parameterMap.get(key);
                } else {
                    value = "";
                }
                
                parameterBuffer.append(key).append("=").append(value);
                if (iterator.hasNext()) {
                    parameterBuffer.append("&");
                }
            }
        }
        
        System.out.println("POST parameter : " + parameterBuffer.toString());
        
        URL localURL = new URL(url);
        
        URLConnection connection = openConnection(localURL);
        HttpURLConnection httpURLConnection = (HttpURLConnection)connection;
        
        httpURLConnection.setDoOutput(true);
        httpURLConnection.setRequestMethod("POST");
        httpURLConnection.setRequestProperty("Accept-Charset", charset);
        httpURLConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        httpURLConnection.setRequestProperty("Content-Length", String.valueOf(parameterBuffer.length()));
        
        OutputStream outputStream = null;
        OutputStreamWriter outputStreamWriter = null;
        InputStream inputStream = null;
        InputStreamReader inputStreamReader = null;
        BufferedReader reader = null;
        StringBuffer resultBuffer = new StringBuffer();
        String tempLine = null;
        
        try {
            outputStream = httpURLConnection.getOutputStream();
            outputStreamWriter = new OutputStreamWriter(outputStream);
            
            outputStreamWriter.write(parameterBuffer.toString());
            outputStreamWriter.flush();
            
            if (httpURLConnection.getResponseCode() >= 300) {
                throw new Exception("HTTP Request is not success, Response code is " + httpURLConnection.getResponseCode());
            }
            
            inputStream = httpURLConnection.getInputStream();
            inputStreamReader = new InputStreamReader(inputStream);
            reader = new BufferedReader(inputStreamReader);
            
            while ((tempLine = reader.readLine()) != null) {
                resultBuffer.append(tempLine);
            }
            
        } finally {
            
            if (outputStreamWriter != null) {
                outputStreamWriter.close();
            }
            
            if (outputStream != null) {
                outputStream.close();
            }
            
            if (reader != null) {
                reader.close();
            }
            
            if (inputStreamReader != null) {
                inputStreamReader.close();
            }
            
            if (inputStream != null) {
                inputStream.close();
            }
            
        }

        return resultBuffer.toString();
    }

    private URLConnection openConnection(URL localURL) throws IOException {
        URLConnection connection;
        if (proxyHost != null && proxyPort != null) {
            Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(proxyHost, proxyPort));
            connection = localURL.openConnection(proxy);
        } else {
            connection = localURL.openConnection();
        }
        return connection;
    }
    
    /**
     * Render request according setting
     * @param request
     */
    private void renderRequest(URLConnection connection) {
        
        if (connectTimeout != null) {
            connection.setConnectTimeout(connectTimeout);
        }
        
        if (socketTimeout != null) {
            connection.setReadTimeout(socketTimeout);
        }
        
    }

    /*
     * Getter & Setter
     */
    public Integer getConnectTimeout() {
        return connectTimeout;
    }

    public void setConnectTimeout(Integer connectTimeout) {
        this.connectTimeout = connectTimeout;
    }

    public Integer getSocketTimeout() {
        return socketTimeout;
    }

    public void setSocketTimeout(Integer socketTimeout) {
        this.socketTimeout = socketTimeout;
    }

    public String getProxyHost() {
        return proxyHost;
    }

    public void setProxyHost(String proxyHost) {
        this.proxyHost = proxyHost;
    }

    public Integer getProxyPort() {
        return proxyPort;
    }

    public void setProxyPort(Integer proxyPort) {
        this.proxyPort = proxyPort;
    }

    public String getCharset() {
        return charset;
    }

    public void setCharset(String charset) {
        this.charset = charset;
    }
    
}

HttpRequestor