HttpUtil工具类

今天药忘吃喽~ 2022-06-13 12:37 218阅读 0赞

原文：[http://zhelong111.iteye.com/blog/1407117][http_zhelong111.iteye.com_blog_1407117]

/**
     * 增强型Http辅助类
     * @author zhouli
     *
     */
    public class EnhancedHttpUtil { 
    	
    	private static HttpClient httpClient; 
    	private static final String TAG = "HttpUtil";
    	
    	/**
    	 * 获得线程安全的HttpClient对象，能够适应多线程环境
    	 * @return
    	 */
    	public static synchronized HttpClient getHttpClient() {
            if (null == httpClient) {
                HttpParams params = new BasicHttpParams();
                // 设置一些基本参数
                HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
                HttpProtocolParams.setContentCharset(params,
                        "UTF-8");
                HttpProtocolParams.setUseExpectContinue(params, true);
                HttpProtocolParams
                        .setUserAgent(
                                params,
                                "Mozilla/5.0(Linux;U;Android 2.2.1;en-us;Nexus One Build.FRG83) "
                                        + "AppleWebKit/553.1(KHTML,like Gecko) Version/4.0 Mobile Safari/533.1");
                // 超时设置
                /* 从连接池中取连接的超时时间 */
                ConnManagerParams.setTimeout(params, 1000);
                /* 连接超时 */
                HttpConnectionParams.setConnectionTimeout(params, 1000);
                /* 请求超时 */
                HttpConnectionParams.setSoTimeout(params, 4000);
              
                // 设置我们的HttpClient支持HTTP和HTTPS两种模式
                SchemeRegistry schReg = new SchemeRegistry();
                schReg.register(new Scheme("http", PlainSocketFactory
                        .getSocketFactory(), 80));
                schReg.register(new Scheme("https", SSLSocketFactory
                        .getSocketFactory(), 443));
    
                // 使用线程安全的连接管理来创建HttpClient
                ClientConnectionManager conMgr = new ThreadSafeClientConnManager(
                        params, schReg);
                httpClient = new DefaultHttpClient(conMgr, params);
            }
            return httpClient;
        }
    	
    	/**
    	 * 获得Post请求对象
    	 * @param uri 请求地址，也可以带参数
    	 * @param params 如果为null，则不添加由BasicNameValue封装的参数
    	 * @return
    	 */
    	public static HttpPost getPost(String uri, List<BasicNameValuePair> params) {
    		HttpPost post = new HttpPost(uri);
    		try {
    			if(params != null) {
    				post.setEntity(new UrlEncodedFormEntity(params));
    			}
    		} catch (UnsupportedEncodingException e) { 
    			e.printStackTrace();
    		}
    		return post;		
    	}
    	
    	/**
    	 * 用户使用的方法
    	 * 功能：从服务器获得字符串
    	 * @param post
    	 * @return
    	 */
    	public static String getString(HttpPost post) {
    		
    		HttpClient httpClient = getHttpClient();
    		HttpResponse response;
    		try {
    			response = httpClient.execute(post);
    			if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
    				post.abort();
    				Log.v(TAG, "响应失败,请求终止.");
    				return null;
    			} 
    			Log.v(TAG, "响应成功.");
    			return EntityUtils.toString(response.getEntity());
    		} catch (ClientProtocolException e) { 
    			e.printStackTrace();
    			Log.e(TAG, e.getMessage());
    			return null;
    		} catch (IOException e) { 
    			e.printStackTrace();
    			Log.e(TAG, e.getMessage());
    			return null;
    		} 
    	}
    	
    	/**
    	 * 用户使用的方法
    	 * 功能：请求服务器，返回字符串
    	 * @param post post 请求对象
    	 * @param requestLimit 请求失败限制次数
    	 * @return
    	 */
    	public static String getString(HttpPost post, int requestLimit) {
    		
    		if (requestLimit < 1) {
    			return null;
    		}
    		HttpResponse response;
    		int currCount = 0; // 当前请求次数
    		String result = null;
    		
    		while (currCount < requestLimit) {
    			
    			HttpClient httpClient = getHttpClient();
    			currCount++;
    			try {
    				response = httpClient.execute(post);
    				if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
    					Log.v(TAG, "响应成功.");
    					return EntityUtils.toString(response.getEntity());
    				} else {
    					post.abort();
    					Log.v(TAG, "响应失败,请求终止."); 
    					result = "响应失败,请求终止.";
    				} 
    			} catch (ClientProtocolException e) {  
    				Log.e(TAG, e.getMessage());
    				if (currCount > requestLimit) {
    					result = "请求失败."; 
    					break;
    				} 
    				System.out.println("ClientProtocolException");
    			} catch (IOException e) {  
    				Log.e(TAG, e.getMessage());
    				if (e instanceof ConnectTimeoutException) {
    					result = "连接超时.";
    				} else {
    					result = "IO异常.";
    				}
    				if (currCount > requestLimit) {	
    					break;
    				}
    				System.out.println("IOException");
    			} finally {
    				System.out.println("finally"); 
    			}
    		}
    		return result;
    	}
    	
    	/**
    	 * 用户使用的方法
    	 * 功能：请求服务器，返回字符串
    	 * @param uri 字符串形式的请求地址
    	 * @param requestLimit 最多允许的请求失败次数
    	 * @return
    	 */
    	public static String getString(String uri, int requestLimit) {   
    		
    		if (requestLimit < 1) {
    			return null;
    		}
    		HttpResponse response;
    		int currCount = 0; // 当前请求次数
    		String result = null;
    		HttpPost post = getPost(uri, null);
    		while (currCount < requestLimit) {
    			
    			HttpClient httpClient = getHttpClient();
    			currCount++;
    			try {
    				response = httpClient.execute(post);
    				if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
    					Log.v(TAG, "响应成功.");
    					return EntityUtils.toString(response.getEntity());
    				} else {
    					post.abort();
    					Log.v(TAG, "响应失败,请求终止."); 
    					result = "响应失败,请求终止.";
    				} 
    			} catch (ClientProtocolException e) {  
    				Log.e(TAG, e.getMessage());
    				if (currCount > requestLimit) {
    					result = "请求失败."; 
    					break;
    				} 
    				System.out.println("ClientProtocolException");
    			} catch (IOException e) {  
    				//Log.e(TAG, e.getMessage());
    				if (e instanceof ConnectTimeoutException) {
    					result = "连接超时.";
    				} else {
    					result = "IO异常.";
    				}
    				if (currCount > requestLimit) {	
    					break;
    				}
    				//System.out.println("IOException");
    			} finally {
    				System.out.println("finally"); 
    			}
    		}
    		return result;
    	}
    	
    	/**
    	 * 释放建立http请求占用的资源
    	 */
    	public static void shutdown() { 
    		// 释放建立http请求占用的资源
    		httpClient.getConnectionManager().shutdown();
    		httpClient = null;
    	}
    }

使用范例：

package com.laili;
    
    import java.util.ArrayList;
    import java.util.List; 
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.message.BasicNameValuePair; 
    import android.app.Activity;
    import android.os.Bundle;
    import android.os.Handler;
    import android.os.Message;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText; 
    import com.laili.util.HttpUtil;
    
    public class HttpUtilActivity extends Activity {
       
    	private Button btn;
    	private EditText show;
    	private String uri = "http://10.2.105.76:8080/json/TestJsonServlet";
    	private List<BasicNameValuePair> params;
        private Handler handler;
        private String showStr = "";
        
    	@Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            
            params = new ArrayList<BasicNameValuePair>();
            
            handler = new Handler() {
            	@Override
            	public void handleMessage(Message msg) {
            		switch (msg.what) {
            		case 0x01:
            			show.setText(showStr); 
            			break;
            		}
            	}
            };
            
            show = (EditText) findViewById(R.id.editText1);
            btn = (Button) findViewById(R.id.button1);
            btn.setOnClickListener(new OnClickListener() {
    			
    			@Override
    			public void onClick(View v) {
    				new Thread(){
    					public void run() { 
    						params.add(new BasicNameValuePair("username", "zhelong"));
    						params.add(new BasicNameValuePair("password", "123456"));
    						HttpPost post = HttpUtil.getPost(uri, params);
    						showStr += HttpUtil.getString(post,3); 
    						//System.out.println(response);
    						handler.sendEmptyMessage(0x01);
    					};
    				}.start();
    			}
    		});
        }
    }

[http_zhelong111.iteye.com_blog_1407117]: http://zhelong111.iteye.com/blog/1407117