为Android封装的HTTP请求组件

package com.android.mall.net;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import com.android.mall.tool.Loger;

public class HTTP {
	
	/**
	 * 返回请求网络字符串数据
	 * 
	 * @param url
	 *            请求地址
	 * @param params
	 *            请求参数
	 * @param method
	 *            请求方法
	 * @return 字符串数据
	 */
	public static String getString(String url, Map<String, String> params, String method) {
		try {
			HttpClient httpClient = new DefaultHttpClient();
			HttpPost post = new HttpPost(url);
			if (params != null && params.size() > 0) {
				Iterator<String> iterator = params.keySet().iterator();
				List<BasicNameValuePair> requestParam = new ArrayList<BasicNameValuePair>();
				String param = "";
				String value = "";
				while (iterator.hasNext()) {
					param = iterator.next();
					value = params.get(param);
					requestParam.add(new BasicNameValuePair(param, value));
				}
				post.setEntity(new UrlEncodedFormEntity(requestParam, "UTF-8"));
			}
			HttpResponse response = httpClient.execute(post);
			if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
				return null;
			}
			HttpEntity entity = response.getEntity();
			if (entity == null) {
				return null;
			}
			if (entity != null) {
				return EntityUtils.toString(entity, "UTF-8");
			}
		} catch (Exception e) {
			Loger.e("Http Error", e);
		}
		return null;
	}

	/**
	 * 使用 HttpURLConnection Get方法请求网络返回网络流
	 * 
	 * @param urlStr
	 *            请求地址
	 * @return 网络流
	 */
	public static InputStream httpGet(String urlStr) {
		try {
			URL url = new URL(urlStr);
			HttpURLConnection connection = (HttpURLConnection) url.openConnection();
			connection.setRequestProperty("connection", "Keep-Alive");
			connection.setRequestProperty("Charsert", "UTF-8");
			connection.setConnectTimeout(1000 * 20);
			connection.setReadTimeout(1000 * 20);
			connection.setRequestMethod("GET");
			if (connection.getResponseCode() != HttpStatus.SC_OK) {
				return null;
			}
			InputStream inStream = connection.getInputStream();
			if (inStream != null) {
				return inStream;
			}
		} catch (Exception e) {
			Loger.e("HttpGet error", e);
			return null;
		}
		return null;
	}
}