Apache HttpClient访问网络工具类

package com.ztravel.utils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
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;

public class HttpClientUtils {

    public static String sendHttpclientPost(String path,
            Map<String, String> map, String encode) {
        // TODO Auto-generated method stub
        // 填充表单的内容
        List<NameValuePair> pairs = new ArrayList<NameValuePair>();
        // Key必须与action接收params的key一致
        if (map != null && !map.isEmpty()) {
            // 一个entry代表一个键值对，.getKey()获取键，getValue()获取值
            for (Map.Entry<String, String> entry : map.entrySet()) {
                pairs.add(new BasicNameValuePair(entry.getKey(), entry
                        .getValue()));
            }
        }
        try {
            // 添加form表单的内容，和网页的jsp一样
            UrlEncodedFormEntity entity = new UrlEncodedFormEntity(pairs,
                    encode);
            // 使用post提交数据
            HttpPost httpPost = new HttpPost(path);
            httpPost.setEntity(entity);
            HttpClient httpClient = new DefaultHttpClient();
            // HttpResponse获得服务器响应的所有消息
            HttpResponse response = httpClient.execute(httpPost);
            // 判断连接成功
            if (response.getStatusLine().getStatusCode() == 200) {
                // HttpEntity获得服务器响应回来的消息体(不包括HTTP HEAD)
                HttpEntity httpEntity = response.getEntity();
                // 自动分辨响应的内容的编码
                String defaultCharset = EntityUtils
                        .getContentCharSet(httpEntity);
                // EntityUtils.toString将获得的消息体转换成String
                return EntityUtils.toString(httpEntity, defaultCharset);
            }
        } catch (ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // 因为结果经常调用string的函数，所以没有返回null
        return "";

    }

    public static String sendHttpclientGet(HttpClient httpClient, String path) {

        try {// 利用HTTPGET 向服务器发起请求
                // 如果URL连接过程中302重定向，则会自动跳转到新的页面
            HttpGet get = new HttpGet(path);

            // HttpResponse获得服务器响应的所有消息
            HttpResponse response = httpClient.execute(get);

            // HttpEntity获得服务器响应回来的消息体(不包括HTTP HEAD)
            HttpEntity httpEntity = response.getEntity();

            if (httpEntity != null) {// 获取消息体的内容
                String defaultCharset = EntityUtils
                        .getContentCharSet(httpEntity);
                // EntityUtils.toString将获得的消息体转换成String
                return EntityUtils.toString(httpEntity, defaultCharset);
            }

        } catch (Exception e) {
        }
        return "";// 返回"",但不是空值
    }

    /**
     * 从网络获取图片字节数组
     * @param path
     * @return
     */
    public static byte[] getByteArrayByUrl(String path) {
        byte[] data = null;
        try {// 利用HTTPGET 向服务器发起请求
                // 如果URL连接过程中302重定向，则会自动跳转到新的页面
            HttpGet get = new HttpGet(path);

            HttpClient httpClient=new DefaultHttpClient();;
            // HttpResponse获得服务器响应的所有消息
            HttpResponse response = httpClient.execute(get);

            // HttpEntity获得服务器响应回来的消息体(不包括HTTP HEAD)
            HttpEntity httpEntity = response.getEntity();

            if (httpEntity != null) {// 获取消息体的内容
                data = EntityUtils.toByteArray(httpEntity);
            }

        } catch (Exception e) {
        }
        return data;// 返回"",但不是空值
    }
}