Java封装http请求

import org.apache.http.*;
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.params.CoreConnectionPNames;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.CharArrayBuffer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class HttpUtil {
    private HttpUtil() {
        throw new AssertionError("Utility classes are not meant to be instantiated.");
    }

    /**
     * 常量 log.
     */
    private static final Logger logger = LoggerFactory.getLogger(HttpUtil.class);



    public static void main(String[] args) {
        
    }

    public static String http(String url, Map<String, String> paramMap) {
        DefaultHttpClient client = new DefaultHttpClient();
        try {
            List<BasicNameValuePair> nameValuePairs = new ArrayList<BasicNameValuePair>();
            nameValuePairs.add(new BasicNameValuePair("r", String.valueOf(Math.random())));
            if (paramMap != null) {
                for (Map.Entry entry : paramMap.entrySet()) {
                    nameValuePairs.add(new BasicNameValuePair(entry.getKey().toString(), entry.getValue().toString()));
                }
            }

            HttpPost post = new HttpPost(url);

            post.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 5000);// 请求超时
            post.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 6000);// 读取超时

            post.setEntity(new UrlEncodedFormEntity(new ArrayList(nameValuePairs), HTTP.UTF_8));

            HttpProtocolParams.setUseExpectContinue(client.getParams(), false);

            HttpResponse response = client.execute(post);
            if (response.getStatusLine().getStatusCode() == 200) {// 如果状态码为200,就是正常返回
                String ret = toString(response.getEntity());
                return ret;
            }
        } catch (Exception e) {
            logger.error("http异常", e);
        } finally {
            client.getConnectionManager().shutdown();
        }
        return null;
    }

    public static String getContentCharSet(HttpEntity entity) throws ParseException {
        if (entity == null) {
            throw new IllegalArgumentException("HTTP entity may not be null");
        }
        String charset = null;
        if (entity.getContentType() != null) {
            HeaderElement[] values = entity.getContentType().getElements();
            if (values.length > 0) {
                NameValuePair param = values[0].getParameterByName("charset");
                if (param != null) {
                    charset = param.getValue();
                }
            }
        }
        return charset;
    }

    public static String toString(HttpEntity entity) throws IOException, ParseException {
        return toString(entity, null);
    }

    public static String toString(HttpEntity entity, String defaultCharset) throws IOException, ParseException {
        if (entity == null) {
            throw new IllegalArgumentException("HTTP entity may not be null");
        }
        InputStream instream = entity.getContent();
        if (instream == null) {
            return null;
        }
        try {
            if (entity.getContentLength() > 2147483647L) {
                throw new IllegalArgumentException("HTTP entity too large to be buffered in memory");
            }
            int i = (int) entity.getContentLength();
            if (i < 0) {
                i = 4096;
            }
            String charset = getContentCharSet(entity);
            if (charset == null) {
                charset = defaultCharset;
            }
            if (charset == null) {
                charset = "UTF-8";
            }
            Reader reader = new InputStreamReader(instream, charset);
            CharArrayBuffer buffer = new CharArrayBuffer(i);
            char[] tmp = new char['?'];
            int l;
            while ((l = reader.read(tmp)) != -1) {
                buffer.append(tmp, 0, l);
            }
            return buffer.toString();
        } finally {
            instream.close();
        }
    }

    /**
     * 发送GET请求
     *
     * @param url
     *            目的地址
     * @param parameters
     *            请求参数，Map类型。
     * @return 远程响应结果
     */
    public static String sendGet(String url, Map<String, String> parameters) {
        String result="";
        BufferedReader in = null;// 读取响应输入流
        StringBuffer sb = new StringBuffer();// 存储参数
        String params = "";// 编码之后的参数
        try {
            // 编码请求参数
            if(parameters!=null){
                if(parameters.size()==1){
                    for(String name:parameters.keySet()){
                        sb.append(name).append("=").append(
                                java.net.URLEncoder.encode(parameters.get(name),
                                        "UTF-8"));
                    }
                    params=sb.toString();
                }else{
                    for (String name : parameters.keySet()) {
                        sb.append(name).append("=").append(
                                java.net.URLEncoder.encode(parameters.get(name),
                                        "UTF-8")).append("&");
                    }
                    String temp_params = sb.toString();
                    params = temp_params.substring(0, temp_params.length() - 1);
                }
            }
            String full_url = url + "?" + params;
            // System.out.println(full_url);
            // 创建URL对象
            java.net.URL connURL = new java.net.URL(full_url);
            // 打开URL连接
            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL
                    .openConnection();
            // 设置通用属性
            httpConn.setRequestProperty("Accept", "*/*");
            httpConn.setRequestProperty("Connection", "Keep-Alive");
            httpConn.setRequestProperty("User-Agent",
                    "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
            // 建立实际的连接
            httpConn.connect();
            // 响应头部获取
            Map<String, List<String>> headers = httpConn.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : headers.keySet()) {
                //System.out.println(key + "\t：\t" + headers.get(key));
            }
            // 定义BufferedReader输入流来读取URL的响应,并设置编码方式
            in = new BufferedReader(new InputStreamReader(httpConn
                    .getInputStream(), "UTF-8"));
            String line;
            // 读取返回的内容
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            try {
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return result ;
    }
    /**
     * 发送POST请求
     *
     * @param url
     *            目的地址
     * @param parameters
     *            请求参数，Map类型。
     * @return 远程响应结果
     */
    public static String sendPost(String url, Map<String, String> parameters) {
        String result = "";// 返回的结果
        BufferedReader in = null;// 读取响应输入流
        PrintWriter out = null;
        StringBuffer sb = new StringBuffer();// 处理请求参数
        String params = "";// 编码之后的参数
        try {
            // 编码请求参数
            if(parameters!=null){
                if (parameters.size() == 1) {
                    for (String name : parameters.keySet()) {
                        sb.append(name).append("=").append(
                                java.net.URLEncoder.encode(parameters.get(name),
                                        "UTF-8"));
                    }
                    params = sb.toString();
                } else {
                    for (String name : parameters.keySet()) {
                        sb.append(name).append("=").append(
                                java.net.URLEncoder.encode(parameters.get(name),
                                        "UTF-8")).append("&");
                    }
                    String temp_params = sb.toString();
                    params = temp_params.substring(0, temp_params.length() - 1);
                }
            }
            // 创建URL对象
            java.net.URL connURL = new java.net.URL(url);
            // 打开URL连接
            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL
                    .openConnection();
            // 设置通用属性
            httpConn.setRequestProperty("Accept", "*/*");
            httpConn.setRequestProperty("Connection", "Keep-Alive");
            httpConn.setRequestProperty("User-Agent",
                    "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
            // 设置POST方式
            httpConn.setDoInput(true);
            httpConn.setDoOutput(true);
            // 获取HttpURLConnection对象对应的输出流
            out = new PrintWriter(httpConn.getOutputStream());
            // 发送请求参数
            out.write(params);
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应，设置编码方式
            in = new BufferedReader(new InputStreamReader(httpConn
                    .getInputStream(), "UTF-8"));
            String line;
            // 读取返回的内容
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return result;
    }


}