httpclient工具类发起get,post,put,delete请求

package com.fh.util;

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

import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.*;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

public class HttpClientUtils {

public static String doGet(String url, Map<String, String> param) {

    // 创建Httpclient对象
    CloseableHttpClient httpclient = HttpClients.createDefault();

    String resultString = "";
    CloseableHttpResponse response = null;
    try {
        // 创建uri
        URIBuilder builder = new URIBuilder(url);
        if (param != null) {
            for (String key : param.keySet()) {
                builder.addParameter(key, param.get(key));
            }
        }
        URI uri = builder.build();

        // 创建http GET请求
        HttpGet httpGet = new HttpGet(uri);

        // 执行请求
        response = httpclient.execute(httpGet);
        // 判断返回状态是否为200
        if (response.getStatusLine().getStatusCode() == 200) {
            resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (response != null) {
                response.close();
            }
            httpclient.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return resultString;
}

public static String doGet(String url) {
    return doGet(url, null);
}

public static String doPost(String url, Map<String, String> param) {
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();
    CloseableHttpResponse response = null;
    String resultString = "";
    try {
        // 创建Http Post请求
        HttpPost httpPost = new HttpPost(url);
        // 创建参数列表
        if (param != null) {
            List<NameValuePair> paramList = new ArrayList<NameValuePair>();
            for (String key : param.keySet()) {
                paramList.add(new BasicNameValuePair(key, param.get(key)));
            }
            // 模拟表单
            UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList, "UTF-8");
            httpPost.setEntity(entity);
        }
        // 执行http请求
        response = httpClient.execute(httpPost);
        resultString = EntityUtils.toString(response.getEntity(), "utf-8");
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            response.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    return resultString;
}
public static String doPost(String url) {
    return doPost(url, null);
}

public static String doPostJson(String url, String json) {
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();
    CloseableHttpResponse response = null;
    String resultString = "";
    try {
        // 创建Http Post请求
        HttpPost httpPost = new HttpPost(url);
        // 创建请求内容
        StringEntity entity = new StringEntity(json, ContentType.APPLICATION_JSON);
        httpPost.setEntity(entity);
        // 执行http请求
        response = httpClient.execute(httpPost);
        resultString = EntityUtils.toString(response.getEntity(), "utf-8");
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            response.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    return resultString;
}

public static String doDelete(String url, Map<String, String> param) {
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();
    CloseableHttpResponse response = null;
    String resultString = "";
    try {
        // 创建Http Delete请求
        HttpDelete httpDelete = new HttpDelete(url);
        // 创建参数列表
        URIBuilder builder = new URIBuilder(url);
        if (param != null) {
            for (String key : param.keySet()) {
                builder.addParameter(key, param.get(key));
            }
        }
        URI uri = builder.build();
        httpDelete.setURI(uri);
        response = httpClient.execute(httpDelete);
        // 判断返回状态是否为200
        if (response.getStatusLine().getStatusCode() == 200) {
            resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            response.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    return resultString;
}

/**
 *功能描述 (发送put请求带参数)
 * @author qqg
 * @date
 * @param  * @param url
 * @param param
 * @return
 */
public static String doPut(String url, Map<String, String> param) {

    // 创建Httpclient对象
    CloseableHttpClient httpclient = HttpClients.createDefault();

    String resultString = "";
    CloseableHttpResponse response = null;
    try {
        // 创建uri
        URIBuilder builder = new URIBuilder(url);
        if (param != null) {
            for (String key : param.keySet()) {
                builder.addParameter(key, param.get(key));
            }
        }
        URI uri = builder.build();

        // 创建http PUT请求
        HttpPut httpPut = new HttpPut(uri);

        // 执行请求
        response = httpclient.execute(httpPut);
        // 判断返回状态是否为200
        if (response.getStatusLine().getStatusCode() == 200) {
            resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (response != null) {
                response.close();
            }
            httpclient.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return resultString;
}

}