HttpClient 发送 HTTP、HTTPS 请求的简单封装

序

近期这几周。一直在忙同一个项目。刚開始是了解需求。需求有一定了解之后，就開始调第三方的接口。因为第三方给提供的文档非常模糊，在调接口的时候，出了非常多问题，一直在沟通协调，详细的无奈就不说了，因为接口的訪问协议是通过 HTTP 和 HTTPS 通讯的，因此封装了一个简单的请求工具类。因为时间紧迫。并没有额外的时间对工具类进行优化和扩展。假设兴许空出时间的话，我会对该工具类继续进行优化和扩展的。

引用

首先说一下该类中须要引入的 jar 包，apache 的 httpclient 包，版本为 4.5，如有须要的话。可以引一下。

代码

<span style="font-family:Comic Sans MS;">import org.apache.commons.io.IOUtils;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLContextBuilder;
import org.apache.http.conn.ssl.TrustStrategy;
import org.apache.http.conn.ssl.X509HostnameVerifier;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocket;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.security.GeneralSecurityException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * HTTP 请求工具类
 *
 * @author : liii
 * @version : 1.0.0
 * @date : 2015/7/21
 * @see : TODO
 */
public class HttpUtil {
    private static PoolingHttpClientConnectionManager connMgr;
    private static RequestConfig requestConfig;
    private static final int MAX_TIMEOUT = 7000;

    static {
        // 设置连接池
        connMgr = new PoolingHttpClientConnectionManager();
        // 设置连接池大小
        connMgr.setMaxTotal(100);
        connMgr.setDefaultMaxPerRoute(connMgr.getMaxTotal());

        RequestConfig.Builder configBuilder = RequestConfig.custom();
        // 设置连接超时
        configBuilder.setConnectTimeout(MAX_TIMEOUT);
        // 设置读取超时
        configBuilder.setSocketTimeout(MAX_TIMEOUT);
        // 设置从连接池获取连接实例的超时
        configBuilder.setConnectionRequestTimeout(MAX_TIMEOUT);
        // 在提交请求之前 測试连接是否可用
        configBuilder.setStaleConnectionCheckEnabled(true);
        requestConfig = configBuilder.build();
    }

    /**
     * 发送 GET 请求（HTTP）。不带输入数据
     * @param url
     * @return
     */
    public static String doGet(String url) {
        return doGet(url, new HashMap<String, Object>());
    }

    /**
     * 发送 GET 请求（HTTP）。K-V形式
     * @param url
     * @param params
     * @return
     */
    public static String doGet(String url, Map<String, Object> params) {
        String apiUrl = url;
        StringBuffer param = new StringBuffer();
        int i = 0;
        for (String key : params.keySet()) {
            if (i == 0)
                param.append("?");
            else
                param.append("&");
            param.append(key).append("=").append(params.get(key));
            i++;
        }
        apiUrl += param;
        String result = null;
        HttpClient httpclient = new DefaultHttpClient();
        try {
            HttpGet httpPost = new HttpGet(apiUrl);
            HttpResponse response = httpclient.execute(httpPost);
            int statusCode = response.getStatusLine().getStatusCode();

            System.out.println("运行状态码 : " + statusCode);

            HttpEntity entity = response.getEntity();
            if (entity != null) {
                InputStream instream = entity.getContent();
                result = IOUtils.toString(instream, "UTF-8");
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 发送 POST 请求（HTTP），不带输入数据
     * @param apiUrl
     * @return
     */
    public static String doPost(String apiUrl) {
        return doPost(apiUrl, new HashMap<String, Object>());
    }

    /**
     * 发送 POST 请求（HTTP），K-V形式
     * @param apiUrl API接口URL
     * @param params 參数map
     * @return
     */
    public static String doPost(String apiUrl, Map<String, Object> params) {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        String httpStr = null;
        HttpPost httpPost = new HttpPost(apiUrl);
        CloseableHttpResponse response = null;

        try {
            httpPost.setConfig(requestConfig);
            List<NameValuePair> pairList = new ArrayList<>(params.size());
            for (Map.Entry<String, Object> entry : params.entrySet()) {
                NameValuePair pair = new BasicNameValuePair(entry.getKey(), entry
                        .getValue().toString());
                pairList.add(pair);
            }
            httpPost.setEntity(new UrlEncodedFormEntity(pairList, Charset.forName("UTF-8")));
            response = httpClient.execute(httpPost);
            System.out.println(response.toString());
            HttpEntity entity = response.getEntity();
            httpStr = EntityUtils.toString(entity, "UTF-8");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (response != null) {
                try {
                    EntityUtils.consume(response.getEntity());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return httpStr;
    }

    /**
     * 发送 POST 请求（HTTP），JSON形式
     * @param apiUrl
     * @param json json对象
     * @return
     */
    public static String doPost(String apiUrl, Object json) {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        String httpStr = null;
        HttpPost httpPost = new HttpPost(apiUrl);
        CloseableHttpResponse response = null;

        try {
            httpPost.setConfig(requestConfig);
            StringEntity stringEntity = new StringEntity(json.toString(),"UTF-8");//解决中文乱码问题
            stringEntity.setContentEncoding("UTF-8");
            stringEntity.setContentType("application/json");
            httpPost.setEntity(stringEntity);
            response = httpClient.execute(httpPost);
            HttpEntity entity = response.getEntity();
            System.out.println(response.getStatusLine().getStatusCode());
            httpStr = EntityUtils.toString(entity, "UTF-8");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (response != null) {
                try {
                    EntityUtils.consume(response.getEntity());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return httpStr;
    }

    /**
     * 发送 SSL POST 请求（HTTPS），K-V形式
     * @param apiUrl API接口URL
     * @param params 參数map
     * @return
     */
    public static String doPostSSL(String apiUrl, Map<String, Object> params) {
        CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(createSSLConnSocketFactory()).setConnectionManager(connMgr).setDefaultRequestConfig(requestConfig).build();
        HttpPost httpPost = new HttpPost(apiUrl);
        CloseableHttpResponse response = null;
        String httpStr = null;

        try {
            httpPost.setConfig(requestConfig);
            List<NameValuePair> pairList = new ArrayList<NameValuePair>(params.size());
            for (Map.Entry<String, Object> entry : params.entrySet()) {
                NameValuePair pair = new BasicNameValuePair(entry.getKey(), entry
                        .getValue().toString());
                pairList.add(pair);
            }
            httpPost.setEntity(new UrlEncodedFormEntity(pairList, Charset.forName("utf-8")));
            response = httpClient.execute(httpPost);
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode != HttpStatus.SC_OK) {
                return null;
            }
            HttpEntity entity = response.getEntity();
            if (entity == null) {
                return null;
            }
            httpStr = EntityUtils.toString(entity, "utf-8");
        } catch (Exception e) {
			e.printStackTrace();
        } finally {
            if (response != null) {
                try {
                    EntityUtils.consume(response.getEntity());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return httpStr;
    }

    /**
     * 发送 SSL POST 请求（HTTPS），JSON形式
     * @param apiUrl API接口URL
     * @param json JSON对象
     * @return
     */
    public static String doPostSSL(String apiUrl, Object json) {
        CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(createSSLConnSocketFactory()).setConnectionManager(connMgr).setDefaultRequestConfig(requestConfig).build();
        HttpPost httpPost = new HttpPost(apiUrl);
        CloseableHttpResponse response = null;
        String httpStr = null;

        try {
            httpPost.setConfig(requestConfig);
            StringEntity stringEntity = new StringEntity(json.toString(),"UTF-8");//解决中文乱码问题
            stringEntity.setContentEncoding("UTF-8");
            stringEntity.setContentType("application/json");
            httpPost.setEntity(stringEntity);
            response = httpClient.execute(httpPost);
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode != HttpStatus.SC_OK) {
                return null;
            }
            HttpEntity entity = response.getEntity();
            if (entity == null) {
                return null;
            }
            httpStr = EntityUtils.toString(entity, "utf-8");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (response != null) {
                try {
                    EntityUtils.consume(response.getEntity());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return httpStr;
    }

    /**
     * 创建SSL安全连接
     *
     * @return
     */
    private static SSLConnectionSocketFactory createSSLConnSocketFactory() {
        SSLConnectionSocketFactory sslsf = null;
        try {
            SSLContext sslContext = new SSLContextBuilder().loadTrustMaterial(null, new TrustStrategy() {

                public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
                    return true;
                }
            }).build();
            sslsf = new SSLConnectionSocketFactory(sslContext, new X509HostnameVerifier() {

                @Override
                public boolean verify(String arg0, SSLSession arg1) {
                    return true;
                }

                @Override
                public void verify(String host, SSLSocket ssl) throws IOException {
                }

                @Override
                public void verify(String host, X509Certificate cert) throws SSLException {
                }

                @Override
                public void verify(String host, String[] cns, String[] subjectAlts) throws SSLException {
                }
            });
        } catch (GeneralSecurityException e) {
            e.printStackTrace();
        }
        return sslsf;
    }


    /**
     * 測试方法
     * @param args
     */
    public static void main(String[] args) throws Exception {

    }
}</span>

结束语

工具类封装的比較粗糙。兴许还会继续优化的，假设小伙伴们有更好的选择的话，希望也可以分享出来，大家一起学习。