java jdk原生的http请求工具类

 package com.base;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.Reader;
 import java.net.HttpURLConnection;
 import java.net.SocketTimeoutException;
 import java.net.URL;
 import java.net.URLEncoder;
 import java.security.SecureRandom;
 import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
 import java.util.Map;
 import java.util.Set;

 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.HttpsURLConnection;
 import javax.net.ssl.KeyManager;
 import javax.net.ssl.SSLContext;
 import javax.net.ssl.SSLSession;
 import javax.net.ssl.TrustManager;
 import javax.net.ssl.X509TrustManager;

 /**
  *
  * @ClassName:  HttpUtils
  * @Description:http请求工具类
  * @author: zhouyy
  * @date:   2019年10月14日 下午3:50:34
  *
  */
 public class HttpUtils {
     private static final String CTYPE_FORM = "application/x-www-form-urlencoded;charset=utf-8";
     private static final String CTYPE_JSON = "application/json; charset=utf-8";
     private static final String charset = "utf-8";

     private static HttpUtils instance = null;

     public static HttpUtils getInstance() {
         if (instance == null) {
             return new HttpUtils();
         }
         return instance;
     }

     public static void main(String[] args) throws SocketTimeoutException, IOException {
         String resp = getInstance().postJson("http://localhost:8080/test/test", "{\"custCmonId\":\"12345678\",\"custNo\":\"111\",\"custNo111\":\"706923\"}");
         System.out.println(resp);
     }

     private class DefaultTrustManager implements X509TrustManager {
         public X509Certificate[] getAcceptedIssuers() {
             return null;
         }

         public void checkClientTrusted(X509Certificate[] chain, String authType)
                 throws CertificateException {
         }

         public void checkServerTrusted(X509Certificate[] chain, String authType)
                 throws CertificateException {
         }
     }

     /**
      * 以application/json; charset=utf-8方式传输
      *
      * @param url
      * @param requestContent
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      */
     public String postJson(String url, String jsonContent)
             throws SocketTimeoutException, IOException {
         return doRequest("POST", url, jsonContent, 15000, 15000, CTYPE_JSON,
                 null);
     }

     /**
      * POST 以application/x-www-form-urlencoded;charset=utf-8方式传输
      *
      * @param url
      * @param requestContent
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      */
     public String postForm(String url) throws SocketTimeoutException,
             IOException {
         return doRequest("POST", url, "", 15000, 15000, CTYPE_FORM, null);
     }

     /**
      * POST 以application/x-www-form-urlencoded;charset=utf-8方式传输
      *
      * @param url
      * @param requestContent
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      */
     public String postForm(String url, Map<String, String> params)
             throws SocketTimeoutException, IOException {
         return doRequest("POST", url, buildQuery(params), 15000, 15000,
                 CTYPE_FORM, null);
     }

     /**
      * POST 以application/x-www-form-urlencoded;charset=utf-8方式传输
      *
      * @param url
      * @param requestContent
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      */
     public String getForm(String url) throws SocketTimeoutException,
             IOException {
         return doRequest("GET", url, "", 15000, 15000, CTYPE_FORM, null);
     }

     /**
      * POST 以application/x-www-form-urlencoded;charset=utf-8方式传输
      *
      * @param url
      * @param requestContent
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      */
     public String getForm(String url, Map<String, String> params)
             throws SocketTimeoutException, IOException {
         return doRequest("GET", url, buildQuery(params), 15000, 15000,
                 CTYPE_FORM, null);
     }

     /**
      *
      * <p>@Description: </p>
      * @Title doRequest
      * @author zhouyy
      * @param method 请求的method post/get
      * @param url 请求url
      * @param requestContent  请求参数
      * @param connectTimeout  请求超时
      * @param readTimeout 响应超时
      * @param ctype 请求格式  xml/json等等
      * @param headerMap 请求header中要封装的参数
      * @return
      * @throws SocketTimeoutException
      * @throws IOException
      * @date: 2019年10月14日 下午3:47:35
      */
     private String doRequest(String method, String url, String requestContent,
             int connectTimeout, int readTimeout, String ctype,
             Map<String, String> headerMap) throws SocketTimeoutException,
             IOException {
         HttpURLConnection conn = null;
         OutputStream out = null;
         String rsp = null;
         try {
             conn = getConnection(new URL(url), method, ctype, headerMap);
             conn.setConnectTimeout(connectTimeout);
             conn.setReadTimeout(readTimeout);

             if(requestContent != null && requestContent.trim().length() >0){
                 out = conn.getOutputStream();
                 out.write(requestContent.getBytes(charset));
             }

             rsp = getResponseAsString(conn);
         } finally {
             if (out != null) {
                 out.close();
             }
             if (conn != null) {
                 conn.disconnect();
             }
             conn = null;
         }
         return rsp;
     }

     private HttpURLConnection getConnection(URL url, String method,
             String ctype, Map<String, String> headerMap) throws IOException {
         HttpURLConnection conn;
         if ("https".equals(url.getProtocol())) {
             SSLContext ctx;
             try {
                 ctx = SSLContext.getInstance("TLS");
                 ctx.init(new KeyManager[0],
                         new TrustManager[] { new DefaultTrustManager() },
                         new SecureRandom());
             } catch (Exception e) {
                 throw new IOException(e);
             }
             HttpsURLConnection connHttps = (HttpsURLConnection) url
                     .openConnection();
             connHttps.setSSLSocketFactory(ctx.getSocketFactory());
             connHttps.setHostnameVerifier(new HostnameVerifier() {
                 public boolean verify(String hostname, SSLSession session) {
                     return true;
                 }
             });
             conn = connHttps;
         } else {
             conn = (HttpURLConnection) url.openConnection();
         }
         conn.setRequestMethod(method);
         conn.setDoInput(true);
         conn.setDoOutput(true);
         conn.setRequestProperty("Accept",
                 "text/xml,text/javascript,text/html,application/json");
         conn.setRequestProperty("Content-Type", ctype);
         if (headerMap != null) {
             for (Map.Entry<String, String> entry : headerMap.entrySet()) {
                 conn.setRequestProperty(entry.getKey(), entry.getValue());
             }
         }
         return conn;
     }

     private String getResponseAsString(HttpURLConnection conn)
             throws IOException {
         InputStream es = conn.getErrorStream();
         if (es == null) {
             return getStreamAsString(conn.getInputStream(), charset, conn);
         } else {
             String msg = getStreamAsString(es, charset, conn);
             if (msg != null && msg.trim().length() >0) {
                 throw new IOException(conn.getResponseCode() + ":"
                         + conn.getResponseMessage());
             } else {
                 return msg;
             }
         }
     }

     private String getStreamAsString(InputStream stream, String charset,
             HttpURLConnection conn) throws IOException {
         try {
             Reader reader = new InputStreamReader(stream, charset);

             StringBuilder response = new StringBuilder();
             final char[] buff = new char[1024];
             int read = 0;
             while ((read = reader.read(buff)) > 0) {
                 response.append(buff, 0, read);
             }

             return response.toString();
         } finally {
             if (stream != null) {
                 stream.close();
             }
         }
     }

     private String buildQuery(Map<String, String> params) throws IOException {
         if (params == null || params.isEmpty()) {
             return "";
         }

         StringBuilder query = new StringBuilder();
         Set<Map.Entry<String, String>> entries = params.entrySet();
         boolean hasParam = false;

         for (Map.Entry<String, String> entry : entries) {
             String name = entry.getKey();
             String value = entry.getValue();
             if (hasParam) {
                 query.append("&");
             } else {
                 hasParam = true;
             }
             query.append(name).append("=")
                     .append(URLEncoder.encode(value, charset));
         }
         return query.toString();
     }
 }

非原著，借鉴大神！

https://www.cnblogs.com/jpfss/p/10063666.html