使用java调用http请求系列--HttpURLConnection

简介：该工具类使用HttpURLConnection实现了调用http请求，同时支持调用https请求。

1.实现及测试代码：

import com.lenovo.m2.test.utils.StringUtil;

import javax.net.ssl.*;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.security.SecureRandom;
import java.security.cert.X509Certificate;

/**
 * Created by admin on 2017/9/21.
 * 使用HttpURLConnection调用http接口
 */
public class HttpURLConnectionUtil {
    private static class MyX509TrustManager implements X509TrustManager {

        @Override
        public void checkClientTrusted(X509Certificate[] arg0, String arg1) {
        }

        @Override
        public void checkServerTrusted(X509Certificate[] arg0, String arg1) {
        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }

    }

    /**
     * 该方法为调用https请求方法
     * @param url 请求的url
     * @param requestMethod 请求的方式：GET、POST
     * @param params 请求的参数：key1=value1&key2=value2
     * @return
     */
    public static String requestHttps(String url,String requestMethod,String params){
        HttpsURLConnection connection = null;
        String result = "";
        try {
            // 创建SSLContext对象，并使用我们指定的信任管理器初始化
            TrustManager[] tm = { new MyX509TrustManager() };
            /*TrustManager[] tm = {
                new X509TrustManager() {
                    @Override
                    public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
                    }
                    @Override
                    public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
                    }
                    @Override
                    public X509Certificate[] getAcceptedIssuers() {
                        return null;
                    }
                }
            };*/
            SSLContext sslContext = SSLContext.getInstance("SSL", "SunJSSE");
            sslContext.init(null, tm, new SecureRandom());
            // 从上述SSLContext对象中得到SSLSocketFactory对象
            SSLSocketFactory ssf = sslContext.getSocketFactory();

            URL requestUrl = new URL(url);
            connection = (HttpsURLConnection)requestUrl.openConnection();
            //设置SSL签名
            connection.setSSLSocketFactory(ssf);
            //设置请求方式GET，POST
            connection.setRequestMethod(requestMethod);
            //设置是否使用缓存
            connection.setUseCaches(false);
            connection.setConnectTimeout(100000);
            connection.setReadTimeout(100000);
            if (!StringUtil.isEmpty(params)){
                //如果有参数，将参数写入
                connection.setDoOutput(true);
                connection.getOutputStream().write(params.getBytes("utf-8"));
            }
            InputStream in = connection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(in, "utf-8"));
            String line = null;
            while ((line=reader.readLine())!=null){
                result += line;
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            if (connection!=null){
                connection.disconnect();
            }
        }
        return result;
    }

    /**
     * 该方法为调用http请求方法
     * @param url 请求的url
     * @param requestMethod 请求的方式：GET、POST
     * @param params 请求的参数：key1=value1&key2=value2
     * @return
     */
    public static String requestHttp(String url,String requestMethod,String params){
        HttpURLConnection connection = null;
        String result = "";
        try {
            URL requestUrl = new URL(url);
            connection = (HttpURLConnection)requestUrl.openConnection();
            //设置请求方式GET，POST
            connection.setRequestMethod(requestMethod);
            //设置是否使用缓存
            connection.setUseCaches(false);
            connection.setConnectTimeout(100000);
            connection.setReadTimeout(100000);
            if (!StringUtil.isEmpty(params)){
                //如果有参数，将参数写入
                connection.setDoOutput(true);
                connection.getOutputStream().write(params.getBytes("utf-8"));
            }
            InputStream in = connection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(in, "utf-8"));
            String line = null;
            while ((line=reader.readLine())!=null){
                result += line;
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            if (connection!=null){
                connection.disconnect();
            }
        }
        return result;
    }

    public static void main(String[] args) {
        String requestMethod = "GET";
        System.out.println(requestHttp("http://www.baidu.com",requestMethod,null));
        System.out.println(requestHttps("https://www.baidu.com", requestMethod, null));
    }
}