将服务器端证书和客户端证书保存到本地，客户端证书在D:\download\client.p12，服务器端证书在D:\download\server.cer(本例使用的服务器端证书和客户端证书是使用keytool自创建的，方法见另一篇博客

https://mp.csdn.net/console/editor/html/105595647)

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStream;

import java.security.KeyStore;

import javax.net.ssl.SSLContext;

import org.apache.http.HttpEntity;

import org.apache.http.client.methods.CloseableHttpResponse;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.conn.ssl.SSLConnectionSocketFactory;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.ssl.SSLContexts;

import org.apache.http.util.EntityUtils;

public class HttpsDemo {

private final static String PFX_PATH = "D:\\download\\client.p12"; //客户端证书路径

private final static String PFX_PWD = "123456"; //客户端证书密码

public static String sslRequestGet(String url) throws Exception {

KeyStore keyStore = KeyStore.getInstance("PKCS12");

File file = new File(PFX_PATH);

InputStream instream = new FileInputStream(file);

try {

keyStore.load(instream, PFX_PWD.toCharArray());

} finally {

instream.close();

}

SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore, PFX_PWD.toCharArray()).build();

SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext,

new String[] {"TLSv1", "TLSv1.1", "TLSv1.2"},

null,

SSLConnectionSocketFactory.getDefaultHostnameVerifier());

CloseableHttpClient httpclient = HttpClients.custom().setSSLSocketFactory(sslsf).build();

try {

HttpGet httpget = new HttpGet(url);

// httpost.addHeader("Connection", "keep-alive");// 设置一些heander等

CloseableHttpResponse response = httpclient.execute(httpget);

try {

HttpEntity entity = response.getEntity();

String jsonStr = EntityUtils.toString(response.getEntity(), "UTF-8");//返回结果

EntityUtils.consume(entity);

return jsonStr;

} finally {

response.close();

}

} finally {

httpclient.close();

}

}

public static void main(String[] args) throws Exception {

System.out.println(System.getProperty("java.home"));

String context = sslRequestGet("https://sntest.zlyd.com/");

System.out.println(context);

// System.out.println(sslRequestGet("https://sntest.zlyd.com:443/"));

}

}

在运行前，要先做一些准备工作：

启动服务器端tomcat，打开你需要访问的端口(如： iptables -I INPUT -p tcp --dport 443 -j ACCEPT)

运行，可能会抛出异常

PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path

解决方法：

进入 %JAVA_HOME%/jre/lib/security 目录下，运行命令行：

keytool -import -alias server -keystore cacerts -file D:\download\server.cer

回车，输入cacerts证书库的密码：changeit

【查看cacerts证书库：keytool -list -keystore cacerts

删除cacerts证书库中某个证书：keytool -delete -alias akazam_email -keystore cacerts】

重新运行java程序