java实现https请求

HttpsUtil.java

package com.lichmama.test.util;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.URL;

import java.security.KeyManagementException;

import java.security.NoSuchAlgorithmException;

import java.security.SecureRandom;

import java.security.cert.CertificateException;

import java.security.cert.X509Certificate;

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.SSLSocketFactory;

import javax.net.ssl.TrustManager;

import javax.net.ssl.X509TrustManager;

public class HttpsUtil {

    private static final class DefaultTrustManager implements X509TrustManager {

        @Override

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

        }

        @Override

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

        }

        @Override

        public X509Certificate[] getAcceptedIssuers() {

            return null;

        }

    }

    private static HttpsURLConnection getHttpsURLConnection(String uri, String method) throws IOException {

        SSLContext ctx = null;

        try {

            ctx = SSLContext.getInstance("TLS");

            ctx.init(new KeyManager[0], new TrustManager[] { new DefaultTrustManager() }, new SecureRandom());

        } catch (KeyManagementException e) {

            e.printStackTrace();

        } catch (NoSuchAlgorithmException e) {

            e.printStackTrace();

        }

        SSLSocketFactory ssf = ctx.getSocketFactory();

        URL url = new URL(uri);

        HttpsURLConnection httpsConn = (HttpsURLConnection) url.openConnection();

        httpsConn.setSSLSocketFactory(ssf);

        httpsConn.setHostnameVerifier(new HostnameVerifier() {

            @Override

            public boolean verify(String arg0, SSLSession arg1) {

                return true;

            }

        });

        httpsConn.setRequestMethod(method);

        httpsConn.setDoInput(true);

        httpsConn.setDoOutput(true);

        return httpsConn;

    }

    private static byte[] getBytesFromStream(InputStream is) throws IOException {

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        byte[] kb = new byte[1024];

        int len;

        while ((len = is.read(kb)) != -1) {

            baos.write(kb, 0, len);

        }

        byte[] bytes = baos.toByteArray();

        baos.close();

        is.close();

        return bytes;

    }

    private static void setBytesToStream(OutputStream os, byte[] bytes) throws IOException {

        ByteArrayInputStream bais = new ByteArrayInputStream(bytes);

        byte[] kb = new byte[1024];

        int len;

        while ((len = bais.read(kb)) != -1) {

            os.write(kb, 0, len);

        }

        os.flush();

        os.close();

        bais.close();

    }

    public static byte[] doGet(String uri) throws IOException {

        HttpsURLConnection httpsConn = getHttpsURLConnection(uri, "GET");

        return getBytesFromStream(httpsConn.getInputStream());

    }

    public static byte[] doPost(String uri, String data) throws IOException {

        HttpsURLConnection httpsConn = getHttpsURLConnection(uri, "POST");

        setBytesToStream(httpsConn.getOutputStream(), data.getBytes());

        return getBytesFromStream(httpsConn.getInputStream());

    }

}

下载个文件（bing今日美图）测试下：

public class TestHttps {

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

        String uri = "https://cn.bing.com/hpwp/356677bea977a9aa166a92ab94848f17";

        byte[] bytes = HttpsUtil.doGet(uri);

        FileOutputStream fos = new FileOutputStream("D:/bing.picture-of-day.jpg");

        fos.write(bytes);

        fos.close();

        System.out.println("done!");

    }

}

在weblogic中使用如上代码时，可能会出现ClassCastException，详情及解决方案可查看以下链接：

http://www.th7.cn/Program/java/201511/688262.shtml

http://blog.csdn.net/arvinrong/article/details/7715334