摘要：解決的問題問題描述這兩天上測試服務器的時候突然報這樣的異常問題的根本訪問的時候缺少安全證書，導致的錯誤解決措施將安全證書下載到本地。輸入等待程序執行完成，當前目錄下會生成一個的安全文件將證書拷貝到目錄下重新啟動完成

這兩天上測試服務器的時候突然報這樣的異常javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

訪問https的時候缺少安全證書，導致的錯誤

將安全證書下載到本地 =.= 。查閱了很久的資料，找到如下一份大神的源碼特來分享

/*
 * Copyright 2006 Sun Microsystems, Inc.  All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.security.KeyStore;
import java.security.MessageDigest;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
 
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;
 
public class InstallCert {
 
    public static void main(String[] args) throws Exception {
        String host;
        int port;
        char[] passphrase;
        if ((args.length == 1) || (args.length == 2)) {
            String[] c = args[0].split(":");
            host = c[0];
            port = (c.length == 1) ? 443 : Integer.parseInt(c[1]);
            String p = (args.length == 1) ? "changeit" : args[1];
            passphrase = p.toCharArray();
        } else {
            System.out
                    .println("Usage: java InstallCert [:port] [passphrase]");
            return;
        }
 
        File file = new File("jssecacerts");
        if (file.isFile() == false) {
            char SEP = File.separatorChar;
            File dir = new File(System.getProperty("java.home") + SEP + "lib"
                    + SEP + "security");
            file = new File(dir, "jssecacerts");
            if (file.isFile() == false) {
                file = new File(dir, "cacerts");
            }
        }
        System.out.println("Loading KeyStore " + file + "...");
        InputStream in = new FileInputStream(file);
        KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
        ks.load(in, passphrase);
        in.close();
 
        SSLContext context = SSLContext.getInstance("TLS");
        TrustManagerFactory tmf = TrustManagerFactory
                .getInstance(TrustManagerFactory.getDefaultAlgorithm());
        tmf.init(ks);
        X509TrustManager defaultTrustManager = (X509TrustManager) tmf
                .getTrustManagers()[0];
        SavingTrustManager tm = new SavingTrustManager(defaultTrustManager);
        context.init(null, new TrustManager[] { tm }, null);
        SSLSocketFactory factory = context.getSocketFactory();
 
        System.out
                .println("Opening connection to " + host + ":" + port + "...");
        SSLSocket socket = (SSLSocket) factory.createSocket(host, port);
        socket.setSoTimeout(10000);
        try {
            System.out.println("Starting SSL handshake...");
            socket.startHandshake();
            socket.close();
            System.out.println();
            System.out.println("No errors, certificate is already trusted");
        } catch (SSLException e) {
            System.out.println();
            e.printStackTrace(System.out);
        }
 
        X509Certificate[] chain = tm.chain;
        if (chain == null) {
            System.out.println("Could not obtain server certificate chain");
            return;
        }
 
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                System.in));
 
        System.out.println();
        System.out.println("Server sent " + chain.length + " certificate(s):");
        System.out.println();
        MessageDigest sha1 = MessageDigest.getInstance("SHA1");
        MessageDigest md5 = MessageDigest.getInstance("MD5");
        for (int i = 0; i < chain.length; i++) {
            X509Certificate cert = chain[i];
            System.out.println(" " + (i + 1) + " Subject "
                    + cert.getSubjectDN());
            System.out.println("   Issuer  " + cert.getIssuerDN());
            sha1.update(cert.getEncoded());
            System.out.println("   sha1    " + toHexString(sha1.digest()));
            md5.update(cert.getEncoded());
            System.out.println("   md5     " + toHexString(md5.digest()));
            System.out.println();
        }
 
        System.out
                .println("Enter certificate to add to trusted keystore or "q" to quit: [1]");
        String line = reader.readLine().trim();
        int k;
        try {
            k = (line.length() == 0) ? 0 : Integer.parseInt(line) - 1;
        } catch (NumberFormatException e) {
            System.out.println("KeyStore not changed");
            return;
        }
 
        X509Certificate cert = chain[k];
        String alias = host + "-" + (k + 1);
        ks.setCertificateEntry(alias, cert);
 
        OutputStream out = new FileOutputStream("jssecacerts");
        ks.store(out, passphrase);
        out.close();
 
        System.out.println();
        System.out.println(cert);
        System.out.println();
        System.out
                .println("Added certificate to keystore "jssecacerts" using alias ""
                        + alias + """);
    }
 
    private static final char[] HEXDIGITS = "0123456789abcdef".toCharArray();
 
    private static String toHexString(byte[] bytes) {
        StringBuilder sb = new StringBuilder(bytes.length * 3);
        for (int b : bytes) {
            b &= 0xff;
            sb.append(HEXDIGITS[b >> 4]);
            sb.append(HEXDIGITS[b & 15]);
            sb.append(" ");
        }
        return sb.toString();
    }
 
    private static class SavingTrustManager implements X509TrustManager {
 
        private final X509TrustManager tm;
        private X509Certificate[] chain;
 
        SavingTrustManager(X509TrustManager tm) {
            this.tm = tm;
        }
 
        public X509Certificate[] getAcceptedIssuers() {
            throw new UnsupportedOperationException();
        }
 
        public void checkClientTrusted(X509Certificate[] chain, String authType)
                throws CertificateException {
            throw new UnsupportedOperationException();
        }
 
        public void checkServerTrusted(X509Certificate[] chain, String authType)
                throws CertificateException {
            this.chain = chain;
            tm.checkServerTrusted(chain, authType);
        }
    }
}

1.首先將java文件編譯成class文件，使用javac命令 javac InstallCert.java
2.當前目錄下即產生InstallCert.class文件以及InstallCert$SavingTrustManager.class文件
3.運行InstallCert.class文件并傳入參數，java InstallCert host:port 通過作者的源碼可以得知默認端口為443

此時會輸出如下信息

G:com>java InstallCert www.baidu.com
Loading KeyStore C:Program FilesJavajre1.8.0_191libsecuritycacerts...
Opening connection to www.baidu.com:443...
Starting SSL handshake...

javax.net.ssl.SSLException: java.lang.UnsupportedOperationException
        at sun.security.ssl.Alerts.getSSLException(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.fatal(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.fatal(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.handleException(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
        at InstallCert.main(InstallCert.java:95)
Caused by: java.lang.UnsupportedOperationException
        at InstallCert$SavingTrustManager.getAcceptedIssuers(InstallCert.java:18
0)
        at sun.security.ssl.AbstractTrustManagerWrapper.checkAlgorithmConstraint
s(Unknown Source)
        at sun.security.ssl.AbstractTrustManagerWrapper.checkAdditionalTrust(Unk
nown Source)
        at sun.security.ssl.AbstractTrustManagerWrapper.checkServerTrusted(Unkno
wn Source)
        at sun.security.ssl.ClientHandshaker.serverCertificate(Unknown Source)
        at sun.security.ssl.ClientHandshaker.processMessage(Unknown Source)
        at sun.security.ssl.Handshaker.processLoop(Unknown Source)
        at sun.security.ssl.Handshaker.process_record(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source
)
        ... 3 more

Server sent 2 certificate(s):

 1 Subject CN=baidu.com, O="Beijing Baidu Netcom Science Technology Co., Ltd", O
U=service operation department, L=beijing, ST=beijing, C=CN
   Issuer  CN=GlobalSign Organization Validation CA - SHA256 - G2, O=GlobalSign
nv-sa, C=BE
   sha1    d6 aa f8 cf a0 e0 23 65 47 fc 2a 89 4f 89 5e c9 47 24 a6 0d
   md5     fd 63 96 dc 4e 9f 1e a9 16 51 d6 87 73 4d 39 76

 2 Subject CN=GlobalSign Organization Validation CA - SHA256 - G2, O=GlobalSign
nv-sa, C=BE
   Issuer  CN=GlobalSign Root CA, OU=Root CA, O=GlobalSign nv-sa, C=BE
   sha1    90 2e f2 de eb 3c 5b 13 ea 4c 3d 51 93 62 93 09 e2 31 ae 55
   md5     d3 e8 70 6d 82 92 ac e4 dd eb f7 a8 bb bd 56 6b

Enter certificate to add to trusted keystore or "q" to quit: [1]

4.輸入q為退出，輸入1為下載。輸入1等待程序執行完成，當前目錄下會生成一個jssecacerts的安全文件
5.將證書拷貝到$JAVA_HOME/jre/lib/security目錄下
6.重新啟動web server

完成~