在我的例子中，我遇到了这个问题，因为在我的tomcat进程中，特定的密钥存储库是使用的

-Djavax.net.ssl.trustStore=/pathtosomeselfsignedstore/truststore.jks

当我将证书导入JRE/lib/security的cacert时，没有反映更改。 然后执行以下命令，其中/tmp/cert1。Test包含目标服务器的证书

keytool -import -trustcacerts -keystore /pathtosomeselfsignedstore/truststore.jks -storepass password123 -noprompt -alias rapidssl-myserver -file /tmp/cert1.test

可以再次检查证书导入是否成功

keytool -list -v -keystore /pathtosomeselfsignedstore/truststore.jks

并查看是否在别名rapidssl-myserver中找到您的taget服务器

eclipse / Sts用户注意:

因为eclipse使用它自己的JRE，您应该将cert添加到它自己的JRE密钥存储库中。 我有这个问题，直到我添加certs到圣的JRE。

SSL日志:

`javax.net.ssl|DEBUG|1A|restartedMain|2021-12-06 23:04:00.874` IRST|TrustStoreManager.java:113|trustStore is: D:\sts-4.12.0.RELEASE\plugins\org.eclipse.justj.openjdk.hotspot.jre.full.win32.x86_64_16.0.2.v20210721-1149\jre\lib\security\cacerts
This is the full path: "sts-4.12.0.RELEASE\plugins\org.eclipse.justj.openjdk.hotspot.jre.full.win32.x86_64_16.0.2.v20210721-1149\jre\lib\security\cacerts"

I had the same problem with sbt. It tried to fetch dependencies from repo1.maven.org over ssl but said it was "unable to find valid certification path to requested target url". so I followed this post and still failed to verify a connection. So I read about it and found that the root cert is not enough, as was suggested by the post,so - the thing that worked for me was importing the intermediate CA certificates into the keystore. I actually added all the certificates in the chain and it worked like a charm.

这里是解决方案，按照下面的链接一步一步:

http://www.mkyong.com/webservices/jax-ws/suncertpathbuilderexception-unable-to-find-valid-certification-path-to-requested-target/

JAVA文件:博客中缺少的文件

/*
 * 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.*;
import java.net.URL;

import java.security.*;
import java.security.cert.*;

import javax.net.ssl.*;

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 <host>[: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);
    }
    }

}

我在试图从我的应用程序访问https url时遇到了这个错误，该应用程序正在使用自签名证书。 他们提供的是一个.cert文件，我不知道该把它放在哪里。我是这样解决的:

keytool的位置在JDK/bin文件夹下

方法1:将证书添加到默认的Java信任库- cacerts:

keytool -import -alias myCert -file C://certificate.cert -keystore C://Program Files//Java//jdk1.8.0_271//jre//lib//security//cacerts

密码:changeit

方法2:

创建信任存储:

keytool -import -alias myCert -file C://certificate.cert -keystore myTrustStore

它会给你以下提示，可以填充为:

Enter keystore password:changeit
Re-enter new password:changeit
Trust this certificate?yes

这将在运行此命令的文件夹中创建一个myTrustStore文件。 将这个“mytrustStore”复制到一个方便的位置。

使用信任存储:

当你运行你的应用程序/服务器时，传递这些JVM参数:

-Djavax.net.ssl.trustStore=C://myTrustStore -Djavax.net.ssl.trustStorePassword=changeit

在我的情况下，我得到错误连接到AWS Gov Postgres RDS。GOV RDS CA证书有一个单独的链接- https://s3.us-gov-west-1.amazonaws.com/rds-downloads/rds-combined-ca-us-gov-bundle.pem

将此pem certs添加到java的cacerts中。您可以使用下面的脚本。

——WINDOWDS步骤

使用VSCODE编辑器，安装openssl, keytool插件 在C:/rds-ca目录下创建目录 将“cacerts”文件和下面的脚本文件-“addCerts.sh”在目录“rd-ca” 运行vscode: 4.1 CD /c/rds-ca/ . 4.2。/ addCerts.sh 拷贝cacerts到${JAVA_HOME}/jre/lib/security目录下

脚本代码:

#!/usr/bin/env sh

OLDDIR="$PWD"

CACERTS_FILE=cacerts

cd /c/rds-ca

echo "Downloading RDS certificates..."

curl  https://s3.us-gov-west-1.amazonaws.com/rds-downloads/rds-combined-ca-us-gov-bundle.pem > rds-combined-ca-bundle.pem

csplit -sk rds-combined-ca-bundle.pem "/-BEGIN CERTIFICATE-/" "{$(grep -c 'BEGIN CERTIFICATE' rds-combined-ca-bundle.pem | awk '{print $1 - 2}')}"

for CERT in xx*; do
    # extract a human-readable alias from the cert
    ALIAS=$(openssl x509 -noout -text -in $CERT |
                   perl -ne 'next unless /Subject:/; s/.*CN=//; print')
    echo "importing $ALIAS"
    
    keytool -import \
            -keystore  $CACERTS_FILE \
            -storepass changeit -noprompt \
            -alias "$ALIAS" -file $CERT
done

cd "$OLDDIR"
echo "$NEWDIR"