就我而言，我有一个pem文件，其中包含两个证书和一个用于相互SSL身份验证的加密私钥。所以我的pem文件看起来像这样：
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: DES-EDE3-CBC,C8BF220FC76AA5F9
...
-----END RSA PRIVATE KEY-----
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
这是我所做的：
将文件分为三个单独的文件，以便每个文件仅包含一个条目，以“ --- BEGIN ..”开头，以“ --- END ..”结尾。假设我们现在有三个文件：cert1.pem cert2.pem和pkey.pem
使用openssl和以下语法将pkey.pem转换为DER格式：
openssl pkcs8 -topk8 -nocrypt -in pkey.pem -inform PEM -out pkey.der -outform DER
请注意，如果私钥已加密，则需要提供密码（从原始pem文件的供应商处获取）以转换为DER格式，openssl会要求您输入密码，例如：“为pkey输入密码.pem：“如果转换成功，您将获得一个名为” pkey.der“的新文件。
创建一个新的Java密钥库，并导入私钥和证书：
String keypass = "password"; // this is a new password, you need to come up with to protect your java key store file
String defaultalias = "importkey";
KeyStore ks = KeyStore.getInstance("JKS", "SUN");
// this section does not make much sense to me,
// but I will leave it intact as this is how it was in the original example I found on internet:
ks.load( null, keypass.toCharArray());
ks.store( new FileOutputStream ( "mykeystore" ), keypass.toCharArray());
ks.load( new FileInputStream ( "mykeystore" ), keypass.toCharArray());
// end of section..
// read the key file from disk and create a PrivateKey
FileInputStream fis = new FileInputStream("pkey.der");
DataInputStream dis = new DataInputStream(fis);
byte[] bytes = new byte[dis.available()];
dis.readFully(bytes);
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
byte[] key = new byte[bais.available()];
KeyFactory kf = KeyFactory.getInstance("RSA");
bais.read(key, 0, bais.available());
bais.close();
PKCS8EncodedKeySpec keysp = new PKCS8EncodedKeySpec ( key );
PrivateKey ff = kf.generatePrivate (keysp);
// read the certificates from the files and load them into the key store:
Collection col_crt1 = CertificateFactory.getInstance("X509").generateCertificates(new FileInputStream("cert1.pem"));
Collection col_crt2 = CertificateFactory.getInstance("X509").generateCertificates(new FileInputStream("cert2.pem"));
Certificate crt1 = (Certificate) col_crt1.iterator().next();
Certificate crt2 = (Certificate) col_crt2.iterator().next();
Certificate[] chain = new Certificate[] { crt1, crt2 };
String alias1 = ((X509Certificate) crt1).getSubjectX500Principal().getName();
String alias2 = ((X509Certificate) crt2).getSubjectX500Principal().getName();
ks.setCertificateEntry(alias1, crt1);
ks.setCertificateEntry(alias2, crt2);
// store the private key
ks.setKeyEntry(defaultalias, ff, keypass.toCharArray(), chain );
// save the key store to a file
ks.store(new FileOutputStream ( "mykeystore" ),keypass.toCharArray());
（可选）验证新密钥库的内容：
keytool -list -keystore mykeystore -storepass password
密钥库类型：JKS密钥库提供者：SUN
您的密钥库包含3个条目
cn = ...，ou = ...，o = ..，2014年9月2日，trustCertEntry，证书指纹（SHA1）：2C：B8：...
importkey，2014年9月2日，PrivateKeyEntry，证书指纹（SHA1）：9C：B0：...
cn = ...，o = ....，2014年9月2日，trustCertEntry，证书指纹（SHA1）：83:63：...
（可选）针对SSL服务器测试新密钥存储中的证书和私钥：（您可能希望将调试作为VM选项启用：-Djavax.net.debug = all）
char[] passw = "password".toCharArray();
KeyStore ks = KeyStore.getInstance("JKS", "SUN");
ks.load(new FileInputStream ( "mykeystore" ), passw );
KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
kmf.init(ks, passw);
TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
tmf.init(ks);
TrustManager[] tm = tmf.getTrustManagers();
SSLContext sclx = SSLContext.getInstance("TLS");
sclx.init( kmf.getKeyManagers(), tm, null);
SSLSocketFactory factory = sclx.getSocketFactory();
SSLSocket socket = (SSLSocket) factory.createSocket( "192.168.1.111", 443 );
socket.startHandshake();
//if no exceptions are thrown in the startHandshake method, then everything is fine..
如果打算使用它，最后向HttpsURLConnection注册您的证书：
char[] passw = "password".toCharArray();
KeyStore ks = KeyStore.getInstance("JKS", "SUN");
ks.load(new FileInputStream ( "mykeystore" ), passw );
KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
kmf.init(ks, passw);
TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
tmf.init(ks);
TrustManager[] tm = tmf.getTrustManagers();
SSLContext sclx = SSLContext.getInstance("TLS");
sclx.init( kmf.getKeyManagers(), tm, null);
HostnameVerifier hv = new HostnameVerifier()
{
public boolean verify(String urlHostName, SSLSession session)
{
if (!urlHostName.equalsIgnoreCase(session.getPeerHost()))
{
System.out.println("Warning: URL host '" + urlHostName + "' is different to SSLSession host '" + session.getPeerHost() + "'.");
}
return true;
}
};
HttpsURLConnection.setDefaultSSLSocketFactory( sclx.getSocketFactory() );
HttpsURLConnection.setDefaultHostnameVerifier(hv);