说明

网站配置https，需要为域名申请证书，例如域名为：www.xxx.com，申请的证书为：

从上图可以看出，证书除了公钥/私钥，直接为：Nginx、Apache、IIS、Tomcat做好了准备。

Java程序读取

读取.pem、.key、.crt

package com.what21.demo.cert;

import cn.hutool.crypto.PemUtil;
import org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPrivateCrtKey;
import org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPublicKey;

import java.io.FileInputStream;
import java.io.InputStream;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

public class CertKeyUtils {

    /**
     * 读取 .pem 文件
     *
     * @param file
     * @return
     * @throws Exception
     */
    public static BCRSAPublicKey readPemToPublicKey(String file) throws Exception {
        InputStream input = new FileInputStream(file);
        BCRSAPublicKey key = (BCRSAPublicKey) PemUtil.readPemKey(input);
        return key;
    }

    /**
     * 读取 .key 文件
     *
     * @param file
     * @return
     * @throws Exception
     */
    public static BCRSAPrivateCrtKey readKeyToPrivateKey(String file) throws Exception {
        InputStream input = new FileInputStream(file);
        BCRSAPrivateCrtKey key = (BCRSAPrivateCrtKey) PemUtil.readPemPrivateKey(input);
        return key;
    }

    /**
     * 读取 .crt 文件
     *
     * @param file
     * @return
     * @throws Exception
     */
    public static X509Certificate readCrtToPublicKey(String file) throws Exception {
        InputStream input = new FileInputStream(file);
        CertificateFactory cf = CertificateFactory.getInstance("X.509");
        X509Certificate cert = (X509Certificate) cf.generateCertificate(input);
        return cert;
    }

    public static void main(String[] args) throws Exception {
        String pemFile = "D:\\wx\\www.xxx.com\\www.xxx.com.pem";
        System.out.println(readPemToPublicKey(pemFile));
        String keyFile = "D:\\wx\\www.xxx.com\\www.xxx.com.key";
        System.out.println(readKeyToPrivateKey(keyFile));
        String crtFile = "D:\\wx\\www.xxx.com\\Nginx\\1_www.xxx.com_bundle.crt";
        System.out.println(readCrtToPublicKey(crtFile));
    }

}

读取JKS

package com.what21.demo.cert;

import java.io.FileInputStream;
import java.security.KeyPair;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.PublicKey;

public class JksUtils {

    /**
     * @param storePath   秘钥库文件路径
     * @param storePasswd 秘钥库密码
     * @return
     * @throws Exception
     */
    public static KeyStore keyStore(String storePath, String storePasswd)
            throws Exception {
        KeyStore keyStore = KeyStore.getInstance("JKS");
        keyStore.load(new FileInputStream(storePath), storePasswd.toCharArray());
        return keyStore;
    }

    /**
     * @param keyStore    秘钥库
     * @param alias       证书别名
     * @param trustPasswd 证书密码
     * @return
     * @throws Exception
     */
    public static KeyPair keyPair(KeyStore keyStore, String alias, String trustPasswd)
            throws Exception {
        PrivateKey privateKey = (PrivateKey) keyStore.getKey(alias, trustPasswd.toCharArray());
        PublicKey publicKey = keyStore.getCertificate(alias).getPublicKey();
        return new KeyPair(publicKey, privateKey);
    }


    public static void main(String[] args) throws Exception {
        String jksFile = "D:\\wx\\www.xxx.com\\Tomcat\\www.xxx.com.jks";
        String keystorePass = "y696wyxqvsy3i";
        KeyStore keyStore = keyStore(jksFile, keystorePass);
        System.out.println(keyStore);
        // 别名为域名
        String alias = "www.xxx.com";
        // 证书秘钥与秘钥库密码一致
        String trustPasswd = "y696wyxqvsy3i";
        KeyPair keyPair = keyPair(keyStore, alias, trustPasswd);
        System.out.println(keyPair.getPublic());
        System.out.println(keyPair.getPrivate());
    }

}

读取PFX

package com.what21.demo.cert;

import java.io.FileInputStream;
import java.security.KeyPair;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.PublicKey;

public class PfxUtils {

    /**
     * @param storePath   秘钥库文件路径
     * @param storePasswd 秘钥库密码
     * @return
     * @throws Exception
     */
    public static KeyStore keyStore(String storePath, String storePasswd)
            throws Exception {
        KeyStore keyStore = KeyStore.getInstance("PKCS12");
        keyStore.load(new FileInputStream(storePath), storePasswd.toCharArray());
        return keyStore;
    }

    /**
     * @param keyStore    秘钥库
     * @param alias       证书别名
     * @param trustPasswd 证书密码
     * @return
     * @throws Exception
     */
    public static KeyPair keyPair(KeyStore keyStore, String alias, String trustPasswd)
            throws Exception {
        PrivateKey privateKey = (PrivateKey) keyStore.getKey(alias, trustPasswd.toCharArray());
        PublicKey publicKey = keyStore.getCertificate(alias).getPublicKey();
        return new KeyPair(publicKey, privateKey);
    }


    public static void main(String[] args) throws Exception {
        String pfxFile = "D:\\wx\\www.xxx.com\\IIS\\www.xxx.com.pfx";
        String keystorePass = "y696wyxqvsy3i";
        KeyStore keyStore = keyStore(pfxFile, keystorePass);
        System.out.println(keyStore);
        // 别名为域名
        String alias = "www.xxx.com";
        // 证书秘钥与秘钥库密码一致
        String trustPasswd = "y696wyxqvsy3i";
        KeyPair keyPair = keyPair(keyStore, alias, trustPasswd);
        System.out.println(keyPair.getPublic());
        System.out.println(keyPair.getPrivate());
    }

}