证书工具类

证书工具类：

import java.io.FileInputStream;
import java.io.StringWriter;
import java.io.Writer;
import java.security.Key;
import java.security.KeyPair;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;

import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManagerFactory;

import org.bouncycastle.openssl.PEMWriter;

/**
 * 证书操作工具类
 */
public class CaUtils {

	public static final String KEY_STORE = "JKS";

	public static final String X509 = "X.509";

	public static final String SunX509 = "SunX509";

	public static final String SSL = "SSL";

	/**
	 * 获取KeyStore
	 * @param keyStorePath
	 * @param password
	 * @return KeyStore
	 * @throws Exception
	 */
	public static KeyStore getKeyStore(String keyStorePath,String password)throws Exception
	{
		FileInputStream fis = new FileInputStream(keyStorePath);
		KeyStore ks = KeyStore.getInstance(KEY_STORE);
		ks.load(fis, password.toCharArray());
		fis.close();
		return ks;
	}

	/**
	 * 获取Certificate
	 * @param certificatePath
	 * @return Certificate
	 * @throws Exception
	 */
	public static Certificate getCertificate(String certificatePath)throws Exception
	{
		CertificateFactory certificateFactory = CertificateFactory.getInstance(X509);
		FileInputStream fis = new FileInputStream(certificatePath);
		Certificate certificate = certificateFactory.generateCertificate(fis);
		fis.close();
		return certificate;
	}

	/**
	 * 获取私钥
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return PrivateKey
	 * @throws Exception
	 */
	public static PrivateKey getPrivateKey(String keyStorePath,String alias,String password)throws Exception
	{
		KeyStore ks = getKeyStore(keyStorePath, password);
		PrivateKey privateKey = (PrivateKey) ks.getKey(alias, password.toCharArray());
		return privateKey;
	}

	/**
	 * 获取公钥
	 * @param certificatePath
	 * @return PublicKey
	 * @throws Exception
	 */
	public static PublicKey getPublicKey(String certificatePath)throws Exception
	{
		Certificate certificate = getCertificate(certificatePath);
		PublicKey publicKey = certificate.getPublicKey();
		return publicKey;
	}

	/**
	 * 获取公钥
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return PublicKey
	 * @throws Exception
	 */
	public static PublicKey getPublicKey(String keyStorePath,String alias,String password)throws Exception
	{
		KeyStore ks = getKeyStore(keyStorePath, password);
		Certificate cert = ks.getCertificate(alias);
		PublicKey publicKey = cert.getPublicKey();
		return publicKey;
	}

	/**
	 * Key转换为Pem格式
	 * @param Key
	 * @return 字符串(Pem格式)
	 * @throws Exception
	 */
	public static String changeKeyToPem(Key key)throws Exception
	{
		PEMWriter pemWriter;
		try {
			Writer writer = new StringWriter();
			pemWriter = new PEMWriter(writer);
			pemWriter.writeObject(key);
			pemWriter.flush();
			pemWriter.close();
			return writer.toString();
		} finally {
			pemWriter = null;
		}
	}

	/**
	 * 获得SSLSocketFactory
	 * @param password
	 * @param keyStorePath
	 * @param trustKeyStorePath
	 * @return SSLSocketFactory
	 * @throws Exception
	 */
	public static SSLSocketFactory getSSLSocketFactory(String password,String keyStorePath, String trustKeyStorePath) throws Exception
	{
		// 初始化密钥库
		KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(SunX509);
		KeyStore keyStore = getKeyStore(keyStorePath, password);
		keyManagerFactory.init(keyStore, password.toCharArray());
		// 初始化信任库
		TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(SunX509);
		KeyStore trustkeyStore = getKeyStore(trustKeyStorePath, password);
		trustManagerFactory.init(trustkeyStore);
		// 初始化SSL上下文
		SSLContext ctx = SSLContext.getInstance(SSL);
		ctx.init(keyManagerFactory.getKeyManagers(), trustManagerFactory.getTrustManagers(), null);
		SSLSocketFactory sf = ctx.getSocketFactory();
		return sf;
	}

	/**
	 * 获取密钥对
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return KeyPair
	 * @throws Exception
	 */
	public static KeyPair getKeyPair(String keyStorePath,String alias,String password)throws Exception
	{
		KeyStore ks = getKeyStore(keyStorePath, password);
		Key key = ks.getKey(alias, password.toCharArray());
		if (key instanceof PrivateKey)
        {
			Certificate cert = ks.getCertificate(alias);
            PublicKey publicKey = cert.getPublicKey();
            return new KeyPair(publicKey, (PrivateKey) key);
        }else
        {
        	return null;
        }
	}

}