在文件中读取私钥和公钥

在做项目中，碰到是给到定的私钥和公钥，我们得把公钥和私钥读出来才可以使用，私钥一般还会有密码！

	/**
	 * 获取公钥
	 */
	public PublicKey readPublicKey(String cerFileName) {

		CertificateFactory cf;
		FileInputStream in;
		Certificate c;
		PublicKey pk = null;
		try {
			cf = CertificateFactory.getInstance("X.509");
			in = new FileInputStream(cerFileName);
			c = cf.generateCertificate(in);
			pk = c.getPublicKey();

		} catch (CertificateException e) {
			log.error("获取公钥错误！！！");
			log.error(e.getMessage());
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			log.error("获取公钥错误！！！");
			log.error(e.getMessage());
			e.printStackTrace();
		}
		return pk;
	}

	/**
	 * 获取私钥
	 * 
	 * @return
	 */
	public PrivateKey readPrivateKey(String privateKeyFileName,
			String privatepass) {

		KeyStore ks;
		PrivateKey prk = null;
		try {
			ks = KeyStore.getInstance("pkcs12");
			FileInputStream fis = new FileInputStream(privateKeyFileName);
			ks.load(fis, null);
			String pwd = privatepass;
			String alias = ks.aliases().nextElement().toString();
			prk = (PrivateKey) ks.getKey(alias, pwd.toCharArray());
		} catch (Exception e) {
			log.error("获取私钥错误！！！");
			log.error(e.getMessage());
			e.printStackTrace();
		}

		return prk;
	}