JAVA公钥加密，私钥解密，该怎么解决

public abstract class RSACoder extends Coder {public static final String KEY_ALGORITHM = "RSA";public static final String SIGNATURE_ALGORITHM = "MD5withRSA";private static final String PUBLIC_KEY = "RSAPublicKey";private static final String PRIVATE_KEY = "RSAPrivateKey";/*** 用私钥对信息生成数字签名* * @param data 加密数据* @param privateKey* 私钥* * @return* @throws Exception*/public static String sign(byte[] data, String privateKey) throws Exception {// 解密由base64编码的私钥byte[] keyBytes = decryptBASE64(privateKey);// 构造PKCS8EncodedKeySpec对象PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);// KEY_ALGORITHM 指定的加密算法KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 取私钥匙对象PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);// 用私钥对信息生成数字签名Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);signature.initSign(priKey);signature.update(data);return encryptBASE64(signature.sign());}/*** 校验数字签名* * @param data* 加密数据* @param publicKey* 公钥* @param sign* 数字签名* * @return 校验成功返回true 失败返回false* @throws Exception* */public static boolean verify(byte[] data, String publicKey, String sign)throws Exception {// 解密由base64编码的公钥byte[] keyBytes = decryptBASE64(publicKey);// 构造X509EncodedKeySpec对象X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);// KEY_ALGORITHM 指定的加密算法KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 取公钥匙对象PublicKey pubKey = keyFactory.generatePublic(keySpec);Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);signature.initVerify(pubKey);signature.update(data);// 验证签名是否正常return signature.verify(decryptBASE64(sign));}/*** 解密
* 用私钥解密* * @param data* @param key* @return* @throws Exception*/public static byte[] decryptByPrivateKey(byte[] data, String key)throws Exception {// 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得私钥PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);// 对数据解密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, privateKey);return cipher.doFinal(data);}/*** 解密
* 用公钥解密* * @param data* @param key* @return* @throws Exception*/public static byte[] decryptByPublicKey(byte[] data, String key)throws Exception {// 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得公钥X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key publicKey = keyFactory.generatePublic(x509KeySpec);// 对数据解密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, publicKey);return cipher.doFinal(data);}/*** 加密
* 用公钥加密* * @param data* @param key* @return* @throws Exception*/public static byte[] encryptByPublicKey(byte[] data, String key)throws Exception {// 对公钥解密byte[] keyBytes = decryptBASE64(key);// 取得公钥X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key publicKey = keyFactory.generatePublic(x509KeySpec);// 对数据加密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, publicKey);return cipher.doFinal(data);}/*** 加密
* 用私钥加密* * @param data* @param key* @return* @throws Exception*/public static byte[] encryptByPrivateKey(byte[] data, String key)throws Exception {// 对密钥解密byte[] keyBytes = decryptBASE64(key);// 取得私钥PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);// 对数据加密Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, privateKey);return cipher.doFinal(data);}/*** 取得私钥* * @param keyMap* @return* @throws Exception*/public static String getPrivateKey(Map keyMap)throws Exception {Key key = (Key) keyMap.get(PRIVATE_KEY);return encryptBASE64(key.getEncoded());}/*** 取得公钥* * @param keyMap* @return* @throws Exception*/public static String getPublicKey(Map keyMap)throws Exception {Key key = (Key) keyMap.get(PUBLIC_KEY);return encryptBASE64(key.getEncoded());}/*** 初始化密钥* * @return* @throws Exception*/public static Map initKey() throws Exception {KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);keyPairGen.initialize(1024);KeyPair keyPair = keyPairGen.generateKeyPair();// 公钥RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();// 私钥RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();Map keyMap = new HashMap(2);keyMap.put(PUBLIC_KEY, publicKey);keyMap.put(PRIVATE_KEY, privateKey);return keyMap;}}