RSA非对称加密解密

import org.apache.commons.codec.binary.Base64;

import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;

/**
* Created by zxf on 2016/9/22.
*/
public class Rsa {
public static final String KEY_ALGORITHM = "RSA";
/** 由于Android与服务器的的问题这里必须是:RSA/NONE/PKCS1Padding，未验证 */
public static final String CIPHER_ALGORITHM = "RSA/NONE/PKCS1Padding";
public static final String PUBLIC_KEY = "MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAIRdil4gf0xCBbWWhLdXLcBNcDAxm131ZbrrA7p6kz3HKT3GqfoVQCwbgZ9JyvW/KhmNI4I2+PGX+Nbg1rLyDE0CAwEAAQ==";
//public static final String PRIVATE_KEY = "privateKey";
public static final String PRIVATE_KEY = "MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAhF2KXiB/TEIFtZaEt1ctwE1wMDGbXfVluusDunqTPccpPcap+hVALBuBn0nK9b8qGY0jgjb48Zf41uDWsvIMTQIDAQABAkBQXTKbP4PKWvN4crCVV/rRHLMWr6ey/kELoZCb8bvf71uEFLgk7Q9GEvM6F4ucH9Mp8qexJUBEWwGpmolkO4GJAiEA6nGVJ970KEjTYd4RuEJ0zrTilQZ0Q52Yk/kvtIiZFqMCIQCQiTQRQoJVBvL74tzbW++vFdPw4gadOs7BKTkjGYywTwIgTrBy/N/zmXXgJVAxKGR96keCabyx12QVK02POoxCvfsCIAhVkQYJwsAqZWp222tessRyysTSE7WPRYrH2L6YY49rAiEAxREH2PCWeA4Q4eh2JnpRFS3w2pdrvYUlT/97FG3oXlI=";

/** RSA密钥长度必须是64的倍数，在512~65536之间。默认是1024 */
public static final int KEY_SIZE = 1024;

public static final String PLAIN_TEXT = "lamboo";

public static void main(String[] args) {
// 加密
PublicKey publicKey = restorePublicKey(Base64.decodeBase64(PUBLIC_KEY));
byte[] encodedText = RSAEncode(publicKey, PLAIN_TEXT.getBytes());
System.out.println("RSA encoded: " + Base64.encodeBase64String(encodedText));

// 解密

PrivateKey privateKey = restorePrivateKey(Base64.decodeBase64(PRIVATE_KEY));
System.out.println("RSA decoded: "+ RSADecode(privateKey, encodedText));
}

/**
* 还原公钥，X509EncodedKeySpec 用于构建公钥的规范
*
* @param keyBytes
* @return
*/
public static PublicKey restorePublicKey(byte[] keyBytes) {
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);

try {
KeyFactory factory = KeyFactory.getInstance(KEY_ALGORITHM);
PublicKey publicKey = factory.generatePublic(x509EncodedKeySpec);
return publicKey;
} catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
// TO
4000
DO Auto-generated catch block
e.printStackTrace();
}
return null;
}

/**
* 还原私钥，PKCS8EncodedKeySpec 用于构建私钥的规范
*
* @param keyBytes
* @return
*/
public static PrivateKey restorePrivateKey(byte[] keyBytes) {
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(
keyBytes);
try {
KeyFactory factory = KeyFactory.getInstance(KEY_ALGORITHM);
PrivateKey privateKey = factory
.generatePrivate(pkcs8EncodedKeySpec);
return privateKey;
} catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}

/**
* 加密，三步走。
*
* @param key
* @param plainText
* @return
*/
public static byte[] RSAEncode(PublicKey key, byte[] plainText) {

try {
Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, key);
return cipher.doFinal(plainText);
} catch (NoSuchAlgorithmException | NoSuchPaddingException
| InvalidKeyException | IllegalBlockSizeException
| BadPaddingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;

}

/**
* 解密，三步走。
*
* @param key
* @param encodedText
* @return
*/
public static String RSADecode(PrivateKey key, byte[] encodedText) {

try {
Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, key);
return new String(cipher.doFinal(encodedText));
} catch (NoSuchAlgorithmException | NoSuchPaddingException
| InvalidKeyException | IllegalBlockSizeException
| BadPaddingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;

}
}