RSA加密

import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;

import javax.crypto.Cipher;

/**
* RSAEncrypt
*
* @author maqujun
* @see
*/
public class RSAEncrypt {

/**
* Main method for RSAEncrypt.
* @param args
*/
public static void main(String[] args) {
try {
RSAEncrypt encrypt = new RSAEncrypt();

String encryptText = "encryptText";
KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");
keyPairGen.initialize(1024);
KeyPair keyPair = keyPairGen.generateKeyPair();
// Generate keys
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();

byte[] e = encrypt.encrypt(publicKey, encryptText.getBytes());
byte[] de = encrypt.decrypt(privateKey,e);
System.out.println(encrypt.bytesToString(e));
System.out.println(encrypt.bytesToString(de));
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* Change byte array to String.
* @return byte[]
*/
protected String bytesToString(byte[] encrytpByte) {
String result = "";
for (Byte bytes : encrytpByte) {
result += (char) bytes.intValue();
}
return result;
}

/**
* Encrypt String.
* @return byte[]
*/
protected byte[] encrypt(RSAPublicKey publicKey, byte[] obj) {
if (publicKey != null) {
try {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(obj);
} catch (Exception e) {
e.printStackTrace();
}
}
return null;
}

/**
* Basic decrypt method
* @return byte[]
*/
protected byte[] decrypt(RSAPrivateKey privateKey, byte[] obj) {
if (privateKey != null) {
try {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(obj);
} catch (Exception e) {
e.printStackTrace();
}
}

return null;
}
}