java使用RSA加密方式实现数据加密解密的代码

public static void main(String args[]) {  try {    RSADemo rsa=new RSADemo();    rsa.generateKey();    byte[] data=rsa.encrypt("luanpeng".getBytes());    byte[] data1=rsa.decrypt(data);    String str=new String(data1);    System.out.println(str);  } catch (Exception e) {    System.out.println(e.toString());  }}

package com.lp.app.safe;import java.security.*;import java.security.interfaces.*;import java.math.*;public class RSADemo {  public RSADemo() {  }  PublicKey pbkey;  PrivateKey prkey;  public void generateKey() {    try {      KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");      kpg.initialize(1024);      KeyPair kp = kpg.genKeyPair();      pbkey = kp.getPublic();      prkey = kp.getPrivate();    } catch (Exception e) {    }  }  //加密，需要公钥  public byte[] encrypt(byte[] ptext) throws Exception {    // 获取公钥及参数e,n    RSAPublicKey pbk = (RSAPublicKey)pbkey;    BigInteger e = pbk.getPublicExponent();    BigInteger n = pbk.getModulus();    // 获取明文m    BigInteger m = new BigInteger(ptext);    // 计算密文c    BigInteger c = m.modPow(e, n);    return c.toByteArray();  }  //使用私钥进行解密  public byte[] decrypt(byte[] ctext) throws Exception {    // 读取密文    BigInteger c = new BigInteger(ctext);    // 读取私钥    RSAPrivateKey prk = (RSAPrivateKey)prkey;    BigInteger d = prk.getPrivateExponent();    // 获取私钥参数及解密    BigInteger n = prk.getModulus();    BigInteger m = c.modPow(d, n);    // 显示解密结果    byte[] mt = m.toByteArray();    return mt;  }}