Java生成非对称型加密的公钥和私钥

import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;

/**
 * RSA非对称型加密的公钥和私钥
 * @author 五斗米 <如转载请保留作者和出处>
 * @blog http://blog.csdn.net/mq612
 */

public class KeyRSA {
  private KeyPairGenerator kpg = null;
  private KeyPair kp = null;
  private PublicKey public_key = null;
  private PrivateKey private_key = null;
  private FileOutputStream public_file_out = null;
  private ObjectOutputStream public_object_out = null;
  private FileOutputStream private_file_out = null;
  private ObjectOutputStream private_object_out = null;

  /**
   * 构造函数
   * @param in 指定密匙长度（取值范围：512～2048）
   * @throws NoSuchAlgorithmException 异常
   */
  public KeyRSA(int in,String address) throws NoSuchAlgorithmException,FileNotFoundException,IOException {
    kpg = KeyPairGenerator.getInstance("RSA"); //创建‘密匙对’生成器
    kpg.initialize(in); //指定密匙长度（取值范围：512～2048）
    kp = kpg.genKeyPair(); //生成‘密匙对’，其中包含着一个公匙和一个私匙的信息
    public_key = kp.getPublic(); //获得公匙
    private_key = kp.getPrivate(); //获得私匙
    //保存公匙
    public_file_out = new FileOutputStream(address + "/public_key.dat");
    public_object_out = new ObjectOutputStream(public_file_out);
    public_object_out.writeObject(public_key);
    //保存私匙
    private_file_out = new FileOutputStream(address + "/private_key.dat");
    private_object_out = new ObjectOutputStream(private_file_out);
    private_object_out.writeObject(private_key);
  }

  public static void main(String[] args) {
    try {
      new KeyRSA(1024,"c:/key_rsa");
    }
    catch (IOException ex) {
    }
    catch (NoSuchAlgorithmException ex) {
    }
  }

}