Java生成RSA非对称型加密的公钥和私钥(利用java API)

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

/**//**
* <p>Title: RSA非对称型加密的公钥和私钥</p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2003</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

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 ...{
          System.out.println("私匙和公匙保存到C盘下的文件中.");
      new KeyRSA(1024, "c:/");
    }
    catch (IOException ex) ...{
    }
    catch (NoSuchAlgorithmException ex) ...{
    }
  }

}