HelloWorld 善戰者,求之于勢,不責于人;故能擇人而任勢。

import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Signature;

public class RsaTest {
 public static void main(String args[]) throws Exception {
  SecureRandom sr = new SecureRandom();
  KeyPairGenerator kg = KeyPairGenerator.getInstance("DSA");
  kg.initialize(512, sr);

  //產生新密鑰對
  KeyPair kp = kg.generateKeyPair();
  //獲得私匙
  PrivateKey prk = kp.getPrivate();
  //獲得公鑰
  PublicKey puk = kp.getPublic();
  //返回一個指定算法的Signature對象
  Signature signature = Signature.getInstance("DSA");
  signature.initSign(prk);
  String str = "你好嗎?我在測試RSA測試^_^你好嗎?我在測試RSA測試^_^你好嗎?我在測試RSA測試^_^你好嗎?我在測試RSA測試^_^";
  signature.update(str.getBytes());
  byte[] dest = signature.sign();
  System.out.println("Enc:"+new String(dest));
  
  Signature signature2 = Signature.getInstance("DSA");
  signature2.initVerify(puk);
  signature2.update(str.getBytes());
  System.out.println(signature2.verify(dest));
 }
}

</script>