testrsa.java

常用的java控件使用实例源代码

import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import javax.crypto.Cipher;

public class testRSA {
	public static void main(String[] agrs ) {
		try {
			testRSA ept = new testRSA();
			String encryptText = "my information";
			KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("rsa");
			keyPairGen.initialize(1024);
			KeyPair KeyPair = keyPairGen.generateKeyPair();
			RSAPrivateKey PrivateKey = (RSAPrivateKey) KeyPair.getPrivate();
			RSAPublicKey PublicKey = (RSAPublicKey) KeyPair.getPublic();
			
			byte[] e = ept.encrypt(PublicKey,encryptText.getBytes());//使用公钥加密过程
			byte[] de = ept.decrypt(PrivateKey,e);//解密过程用自己的私钥
			String str = "";
			str = ept.bytesToString(e);
			System.out.println(str);
			System.out.println(ept.bytesToString(de));
				
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	protected String bytesToString(byte[] encryptByte) {
		String result = "";
		for( Byte bytes : encryptByte) {
			result += (char) bytes.intValue();
		}
		return result;
	}
	
	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;
	}
	
	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;
	}
	
}