最近做小程式使用者ID驗證的問題，文明傳遞有風險，所以想加密再傳送使用者ID，找了些加密的方法，

最開始想用MD5加密，以前有過這樣的加密方式，現在換一種RES方式   對應的一組公鑰和私鑰加密方式，

/**
* @author lmc
* @version date：2018年9月27日 上午11:08:27
*/

package com.yitai.tms.weixin.rsa;

import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;

import org.apache.commons.codec.binary.Hex;


/**
 * @author lmc
 * @Email 
 
[email protected]
 * @date 2018年9月27日
 */
public class RSAwechat {
	
    private RSAPublicKey rsaPublicKey;
    private RSAPrivateKey rsaPrivateKey;

    public String encode(String src)
    {
        try
        {
            //初始化金鑰
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
            keyPairGenerator.initialize(512);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            rsaPublicKey = (RSAPublicKey)keyPair.getPublic();
            rsaPrivateKey = (RSAPrivateKey)keyPair.getPrivate();

            //私鑰加密 公鑰解密
            PKCS8EncodedKeySpec pkcs8EncodedKeySpec 
                = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] resultBytes = cipher.doFinal(src.getBytes());

            //私鑰解密 公鑰加密
//          X509EncodedKeySpec x509EncodedKeySpec =
//                  new X509EncodedKeySpec(rsaPublicKey.getEncoded());
//          KeyFactory keyFactory = KeyFactory.getInstance("RSA");
//          PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
//          Cipher cipher = Cipher.getInstance("RSA");
//          cipher.init(Cipher.ENCRYPT_MODE, publicKey);
//          byte[] resultBytes = cipher.doFinal(src.getBytes());

            return Hex.encodeHexString(resultBytes);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

        return null;
    }

    public String decode(String src)
    {
        try
        {
            //私鑰加密 公鑰解密
            X509EncodedKeySpec x509EncodedKeySpec =
                    new X509EncodedKeySpec(rsaPublicKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            byte[] resultBytes = cipher.doFinal(Hex.decodeHex(src.toCharArray()));

            //私鑰解密 公鑰加密
//          PKCS8EncodedKeySpec pkcs8EncodedKeySpec 
//              = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
//          KeyFactory keyFactory = KeyFactory.getInstance("RSA");
//          PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
//          Cipher cipher = Cipher.getInstance("RSA");
//          cipher.init(Cipher.DECRYPT_MODE, privateKey);
//          byte[] resultBytes = cipher.doFinal(Hex.decodeHex(src.toCharArray()));

            return new String(resultBytes);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }
	
}
 

加密方式

/**
* @author lmc
* @version date：2018年9月27日 上午11:11:11
*/

package com.yitai.tms.weixin.rsa;

/**
 * @author lmc
 * @Email [email protected]
 * @date 2018年9月27日
 */
public class RSAtool {

	
	private static 	RSAwechat rsa=new RSAwechat();
	public static String encRSAwechat(String token){
		return rsa.encode(token);
	}
	
	public static String decRSAwechat(String token){
		return rsa.decode(token);
	}
	
	public static void main(String args[]) 
	{
		System.out.println(RSAtool.encRSAwechat("asdfasdfasdfa"));
		String str = RSAtool.encRSAwechat("asdfasdfasdfa");
		System.out.println(RSAtool.decRSAwechat(str));
	}


}