三种加密方式,java版本实现代码如下：

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;


import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;


public class EncodeTest {


	private String encodeMd5(String src) {
		MessageDigest messageDigest = null;
		try {
			messageDigest = MessageDigest.getInstance("MD5");
			messageDigest.reset();
			messageDigest.update(src.getBytes("utf-8"));
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		byte[] byteArray = messageDigest.digest();
		return fromBytesToHex(byteArray);


	}


	private String encodeDes(String src, String password) throws Exception {
		SecretKey secretKey = new SecretKeySpec(password.getBytes(), "DES");


		Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
		cipher.init(Cipher.ENCRYPT_MODE, secretKey);
		byte[] dist = cipher.doFinal(src.getBytes("utf-8"));
		return fromBytesToHex(dist);
	}


	public static byte[] initKey() throws NoSuchAlgorithmException {
		KeyGenerator keyGen = KeyGenerator.getInstance("AES");
		keyGen.init(128);
		SecretKey secretKey = keyGen.generateKey();
		return secretKey.getEncoded();
	}


	public String encodeAes(String src, byte[] key) throws Exception {
		SecretKey secretKey = new SecretKeySpec(key, "AES");
		Cipher cipher = Cipher.getInstance("AES");
		cipher.init(Cipher.ENCRYPT_MODE, secretKey);
		byte[] cipherBytes = cipher.doFinal(src.getBytes());
		return fromBytesToHex(cipherBytes);
	}


	public static String fromBytesToHex(byte[] resultBytes) {
		StringBuilder builder = new StringBuilder();
		for (int i = 0; i < resultBytes.length; i++) {
			if (Integer.toHexString(0xFF & resultBytes[i]).length() == 1) {
				builder.append("0").append(
						Integer.toHexString(0xFF & resultBytes[i]));
			} else {
				builder.append(Integer.toHexString(0xFF & resultBytes[i]));
			}
		}
		return builder.toString();
	}


	public static void main(String[] args) throws Exception {
		EncodeTest et = new EncodeTest();
		String password = "helloword";
		String result = et.encodeMd5(password);
		System.out.println(result);
		System.out.println(et.encodeDes(password, "Bye-2016"));
		byte[] aesKey = et.initKey();
		System.out.println(et.encodeAes(password, aesKey));
	}
}

运行结果

59284aa85709ddaf3bd246030060f6a2
049db4281b51b198bb26fffbb040fde1
c6693135b2179504ad3d59ac930fb278

DES/AES解密基本上替换DECRYPT_MODE即可