AES简单加密解密的方法实现

Posted 2020-09-22 雨落秋垣

package com.mstf.aes;
 
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
 
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
 
/**
 * AES加密解密
 * @author ceet
 *
 */
public class AESUntil {
	/**
	 * 加密
	 * 
	 *
	 */
	public static String Ecodes(String content, String key) {
		if (content == null || content.length() < 1)
			return null;
 
		try {
			KeyGenerator kgen = KeyGenerator.getInstance("AES");
			kgen.init(128, new SecureRandom(key.getBytes()));
			SecretKey secretKey = kgen.generateKey();
			byte[] enCodeFormat = secretKey.getEncoded();
			SecretKeySpec secretKeySpec = new SecretKeySpec(enCodeFormat, "AES");
			Cipher cipher = Cipher.getInstance("AES");
			byte[] byteContent = content.getBytes("utf-8");
			cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
			byte[] byteRresult = cipher.doFinal(byteContent);
			StringBuffer sb = new StringBuffer();
			for (int i = 0; i < byteRresult.length; i++) {
				String hex = Integer.toHexString(byteRresult[i] & 0xFF);
				if (hex.length() == 1) {
					hex = ‘0‘ + hex;
				}
				sb.append(hex.toUpperCase());
			}
			return sb.toString();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (NoSuchPaddingException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		}
		return null;
	}
 
	/**
	 * 解密
	 * 
	 * 
	 */
	public static String Dcodes(String content, String key) {
		if (content == null || content.length() < 1)
			return null;
 
		if (content.trim().length() < 19)
			return content;
 
		byte[] byteRresult = new byte[content.length() / 2];
		for (int i = 0; i < content.length() / 2; i++) {
			int high = Integer.parseInt(content.substring(i * 2, i * 2 + 1), 16);
			int low = Integer.parseInt(content.substring(i * 2 + 1, i * 2 + 2), 16);
			byteRresult[i] = (byte) (high * 16 + low);
		}
		try {
			KeyGenerator kgen = KeyGenerator.getInstance("AES");
			kgen.init(128, new SecureRandom(key.getBytes()));
			SecretKey secretKey = kgen.generateKey();
			byte[] enCodeFormat = secretKey.getEncoded();
			SecretKeySpec secretKeySpec = new SecretKeySpec(enCodeFormat, "AES");
			Cipher cipher = Cipher.getInstance("AES");
			cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
			byte[] result = cipher.doFinal(byteRresult);
			return new String(result);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (NoSuchPaddingException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		}
		return null;
	}
 
	/**
	 * 详细解释
	 * 【ceet为加密的密匙】
	 * 【admin为需要加密的字符串】
	 * 【67BE5ED967DBA9B9810C295BE6DEF5D5为解密后的字符串】
	 * 【如果更改ceet，那么67BE5ED967DBA9B9810C295BE6DEF5D5字符串会发生变化】
	 * @param args
	 */
	// 调用测试
	public static void main(String[] args) {
		System.out.println("需要加密的内容："+Ecodes("admin", "ceet"));
		System.out.println("经过解密的内容："+Dcodes("67BE5ED967DBA9B9810C295BE6DEF5D5", "ceet"));
	}
}