拿来即用DES加密解密算法

拿来即用DES加密解密算法

import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import java.util.Base64;
import java.util.Base64.*;

/**
 * 
 * @author 港港
 *
 */
public class DESUtil {

	private static Key key;
	// 设置**key
	private static String KEY_STR = "ganggang";
	private static String CHARSETNAME = "UTF-8";
	private static String ALGORITHM = "DES";

	static {
		try {
			// 生成DES算法对象
			KeyGenerator generator = KeyGenerator.getInstance(ALGORITHM);
			// 运用SHA1安全策略
			SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
			// 设置上**种子
			secureRandom.setSeed(KEY_STR.getBytes());
			// 初始化基于SHA1的算法对象
			generator.init(secureRandom);
			// 生成**对象
			key = generator.generateKey();
			generator = null;
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * 获取加密后的信息
	 * 
	 * @param str
	 * @return
	 */
	public static String getEncryptString(String str) {
		// 基于BASE64编码，接收byte[]并转换成String
		//BASE64Encoder base64encoder = new BASE64Encoder();
		Encoder base64encoder = Base64.getEncoder();
		try {
			// 按UTF8编码
			byte[] bytes = str.getBytes(CHARSETNAME);
			// 获取加密对象
			Cipher cipher = Cipher.getInstance(ALGORITHM);
			// 初始化密码信息
			cipher.init(Cipher.ENCRYPT_MODE, key);
			// 加密
			byte[] doFinal = cipher.doFinal(bytes);
			// byte[]to encode好的String并返回
//			return base64encoder.encode(doFinal);
			return base64encoder.encodeToString(doFinal);
		} catch (Exception e) {
			// TODO: handle exception
			throw new RuntimeException(e);
		}
	}

	/**
	 * 获取解密之后的信息
	 * 
	 * @param str
	 * @return
	 */
	public static String getDecryptString(String str) {
		// 基于BASE64编码，接收byte[]并转换成String
//		BASE64Decoder base64decoder = new BASE64Decoder();
		Decoder base64decoder = Base64.getDecoder();
		try {
			// 将字符串decode成byte[]
//			byte[] bytes = base64decoder.decodeBuffer(str);
			byte[] bytes = base64decoder.decode(str);
			// 获取解密对象
			Cipher cipher = Cipher.getInstance(ALGORITHM);
			// 初始化解密信息
			cipher.init(Cipher.DECRYPT_MODE, key);
			// 解密
			byte[] doFinal = cipher.doFinal(bytes);
			// 返回解密之后的信息
			return new String(doFinal, CHARSETNAME);
		} catch (Exception e) {
			// TODO: handle exception
			throw new RuntimeException(e);
		}
	}

	public static void main(String[] args) {
		System.out.println(getEncryptString("root"));
		System.out.println(getDecryptString("WnplV/ietfQ="));
	}

}