3DES加密解密简单应用,都是代码你懂得-站在巨人的肩膀上

3DES加密

package des3
import java.io.ByteArrayOutputStream;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;

/**
*字符串 DESede(3DES) 加密
*/
public class Test3DES {
	private static final String Algorithm = "DESede"; // 定义 加密算法,可用 DES,DESede,Blowfish
	private static final String hexString="0123456789ABCDEF";
	/**
	 * 													 
	 * @param keybyte  加密密钥，长度为24字节
	 * @param src 	  字节数组(根据给定的字节数组构造一个密钥。 )
	 * @return
	 */
	public static byte[] encryptMode(byte[] keybyte, byte[] src) {
		try {
			// 根据给定的字节数组和算法构造一个密钥
			SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
			// 加密
			Cipher c1 = Cipher.getInstance(Algorithm);
			c1.init(Cipher.ENCRYPT_MODE, deskey);
			return c1.doFinal(src);
		} catch (java.security.NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (javax.crypto.NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (java.lang.Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	/**
	 * 
	 * @param keybyte 密钥
	 * @param src	    需要解密的数据
	 * @return
	 */
	public static byte[] decryptMode(byte[] keybyte, byte[] src) {
		try {
			// 生成密钥
			SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
			// 解密
			Cipher c1 = Cipher.getInstance(Algorithm);
			c1.init(Cipher.DECRYPT_MODE, deskey);
			return c1.doFinal(src);
		} catch (java.security.NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (javax.crypto.NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (java.lang.Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	/**
	 * 字符串转为16进制
	 * @param str
	 * @return
	 */
	public static String encode(String str) 
	{ 
		//根据默认编码获取字节数组 
		byte[] bytes=str.getBytes(); 
		StringBuilder sb=new StringBuilder(bytes.length*2); 

		//将字节数组中每个字节拆解成2位16进制整数 
		for(int i=0;i<bytes.length;i++) 
		{ 
			sb.append(hexString.charAt((bytes[i]&0xf0)>>4)); 
			sb.append(hexString.charAt((bytes[i]&0x0f)>>0)); 
		} 
		return sb.toString(); 
	} 
	/**
	 * 
	 * @param bytes
	 * @return
	 * 将16进制数字解码成字符串,适用于所有字符（包括中文） 
	 */ 
	public static String decode(String bytes) 
	{ 
		ByteArrayOutputStream baos=new ByteArrayOutputStream(bytes.length()/2); 
		//将每2位16进制整数组装成一个字节 
		for(int i=0;i<bytes.length();i+=2) 
			baos.write((hexString.indexOf(bytes.charAt(i))<<4 |hexString.indexOf(bytes.charAt(i+1)))); 
		return new String(baos.toByteArray()); 
	} 

	// 转换成十六进制字符串
	public static String byte2hex(byte[] b) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
			if (n < b.length - 1)
				hs = hs + ":";
		}
		return hs.toUpperCase();
	}

	public static void main(String[] args) {
		// 添加新安全算法,如果用JCE就要把它添加进去
		//这里addProvider方法是增加一个新的加密算法提供者(个人理解没有找到好的答案,求补充)
		Security.addProvider(new com.sun.crypto.provider.SunJCE());
		//byte数组(用来生成密钥的)
		final byte[] keyBytes = { 0x11, 0x22, 0x4F, 0x58, (byte)0x88, 0x10,
				0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD,
				0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,
				(byte) 0xE2 }; 
		String szSrc = "This is a 3DES test. 测试";
		System.out.println("加密前的字符串:" + szSrc);

		byte[] encoded = encryptMode(keyBytes, szSrc.getBytes());
		System.out.println("加密后的字符串:" + new String(encoded));

		byte[] srcBytes = decryptMode(keyBytes, encoded);
		System.out.println("解密后的字符串:" + new String(srcBytes));
		//------------------------------------------------------------
		String byt="字符串转换为16进制";
		byt=encode(byt);
		System.out.println(byt);
		byt=decode(byt);
		System.out.println(byt);

	}
}