Java中哈希算法总结_java 哈希

package com.apesource.demo02;
 
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
//MD5加密
public class Demo01 {
	public static void main(String[] args) throws NoSuchAlgorithmException {
		//创建基于MD5算法的消息摘要对象
		MessageDigest md5 = MessageDigest.getInstance("MD5");
		//更新原始数据
		md5.update("天王盖地虎".getBytes());
		//获取加密后的结果
		byte[] disgetsBytes = md5.digest();
		System.out.println("加密后的结果"+Arrays.toString(disgetsBytes));
		System.out.println("加密结果长度"+disgetsBytes.length);
	}
}
 

package com.apesource.demo02;
 
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
 
import com.apesource.demo.HashTools;
 
//按照MD5算法对图片进行"加密"
public class Demo02 {
	public static void main(String[] args) throws IOException, NoSuchAlgorithmException {
		//图片的原始字节内容
		byte[] imageBuf = Files.readAllBytes(Paths.get("C:\\Users\\Pictures\\xxx.jpg"));
		//创建基于MD5算法的消息摘要对象
		MessageDigest md5 = MessageDigest.getInstance("MD5");
		//原始字节内容(图片)
		md5.update(imageBuf);
		//获取加密摘要
		byte[] digestBytes = md5.digest();
		System.out.println("加密后的结果(字节数组)："+Arrays.toString(digestBytes));
		System.out.println("加密后的结果(16进制字符串)："+HashTools.bytesTohex(digestBytes));
		System.out.println("加密结果长度"+digestBytes.length);
	}
}

package com.apesource.demo02;
 
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
 
public class Demo03 {
	public static void main(String[] args) throws NoSuchAlgorithmException, UnsupportedEncodingException {
		//创建一个MessageDigest实例
		MessageDigest sha1 = MessageDigest.getInstance("SHA-1");
		//调用update输入数据:
		sha1.update("Hello".getBytes("UTF-8"));
		//f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0
		byte[] results = sha1.digest();
		StringBuilder ret = new StringBuilder();
		for(byte b : results) {
			//将字节数组转换为两位十六进制字符串
			ret.append(String.format("%02x", b));
		}
		System.out.println(ret.toString());
	}
}

package com.apesource.demo02;
 
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
 
//Hash算法(消息摘要算法)工具类
public class HashTools {
	//消息摘要对象
	private static MessageDigest digest;
	//构造方法
	private HashTools() {}
	//按照MD5进行消息摘要计算(哈希算法)
	public static String digestByMD5(String source) throws NoSuchAlgorithmException{
		digest = MessageDigest.getInstance("MD5");
		return handler(source);
	}
	//按照SHA-1进行消息摘要计算(哈希算法)
	public static String digestBySHA1(String source) throws NoSuchAlgorithmException{
		digest = MessageDigest.getInstance("SHA-1");
		return handler(source);
	}
	//通过消息摘要对象,处理加密内容
	public static String handler(String source) {
		digest.update(source.getBytes());
		byte[] bytes = digest.digest();
		String hash = bytesToHex(bytes);
		return hash;
	}
	//将字节数组转换为16进制字符串
	public static String bytesToHex(byte[] bytes) {
		StringBuilder ret = new StringBuilder();
		for(byte b : bytes) {
			//将字节数组转换为两位十六进制字符串
			ret.append(String.format("%02x", b));
		}
		return ret.toString();
	}
}

package com.apesource.demo02;
 
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.UUID;
 
import org.omg.PortableInterceptor.DISCARDING;
 
import com.apesource.demo.HashTools;
 
//通过随机加盐,解决彩虹表攻击问题
public class Demo04 {
	public static void main(String[] args) throws NoSuchAlgorithmException {
		//原始密码
		String password = "wbjxxmy";
		//属于即产生的盐值
		String salt = UUID.randomUUID().toString().substring(0,4);
		//创建基于SHA-1算法的消息摘要对象
		MessageDigest sha1 = MessageDigest.getInstance("SHA-1");
		sha1.update(password.getBytes());   //原始密码
		sha1.update(salt.getBytes());     //盐值
		//计算加密结果,SHA-1的输出结果为20个字节(40个字符)
		String digestHex = HashTools.bytesTohex(sha1.digest());
		System.out.println(digestHex);
	}
}

package com.apesource.demo02;
 
import java.security.NoSuchAlgorithmException;
 
//通过自定义工具类,完成对应加密处理
public class Demo05 {
	public static void main(String[] args) {
		try {
			//md5加密
			String md5 = HashTools.digestByMD5("wbjxxmy");
			//sha1加密
			String sha1 = HashTools.digestBySHA1("wbjxxmy");
			
			System.out.println("md5="+md5);
			System.out.println("sha1="+sha1);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
	}
}

package com.apesource.demo02;
 
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
 
import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
 
//Hmac算法
public class Demo06 {
	public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeyException {
		String password = "wbjxxmy";
		//一:产生秘钥
		//获取HmacMD5秘钥生成器
		KeyGenerator keyGen = KeyGenerator.getInstance("HmacMD5");
		//生成秘钥
		SecretKey key = keyGen.generateKey();
		System.out.println("秘钥："+Arrays.toString(key.getEncoded()));
		System.out.println("秘钥长度(64字节):"+key.getEncoded().length);
		System.out.println("秘钥："+HashTools.bytesToHex(key.getEncoded()));
		//二:使用秘钥,进行加密
		//获取HMac加密算法对象
		Mac mac = Mac.getInstance("HMacMD5");
		mac.init(key);   //初始化秘钥
		mac.update(password.getBytes());    //更新原始加密内容
		byte[] bytes = mac.doFinal();    //加密处理,并获取加密结果
		String result = HashTools.bytesToHex(bytes);     //加密结果处理成16进制字符串
		System.out.println("加密结果16进制字符串:"+result);
		System.out.println("加密结果(字节长度16字节):"+bytes.length);
		System.out.println("加密结果(字符长度32字符):"+result.length());
		
	}
}

package com.apesource.demo02;
 
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
 
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
 
//按照"字节数组" "字符串",恢复Hmac秘钥
public class Demo07 {
	public static void main(String[] args) {
		//原始密码
//		String password = "wbjxxmy";
//		//秘钥(字节数组)
//        byte[] keybytes = {-97, 63, -18, -128, -127, 25, -55, -12, 76, 79, -66, -41, -17, -74, -109, -21, 125, -101, -72, 61, -43, -116, 87, -63, -42, 87, -78, 16, -16, -10, 105, 127, -57, 21, 117, -115, -39, 17, 116, -99, 121, -43, -22, 61, -74, 21, -12, 121, 24, 94, -80, -2, -100, 110, -125, 101, -7, 14, -16, -9, -47, 117, 90, -59};
//        
		//秘钥(字符串)
		String keystr = "2990f480743ea992a358e76c169f8bc7d415d38d0e10541282a393e456dfc13dc3e8ed17f62ba06f36aeaed1d7ebaa67f7edbc743dd883a5954d361e841ba1cc";
//		//用于保存秘钥:秘钥长度为64字节
		byte[] keybytes = new byte[64];
		
		for(int i = 0,k = 0;i<keystr.length();i+=2,k++) {
			String s = keystr.substring(i, i+2);
			keybytes[k] = (byte)Integer.parseInt(s,16);  //转换成十六进制字节值
		}
         
		try {
			//恢复秘钥(字节数组)
			SecretKey key = new SecretKeySpec(keybytes,"HmacMD5");
	        //创建Hmac加密算法对象
			Mac mac = Mac.getInstance("HmacMD5");
	        mac.init(key);    //初始化秘钥
	        mac.update(password.getBytes());
	        String result = HashTools.bytesToHex(mac.doFinal());
	        //808956c674d77c826a8cbf0c594a8368
	        System.out.println(result);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		}
        
	}
}

package com.apesource.demo02;
 
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Security;
import java.util.Arrays;
 
import javax.crypto.SecretKey;
 
import org.bouncycastle.jce.provider.BouncyCastleProvider;
 
//第三方开源库提供的RipeMD160消息摘要算法实现
public class Demo08 {
	public static void main(String[] args) throws NoSuchAlgorithmException {
		//注册BouncyCastleProvider通知类
		//将提供的消息摘要算法注册至Security
		Security.addProvider(new BouncyCastleProvider());
		//获取RipeMD160算法的"消息摘要对象"(加密对象)
		MessageDigest ripeMd160 = MessageDigest.getInstance("RipeMD160");
		//更新原始数据
		ripeMd160.update("wbjxxmy".getBytes());
		//获取消息摘要(加密)
		byte[] result = ripeMd160.digest();
		//消息摘要的字节长度和内容
		System.out.println("加密结果(字节长度)"+result.length);   //160位 = 20字节
		System.out.println("加密结果(字节内容)"+Arrays.toString(result));
		//十六进制字符串
		String hex = new BigInteger(1,result).toString(16);
		System.out.println("加密结果(字符串长度)"+hex.length());   //20字节=40个字符
		System.out.println("加密结果(字符串内容)"+hex);
	}
}