一文让你轻松了解JAVA开发中的四种加密方法

文章目录

一、工具类

1. md5加密工具类
2. base64加密工具类
3. Bcrypt工具类

二、加密测试

1. MD5加密测试
2. base64加密测试
3. SHA加密测试
4. BCrypt加密测试

一、工具类

1. md5加密工具类

package 加密Tester.util;
import java.security.MessageDigest;

public class MD5Utils {

    private static final String hexDigIts[] = {"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"};

    /** * MD5加密 * @param origin 字符 * @param charsetname 编码 * @return */
    public static String MD5Encode(String origin, String charsetname){
        String resultString = null;
        try{
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if(null == charsetname || "".equals(charsetname)){
                resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
            }else{
                resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
            }
        }catch (Exception e){
        }
        return resultString;
    }


    public static String byteArrayToHexString(byte b[]){
        StringBuffer resultSb = new StringBuffer();
        for(int i = 0; i < b.length; i++){
            resultSb.append(byteToHexString(b[i]));
        }
        return resultSb.toString();
    }

    public static String byteToHexString(byte b){
        int n = b;
        if(n < 0){
            n += 256;
        }
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigIts[d1] + hexDigIts[d2];
    }

}

2. base64加密工具类

package 加密Tester.util;
import org.apache.commons.codec.binary.Base64;
import java.io.UnsupportedEncodingException;

public class Base64Util {

    // 字符串编码
    private static final String UTF_8 = "UTF-8";

    /** * 加密字符串 * @param inputData * @return */
    public static String decodeData(String inputData) {
        try {
            if (null == inputData) {
                return null;
            }
            return new String(Base64.decodeBase64(inputData.getBytes(UTF_8)), UTF_8);
        } catch (UnsupportedEncodingException e) {
        }
        return null;
    }

    /** * 解密加密后的字符串 * @param inputData * @return */
    public static String encodeData(String inputData) {
        try {
            if (null == inputData) {
                return null;
            }
            return new String(Base64.encodeBase64(inputData.getBytes(UTF_8)), UTF_8);
        } catch (UnsupportedEncodingException e) {
        }
        return null;
    }

    public static void main(String[] args) {
        System.out.println(Base64Util.encodeData("我是中文"));
        String enStr = Base64Util.encodeData("我是中文");
        System.out.println(Base64Util.decodeData(enStr));
    }
}

3. Bcrypt工具类

package 加密Tester.util;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;
import org.mindrot.bcrypt.BCrypt;

public class BcryptCipher {
	// generate salt seed
	private static final int SALT_SEED = 12;
	// the head fo salt
	private static final String SALT_STARTSWITH = "$2a$12";
	
	public static final String SALT_KEY = "salt";
	
	public static final String CIPHER_KEY = "cipher";
	
	/** * Bcrypt encryption algorithm method * @param encryptSource * need to encrypt the string * @return Map , two values in Map , salt and cipher */
	public static Map<String, String> Bcrypt(final String encryptSource) {
		String salt  = BCrypt.gensalt(SALT_SEED);
		Map<String, String> bcryptResult = Bcrypt(salt, encryptSource);
		return bcryptResult;
	}
	/** * * @param salt encrypt salt, Must conform to the rules * @param encryptSource * @return */
	public static Map<String, String> Bcrypt(final String salt, final String encryptSource) {
		if (StringUtils.isBlank(encryptSource)) {
			throw new RuntimeException("Bcrypt encrypt input params can not be empty");
		}
		
		if (StringUtils.isBlank(salt) || salt.length() != 29) {
			throw new RuntimeException("Salt can't be empty and length must be to 29");
		}
		if (!salt.startsWith(SALT_STARTSWITH)) {
			throw new RuntimeException("Invalid salt version, salt version is $2a$12");
		}
		
		String cipher = BCrypt.hashpw(encryptSource, salt);
		Map<String, String> bcryptResult = new HashMap<String, String>();
		bcryptResult.put(SALT_KEY, salt);
		bcryptResult.put(CIPHER_KEY, cipher);
		return bcryptResult;
	}
	
}

二、加密测试

1. MD5加密测试

package 加密Tester;

import 加密Tester.util.MD5Utils;

/** * MD5加密 */
public class MD5Test {
	public static void main(String[] args) {
		String string = "我是一句话";
		String byteArrayToHexString = MD5Utils.byteArrayToHexString(string.getBytes());
		System.out.println(byteArrayToHexString);//e68891e698afe4b880e58fa5e8af9d

	}
}

2. base64加密测试

package 加密Tester;

import java.util.Base64;

import 加密Tester.util.Base64Util;

/** * base64加密 */
public class Bast64Tester {
	
	public static void main(String[] args) {
		String string = "我是一个字符串";
		String encodeData = Base64Util.encodeData(string); //加密
		String decodeData = Base64Util.decodeData(encodeData); //解密
		System.out.println(encodeData);//5oiR5piv5LiA5Liq5a2X56ym5Liy
		System.out.println(decodeData);//我是一个字符串

	}

}

3. SHA加密测试

package 加密Tester;

import org.apache.commons.codec.digest.Sha2Crypt;

/** * SHA加密 */
public class ShaTest {
	
	public static void main(String[] args) {
		String string = "我是一句话";
		
		String sha256Crypt = Sha2Crypt.sha256Crypt(string.getBytes());
		System.out.println(sha256Crypt);//$5$AFoQTeyt$TiqmobvcQXjXaAQMYosAAO4KI8LfigZMGHzq.Dlp4NC

	}
}

4. BCrypt加密测试

package 加密Tester;

import java.security.SecureRandom;
import java.util.Map;
import java.util.UUID;

import 加密Tester.util.BcryptCipher;
import 加密Tester.util.MD5Utils;

/** * BCrypt加密 */
public class BCryptTest {

	public static void main(String[] args) {
		
		String string = "我是一句话";
		Map<String, String> bcrypt = BcryptCipher.Bcrypt(string);
		System.out.println(bcrypt.keySet()); //[cipher, salt]
		
		System.out.println(bcrypt.get("cipher")); //$2a$12$ylb92Z84gqlrSfzIztlCV.dK0xNbw.pOv3UwXXA76llOsNRTJsE/.
		System.out.println(bcrypt.get("salt")); //$2a$12$ylb92Z84gqlrSfzIztlCV.
		
		Map<String, String> bcrypt2 = BcryptCipher.Bcrypt(bcrypt.get("salt"),string);
		System.out.println(bcrypt2.get("SALT_KEY")); //null
		System.out.println(bcrypt2.get("CIPHER_KEY")); //null 
	}
}