Base64
简介
Base64是基于64个可打印字符(a-z,A-Z,0-9,+、/)来显示2进制数据，它用于传输8Bit字节代码，并在网络传输中广泛应用或者本地存储字节数组。不是加密和解密
使用示例
public class Base64Test {public static final String UTF= StandardCharsets.UTF_8.name();@Testpublic void test1() throws UnsupportedEncodingException {String message = "法律a";byte[] encode = Base64.getEncoder().encode(message.getBytes(UTF));System.out.println(Arrays.toString(encode));String enCodeStr = new String(encode, UTF);System.out.println(enCodeStr);byte[] decode = Base64.getDecoder().decode(enCodeStr.getBytes(UTF));String deCodeStr = new String(decode, UTF);System.out.println(deCodeStr);}@Testpublic void test2() throws UnsupportedEncodingException {String message = "法律a";byte[] encode = org.apache.commons.codec.binary.Base64.encodeBase64(message.getBytes(UTF));String enCodeStr = new String(encode, UTF);System.out.println(enCodeStr);byte[] decode = org.apache.commons.codec.binary.Base64.decodeBase64(enCodeStr.getBytes(UTF));String deCodeStr = new String(decode, UTF);System.out.println(deCodeStr);}
}URL编码
简介
当 URL 路径或者查询参数中，带有中文或者特殊字符的时候，就需要对 URL 进行编码（采用十六进制编码格式）。URL 编码的原则是使用安全字符去表示那些不安全的字符
使用示例
public class UrlCodeTest {public static final String UTF= StandardCharsets.UTF_8.name();public static final String DEMO_STR= "法律";@Testpublic void test1() throws UnsupportedEncodingException {String encodeStr = URLEncoder.encode(DEMO_STR, UTF);System.out.println("url encode result is :" + encodeStr);String decodeStr = URLDecoder.decode(encodeStr, UTF);System.out.println("url decode result is :" + decodeStr);}
}摘要算法
简介
又叫Hash算法、散列函数、数字摘要、消息摘要，是一种单向算法(不可逆)，可以根据该算法对目标信息生成固定长度的唯一hash值，不能逆向计算(不可通过计算的hash值反推目标信息)。其中较为常用的：
MD5、SHA-256、SHA-512
HmacMD5、HmacSHA256、HmacSHA512
使用示例
MD5
D5算法将字符串转换成128位-->16个字节，转换成16进制字符创表示，一个16进制数字占4位，所以最后的MD5值都是用32个16进制数字表示
public class Md5Test {public static final String UTF= StandardCharsets.UTF_8.name();public static final String MD_NAME= "MD5";public static final String DEMO_STR= "法律";/*** jdk原始*/@Testpublic void test1() throws NoSuchAlgorithmException, UnsupportedEncodingException {String digest = MessageDigestUtil.digest(DEMO_STR, MD_NAME);// c47d7a21cdb9a974df82eef105477becSystem.out.println(digest);}/*** codec原始*/@Testpublic void test2() throws NoSuchAlgorithmException, UnsupportedEncodingException {String s = DigestUtils.md5Hex(DEMO_STR);// c47d7a21cdb9a974df82eef105477bec// c47d7a21cdb9a974df82eef105477becSystem.out.println(s);}
}SHA-256
SHA-256和MD5算法差不多，消息摘要算法，不可逆。不管字符串长度多少，生成一个固定长度的字符串，SHA-256生成一个256位--也就是32个字节，转换成16进制字符之后是62个字符长度的字符串
/*** SHA-256和MD5算法差不多** 消息摘要算法，不可逆。不管字符串长度多少，生成一个固定长度的字符串** SHA-256生成一个256位--也就是32个字节** 转换成16进制字符之后是62个字符长度的字符串*/
public class Sha256Test {public static final String ALGORITHM_NAME= "SHA-256"; // 算法名称public static final String DEMO_STR= "法律";/*** jdk原生的SHA-256*/@Testpublic void test1() {String digest = MessageDigestUtil.digest(DEMO_STR, ALGORITHM_NAME);// 32bc0a3372fcf9cb2699e5d46eb51d73081d65bb18d82af3929001ee2240af6aSystem.out.println(digest);}/*** codec包的SHA-256*/@Testpublic void test2() {String digest = DigestUtils.sha256Hex(DEMO_STR);// 32bc0a3372fcf9cb2699e5d46eb51d73081d65bb18d82af3929001ee2240af6a （jdk原生）// 32bc0a3372fcf9cb2699e5d46eb51d73081d65bb18d82af3929001ee2240af6a (codec)System.out.println(digest);}
}SHA-512
HA-512、SHA-256和MD5算法差不多
消息摘要算法，不可逆。不管字符串长度多少，生成一个固定长度的字符串，SHA-512生成一个512位--也就是64个字节，转换成16进制字符之后是128个字符长度的字符串
/*** SHA-512、SHA-256和MD5算法差不多** 消息摘要算法，不可逆。不管字符串长度多少，生成一个固定长度的字符串** SHA-512生成一个512位--也就是64个字节** 转换成16进制字符之后是128个字符长度的字符串*/
public class Sha512Test {public static final String ALGORITHM_NAME= "SHA-512"; // 算法名称public static final String DEMO_STR= "法律";/*** jdk原生的SHA-512*/@Testpublic void test1() {String digest = MessageDigestUtil.digest(DEMO_STR, ALGORITHM_NAME);// 2001a3d435c3180120e9b748faf08bebae6a51c717ea21575771e68561da76fb8e4cdb48691aafc1a8b062ba54ab9680d656b9b28beedc948d01bd24d83082daSystem.out.println(digest);}/*** codec包的SHA-512*/@Testpublic void test2() {String digest = DigestUtils.sha512Hex(DEMO_STR);// 2001a3d435c3180120e9b748faf08bebae6a51c717ea21575771e68561da76fb8e4cdb48691aafc1a8b062ba54ab9680d656b9b28beedc948d01bd24d83082da （jdk原生）// 2001a3d435c3180120e9b748faf08bebae6a51c717ea21575771e68561da76fb8e4cdb48691aafc1a8b062ba54ab9680d656b9b28beedc948d01bd24d83082da (codec)System.out.println(digest);}
}public class MessageDigestUtil {public static final String UTF8= StandardCharsets.UTF_8.name();/*** 摘要算法** @param sourceStr 原始字符串* @param algorithm 算法名称如：MD5、SHA-256、SHA-512* @return 16进制字符串*/public static String digest(String sourceStr,String algorithm) {try {MessageDigest md = MessageDigest.getInstance(algorithm);// 结果字节数组byte[] digest = md.digest(sourceStr.getBytes(UTF8));// 转换成16进制字符串return HexUtil.transBytes2HexStr(digest);} catch (NoSuchAlgorithmException | UnsupportedEncodingException e) {e.printStackTrace();}return null;}/*** mac签名算法** @param sourceStr 原始字符串* @param key 秘钥* @param algorithm 算法名称，如：HmacMD5 HmacSha-256、HmacSha-512* @return 16进制字符串*/public static String macDigest(String sourceStr,String key,String algorithm) {try {// mac实例Mac mac = Mac.getInstance(algorithm);// 创建秘钥对SecretKey secretKey = new SecretKeySpec(key.getBytes(UTF8),algorithm);// 初始化macmac.init(secretKey);// 原始字符串字节数组byte[] originalBytes = sourceStr.getBytes(UTF8);// 结果字节数组byte[] bytes = mac.doFinal(originalBytes);// 转换成16进制字符串return HexUtil.transBytes2HexStr(bytes);} catch (NoSuchAlgorithmException | InvalidKeyException | UnsupportedEncodingException e) {e.printStackTrace();}return null;}
}public class HexUtil {/*** 字节数组转字16进制符串** @param digest 字节数组* @return 16进制字符串*/public static String transBytes2HexStr(byte[] digest) {StringBuilder builder = new StringBuilder();for (byte b : digest) {String s = Integer.toHexString(((int) b) & 0xff);if(s.length() == 1) {s = "0" + s;}builder.append(s);}return builder.toString();}/*** 16进制字符串转byte数组** @param hexStr 16进制字符串* @return 字节数组*/public static byte[] transHexStr2Bytes(String hexStr) {int length = hexStr.length();if (length % 2!=0) {throw new RuntimeException("hexStr length must be even number!");}byte[] bytes = new byte[length/2];for (int i = 0;i<bytes.length;i++) {int high4 = Integer.parseInt(hexStr.substring(i*2,i*2 +1),16);int low4 = Integer.parseInt(hexStr.substring(i*2+1,i*2 + 2),16);bytes[i] = (byte)(high4 * 16 + low4);}return bytes;}
}mac摘要
Message Authentication Code 消息验证码，比摘要算法安全性更高，加入了一个秘钥
HmacMd5对应md5摘要算法，生成一个128位数字--16个字节，转换成16进制数字字符之后是32个字符
HmacSha256对应SHA-256摘要算法，生成一个256位数字--32个字节，转换成16进制数字字符之后是64个字符
HmacSha512对应SHA-512摘要算法，生成一个512位数字--64个字节，转换成16进制数字字符之后是128个字符
/*** mac类摘要算法* Message Authentication Code 消息验证码** 比摘要算法安全性更高，加入了一个秘钥** HmacMd5对应md5摘要算法，生成一个128位数字--16个字节，转换成16进制数字字符之后是32个字符** HmacSha256对应SHA-256摘要算法，生成一个256位数字--32个字节，转换成16进制数字字符之后是64个字符** HmacSha512对应SHA-512摘要算法，生成一个512位数字--64个字节，转换成16进制数字字符之后是128个字符*/
public class HmacTest {public static final String ALGORITHM_NAME= "SHA-256"; // 算法名称public static final String DEMO_STR= "法律";/*** jdk原生mac摘要算法*/@Testpublic void test1() {String key = "123";String hmacMD5Str = MessageDigestUtil.macDigest(DEMO_STR, key, "HmacMD5");// 2c50de960b42c1f86b3ba22e9de9e49fSystem.out.println("hmacMD5Str:" + hmacMD5Str);String hmacSHA256 = MessageDigestUtil.macDigest(DEMO_STR, key, "HmacSHA256");// 2128ed9d2e29c971995bf65d06c1671f3b77344631da122f4e463d07b9257e61System.out.println("hmacSHA256:" + hmacSHA256);String hmacSHA512 = MessageDigestUtil.macDigest(DEMO_STR, key, "HmacSHA512");// 381586ca8518b05799fe603805393afdac07e54af11fc9b04b8df6b644b77dfa37a6b0691f67d7b5a4ef1989d7751328a1d045c6ef26608062f51eac84bd6efaSystem.out.println("hmacSHA512:" + hmacSHA512);}/*** codec的mac摘要算法*/@Testpublic void test2() {String key = "123";String hmacMd5Str = new HmacUtils(HmacAlgorithms.HMAC_MD5, key).hmacHex(DEMO_STR);// 2c50de960b42c1f86b3ba22e9de9e49f(jdk原生)// 2c50de960b42c1f86b3ba22e9de9e49f(codec)System.out.println("hmacMd5Str:" + hmacMd5Str);String hmacSha255Str = new HmacUtils(HmacAlgorithms.HMAC_SHA_256, key).hmacHex(DEMO_STR);// 2128ed9d2e29c971995bf65d06c1671f3b77344631da122f4e463d07b9257e61(jdk原生)// 2128ed9d2e29c971995bf65d06c1671f3b77344631da122f4e463d07b9257e61(codec)System.out.println("hmacSha255Str:" + hmacSha255Str);String hmacSha512Str = new HmacUtils(HmacAlgorithms.HMAC_SHA_512, key).hmacHex(DEMO_STR);// 381586ca8518b05799fe603805393afdac07e54af11fc9b04b8df6b644b77dfa37a6b0691f67d7b5a4ef1989d7751328a1d045c6ef26608062f51eac84bd6efa(jdk原生)// 381586ca8518b05799fe603805393afdac07e54af11fc9b04b8df6b644b77dfa37a6b0691f67d7b5a4ef1989d7751328a1d045c6ef26608062f51eac84bd6efa(codec)System.out.println("hmacSha512Str:" + hmacSha512Str);}
}
