package com.zd.base.app;

import java.io.ByteArrayOutputStream;

/**
 * hex 转换
 * @author dgs
 * @time 2023-04-11
 */
public class HexStrUtils {

    private static String hexString = "0123456789ABCDEFabcdef";

    public static String encode(String str) {
        byte[] bytes = str.getBytes();
        StringBuilder sb = new StringBuilder(bytes.length * 2);
        //转换hex编码
        for (byte b : bytes) {
            sb.append(Integer.toHexString(b + 0x800).substring(1));
        }
        str = sb.toString();
        return str;
    }

    //把hex编码转换为string
    public static String decode(String bytes) {
        bytes = bytes.toUpperCase();
        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());
    }
}