简单自定义鉴权接口规则

接口鉴权分两部分

1. token为时间戳[但要求为80-120分钟之前时间范围内的一个时间戳]，默认设定为90分钟前，则token有效期为30分钟，服务端判断时间戳的有效范围；范围可自定义

• token 类型Long 提取当前时间90分钟前时刻的时间戳
• sign 类型 String 时间戳token进行md5后，取前8位

2. 签名sign，对token值进行md5(可加盐)，然后提取md5后字符串的前8位(规则可自定义)

有效URL生成之后，通常有一个有效期，默认设置为30分钟；此方法简单粗暴有效，土鳖算法，普通的小项目合作足够满足。

package com.learnworm.common.tools;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Calendar;
import java.util.Date;


public class Md5Tool {

    private static final int DEFAULT_EXPIRE_TIME = 90;
    private static final int DEFAULT_EXPIRE_TIMEOUT = 30;

    
    public String md5s(String plainText) {
        String str = null;
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(plainText.getBytes());
            byte b[] = md.digest();
            int i;
            StringBuffer buf = new StringBuffer("");
            for (int offset = 0; offset < b.length; offset++) {
                i = b[offset];
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }
            str = buf.toString();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return str;
    }

    
    public Long createTimestamp(int min) {
        Calendar c = Calendar.getInstance();
        c.setTime(new Date());
        c.add(Calendar.MINUTE, -min);
        return c.getTime().getTime();
    }

    
    public String createSign(){
        Long timestamp = createTimestamp(DEFAULT_EXPIRE_TIME);
        return md5s(timestamp.toString()).substring(0,8);
    }

    
    public String createSign(Long timestamp){
        if (timestamp==null){
            timestamp = createTimestamp(DEFAULT_EXPIRE_TIME);
        }
        return md5s(timestamp.toString()).substring(0,8);
    }

    
    public int getMinutesDiff(Date stopDate, Long startDate) {
        long t2 = stopDate.getTime();
        long t1 = startDate;
        int diff = (int) ((t2 - t1) / 60000L);
        diff += (t2 > t1 + diff * 60000L ? 1 : 0);
        return diff;
    }

    
    public boolean checkToken(Long timestamp){
        boolean isValid = false;
        Date date = new Date();
        int diff = getMinutesDiff(date,timestamp);
        System.out.println(timestamp+"===checkToken===="+diff);
        if (diff>DEFAULT_EXPIRE_TIME-10 && diff < DEFAULT_EXPIRE_TIME+DEFAULT_EXPIRE_TIMEOUT){
            isValid = true;
        }
        System.out.println(isValid);
        return isValid;
    }

    
    public boolean checkSign(Long timestamp,String sign){
        boolean isValid = false;
        String calcSign = createSign(timestamp);
        if (calcSign.equals(sign)){
            isValid = true;
        }
        System.out.println(calcSign+"===checkSign====="+sign+"====="+isValid);
        return isValid;
    }

    public static void main(String agrs[]) {
        Md5Tool md51 = new Md5Tool();
        int point = 90;
        String sign = null;
        Long token = null;
        token = md51.createTimestamp(point);
        sign = md51.md5s(token.toString());
        System.out.println(token+"========"+sign.substring(0,8));
    }
}