月度归档:2013年12月

Scala 的类型挺奇怪的,我今天刚刚遇到

中文翻译叫协变

trait ObjectIdentityConveter[+T] {
def convert[K >: T](k: K): ObjectIdentity
}

可以编译过

trait ObjectIdentityConveter[+T] {
def convert(t: T): ObjectIdentity
}

就不行了

trait ObjectIdentityConveter[+T] {
protected[this] def convert(t: T): ObjectIdentity
}

也可以编译过

我真的不知道是为什么,正在学习中。

用 Scala 写一份 Intellij Idea 13 的注册机

尝试了一下,大约是 java 的 1/3 代码量

import java.util.Date
import java.util.zip.CRC32
import scala.util.Random

object Idea extends App {
  def MakeKey(name: String, days: Int, id: Int): String = {
    implicit def longToByte(i: Long) = i.asInstanceOf[Byte]
    val ld = new Date().getTime
    val bkey = Array[Byte](1, 13, ld & 255, ld >> 8 & 255, ld >> 16 & 255, ld >> 24 & 255, days & 255, days >> 8 & 255, 105, -59, 0, 0)
    val w = getCRC(name, id, bkey)
    bkey(10) = w & 255
    bkey(11) = w >> 8 & 255
    val k1 = BigInt(bkey).modPow(BigInt("89126272330128007543578052027888001981"), BigInt("86f71688cdd2612ca117d1f54bdae029", 16));
    "%05d".format(id) + "-" + encodeGroups(k1)

  }
  def encodeGroups(i: BigInt): String = {
    val beginner1 = 0x39aa400L
    def f(j: BigInt): Stream[(String)] = (if (j == 0) null else encodeGroup(j % beginner1)) #:: f(j / beginner1)
    f(i).takeWhile(_ != null).mkString("-")
  }
  def encodeGroup(i: BigInt): String = {
    def f(j: BigInt): Stream[Char] = {
      val k = j % 36
      (if (k < 10) (48 + k).toChar else (65 + k - 10).toChar) #:: f(j / 36)
    }
    f(i).take(5).mkString("")
  }
  def getCRC(s: String, i: Int, bytes: Array[Byte]): Short = {
    val crc32 = new CRC32
    s.foreach(crc32.update(_))
    crc32.update(i)
    crc32.update(i >> 8)
    crc32.update(i >> 16)
    crc32.update(i >> 24)
    bytes.slice(0, bytes.size - 2).foreach(crc32.update(_))
    crc32.getValue().toShort;
  }
  println(MakeKey("changhai", 0, Random.nextInt(100000)))
}

找了一个 Intellij Idea 13 的注册机

package com.doscala;

import java.math.BigInteger;
import java.util.Date;
import java.util.Random;
import java.util.zip.CRC32;

public class keygen
{
    /**
     * @param s
     * @param i
     * @param bytes
     * @return
     */
    public static short getCRC(String s, int i, byte bytes[])
    {
        CRC32 crc32 = new CRC32();
        if (s != null)
        {
            for (int j = 0; j < s.length(); j++)             {                 char c = s.charAt(j);                 crc32.update(c);             }         }         crc32.update(i);         crc32.update(i >> 8);
        crc32.update(i >> 16);
        crc32.update(i >> 24);
        for (int k = 0; k < bytes.length - 2; k++)         {             byte byte0 = bytes[k];             crc32.update(byte0);         }         return (short) (int) crc32.getValue();     }     /**      * @param biginteger      * @return String      */     public static String encodeGroups(BigInteger biginteger)     {         BigInteger beginner1 = BigInteger.valueOf(0x39aa400L);         StringBuilder sb = new StringBuilder();         for (int i = 0; biginteger.compareTo(BigInteger.ZERO) != 0; i++)         {             int j = biginteger.mod(beginner1).intValue();             String s1 = encodeGroup(j);             if (i > 0)
            {
                sb.append("-");
            }
            sb.append(s1);
            biginteger = biginteger.divide(beginner1);
        }
        return sb.toString();
    }

    /**
     * @param i
     * @return
     */
    public static String encodeGroup(int i)
    {
        StringBuilder sb = new StringBuilder();
        for (int j = 0; j < 5; j++)
        {
            int k = i % 36;
            char c;
            if (k < 10)             {                 c = (char) (48 + k);             }             else             {                 c = (char) ((65 + k) - 10);             }             sb.append(c);             i /= 36;         }         return sb.toString();     }     /**      * @param name      * @param days      * @param id      * @return      */     public static String MakeKey(String name, int days, int id)     {         id %= 100000;         byte bkey[] = new byte[12];         bkey[0] = (byte) 1; // Product type: IntelliJ IDEA is 1         bkey[1] = 13; // version         Date d = new Date();         long ld = (d.getTime() >> 16);
        bkey[2] = (byte) (ld & 255);
        bkey[3] = (byte) ((ld >> 8) & 255);
        bkey[4] = (byte) ((ld >> 16) & 255);
        bkey[5] = (byte) ((ld >> 24) & 255);
        days &= 0xffff;
        bkey[6] = (byte) (days & 255);
        bkey[7] = (byte) ((days >> 8) & 255);
        bkey[8] = 105;
        bkey[9] = -59;
        bkey[10] = 0;
        bkey[11] = 0;
        int w = getCRC(name, id % 100000, bkey);
        bkey[10] = (byte) (w & 255);
        bkey[11] = (byte) ((w >> 8) & 255);
        BigInteger pow = new BigInteger("89126272330128007543578052027888001981", 10);
        BigInteger mod = new BigInteger("86f71688cdd2612ca117d1f54bdae029", 16);
        BigInteger k0 = new BigInteger(bkey);
        BigInteger k1 = k0.modPow(pow, mod);
        String s0 = Integer.toString(id);
        String sz = "0";
        while (s0.length() != 5)
        {
            s0 = sz.concat(s0);
        }
        s0 = s0.concat("-");
        String s1 = encodeGroups(k1);
        s0 = s0.concat(s1);
        return s0;
    }

    public static void main(String[] args)
    {
        if (args.length == 0)
        {
            System.err.printf("*** Usage: %s name%n", keygen.class.getCanonicalName());
            System.exit(1);
        }
        Random r = new Random();
        System.out.println(MakeKey(args[0], 0, r.nextInt(100000)));
    }
}