HW5.java

import java.util.Scanner;
import java.io.FileInputStream;
import java.io.BufferedInputStream;
import java.io.FileOutputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;

public class Recover {
  public static void main(String[] args) throws IOException{
    int[] test1 = {0xff, 0xd8, 0xff, 0xe0};
    int[] test2 = {0xff, 0xd8, 0xff, 0xe1};
    int[] check = new int[4];
    int image = 0;
    int counts = 0;
    String path = "/home/linux/ieng6/cs11wb/public/HW5/card.raw";
    FileInputStream infs  = new FileInputStream(path);
    BufferedInputStream inbfs = new BufferedInputStream(infs);
    while (!checkNewFile(check, test1, test2)) {  // to locate the start point.
      for (int i = 0; i < 4; i++) {
        check[i] = inbfs.read();
      }
    }
    while (check[0] != -1) {
      counts++;
      FileOutputStream outfs = new FileOutputStream(counts + ".jpg");
      BufferedOutputStream outbfs = new BufferedOutputStream(outfs);
    do {
      for (int i = 0; i < 4; i++) {
        outbfs.write(check[i]);
      }
      for (int i = 0; i < 508; i++) {
        outbfs.write(inbfs.read());
      }
      for (int i = 0; i < 4; i++) {
        check[i] = inbfs.read();
      }
      if (check[0] == -1) {
        outbfs.close();
        inbfs.close();
        break;
      }
    } while (!checkNewFile(check, test1, test2));
    outbfs.close();
    }
  }
  
  public static boolean checkNewFile(int[] check, int[] test1, int[] test2) {
    boolean result = false;
    for (int i = 0; i < check.length; i++) {
      if (check[i] == test1[i] || check[i] == test2[i]) {
        result = true;
      }
      else {
        result = false;
        break;
      }
    }
    return result;
  }
}