savefileio.java

俄罗斯方块。适用于初学者学习。想念很好

package xn.tetris;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

 /**
  *存储最高分 最高等级 最高分创造者到文件myTetris.dat
  * */

public class SaveFileIO {

	private Tea tea;
	private final static int[] KEY = new int[]{//加密解密所用的KEY
		0x789f5645, 0xf68bd5a4,
		0x81963ffa, 0x458fac58
	};
	private BufferedInputStream input;
	private BufferedOutputStream output;
	private FileInputStream fileInput;
	private FileOutputStream fileOutput;
	private static File saveFile = new File("myTetris.dat");
	private String finalStr;
	
	public SaveFileIO(){
		tea = new Tea();
	}
	//从文件读出数据
	public String[] readFromFile() throws IOException{
		if(!saveFile.exists()){//若文件不存在
			return new String[]{
					"Are you the winner?", "0", "1"
			};
		}
		fileInput = new FileInputStream(saveFile);
		input = new BufferedInputStream(fileInput);

		int length = input.read();
		byte[] fileRead = new byte[length];
		input.read(fileRead, 0, length);
		String finalRead = decryptByTea(fileRead);

		input.close();
		return finalRead.split("/ /");
		
	}
	//往文件中写数据
	public void writeToFile(String creatorName, int highestScore, int highestLevel) throws IOException{
		
		fileOutput = new FileOutputStream(saveFile);
		output = new BufferedOutputStream(fileOutput);
		
		finalStr = creatorName + "/ /" + highestScore + "/ /" + highestLevel;
		
		byte[] tempWrite = encryptByTea(finalStr);
		int length = tempWrite.length;
		byte[] finalWrite = new byte[length + 1];
		finalWrite[0] = (byte) length;
		System.arraycopy(tempWrite, 0, finalWrite, 1, length);
		
		output.write(finalWrite, 0, finalWrite.length);
		output.close();
	}
	//通过TEA算法加密需要存储到文件里的信息
	private byte[] encryptByTea(String info){
		byte[] temp = info.getBytes();
		int n = 8 - temp.length % 8;//若temp的个数不足8的倍数,需要填充的位数
		byte[] encryptStr = new byte[temp.length + n];
		encryptStr[0] = (byte)n;
		System.arraycopy(temp, 0, encryptStr, n, temp.length);
		byte[] result = new byte[encryptStr.length];
		for(int offset = 0; offset < result.length; offset += 8){
			byte[] tempEncrpt = tea.encrypt(encryptStr, offset, KEY, 32);
			System.arraycopy(tempEncrpt, 0, result, offset, 8);
		}
		return result;
	}
	//通过TEA算法解密存储在文件里的信息
	private String decryptByTea(byte[] secretInfo){
		byte[] decryptStr = null;
		byte[] tempDecrypt = new byte[secretInfo.length];
		for(int offset = 0; offset < secretInfo.length; offset += 8){
			decryptStr = tea.decrypt(secretInfo, offset, KEY, 32);
			System.arraycopy(decryptStr, 0, tempDecrypt, offset, 8);
		}
		
		int n = tempDecrypt[0];
		return new String(tempDecrypt, n, decryptStr.length - n);
		
	}
	
	/*public static void main(String[] args){
		String info = "www.blogjava.net/orangehf";
		System.out.println("原数据：" + info);
		
		SaveFileIO io = new SaveFileIO();
		
		byte[] encryptInfo = io.encryptByTea(info);
		System.out.print("加密后的数据：");
		for(byte i : encryptInfo)
			System.out.print(i + " ");
		System.out.println();
		
		String decryptInfo = io.decryptByTea(encryptInfo);
		System.out.print("解密后的数据：");
		System.out.println(decryptInfo);
		
	}*/
	
}