SimpleCacheStorage - Simple File Cache System

SimpleCacheStorage

package com.kirin.util;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import android.content.Context;

/**
 * Simple Cache System
 * @author 阿目
 *
 */
public class SimpleCacheStorage {

  private static final String TAG = "SimpleCacheStorage";
	private static final String PREFIX = "_CACHED_";
	
	/**
	 * 
	 * @param context
	 * @param key
	 * @param data
	 * @return success Saving or not
	 */
	public static boolean pull(Context context , String key , String data){
		FileOutputStream fos = null;
		try {
			fos = context.openFileOutput( PREFIX + md5(key), Context.MODE_PRIVATE);
			fos.write(data.getBytes());
			fos.flush();
			fos.close();
			return true;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
			return false;
		} catch (IOException e) {
			e.printStackTrace();
			return false;
		}
	}
	
	/**
	 * 
	 * @param context
	 * @param key
	 * @return Cached Data
	 */
	public static String get(Context context , String key){
		String datax = "";
        try {
            FileInputStream fIn = context.openFileInput ( PREFIX + md5(key) ) ;
            InputStreamReader isr = new InputStreamReader ( fIn ) ;
            BufferedReader buffreader = new BufferedReader ( isr ) ;

            String readString = buffreader.readLine () ;
            while ( readString != null ) {
                datax = datax + readString ;
                readString = buffreader.readLine () ;
            }

            isr.close () ;
        } catch ( IOException ioe ) {
            ioe.printStackTrace () ;
            return null;
        }
        return datax ;
	}
	
	/**
	 * Local use for hash the key word
	 * @param s
	 * @return
	 */
	private static String md5(String s) {
	    try {
	        // Create MD5 Hash
	        MessageDigest digest = java.security.MessageDigest.getInstance("MD5");
	        digest.update(s.getBytes());
	        byte messageDigest[] = digest.digest();

	        // Create Hex String
	        StringBuffer hexString = new StringBuffer();
	        for (int i=0; i<messageDigest.length; i++)
	            hexString.append(Integer.toHexString(0xFF & messageDigest[i]));
	        return hexString.toString();

	    } catch (NoSuchAlgorithmException e) {
	        e.printStackTrace();
	    }
	    return "";
	}
	
}