FileCache.java

/*
 * The MIT License (MIT)
 * 
 * Copyright � 2013 Clover Studio Ltd. All rights reserved.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.cloverstudio.spikademo.lazy;

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

import android.content.Context;
import android.graphics.Bitmap;

/**
 * FileCache
 * 
 * Used for managing files from application's file cache directory.
 */

public class FileCache {
    
    private File cacheDir;
    
    public FileCache(Context context){
        //Find the dir to save cached images
        if (android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED))
            cacheDir=new File(android.os.Environment.getExternalStorageDirectory(),"HookUpFileCache");
        else
            cacheDir=context.getCacheDir();
        if(!cacheDir.exists())
            cacheDir.mkdirs();
    }
    
    public File getFile(String identifier){
        //I identify images by hashcode. Not a perfect solution, good for the demo.
        String filename=String.valueOf(identifier.hashCode());
        //Another possible solution (thanks to grantland)
        //String filename = URLEncoder.encode(url);
        File f = new File(cacheDir, filename);
        return f;
        
    }
    
    public void clear(){
        File[] files=cacheDir.listFiles();
        if(files==null)
            return;
        for(File f:files)
            f.delete();
    }
    
    public void putImageToCache(Bitmap bitmap, String identifier) {
        String filename = String.valueOf(identifier.hashCode());
        File file = new File(cacheDir, filename);
        FileOutputStream fOut;
        try {
            fOut = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.PNG, 85, fOut);
            fOut.flush();
            fOut.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }


}