LruCache

Cache.java

package util;

import com.jakewharton.disklrucache.DiskLruCache;

import java.io.File;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

public class Cache  {

    private DiskLruCache mDiskLruCache;

    public Cache(File directory) throws IOException {
        mDiskLruCache = DiskLruCache.open(directory, 1, 1, 20 * 2^20);
    }

    public void put(String key, Object object) {
        DiskLruCache.Editor editor;
        try {
            editor = mDiskLruCache.edit(key);
            if (editor == null) {
                return;
            }
            ObjectOutputStream out = new ObjectOutputStream(editor.newOutputStream(0));
            out.writeObject(object);
            out.close();
            editor.commit();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public Object get(String key) {
        DiskLruCache.Snapshot snapshot;
        try {
            snapshot = mDiskLruCache.get(key);
            if (snapshot==null)
                return "";
            ObjectInputStream in = new ObjectInputStream(snapshot.getInputStream(0));
            return in.readObject();
        } catch (IOException | ClassNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }
    public String isNullOrEmpty(String key){
        return this.get(key).toString().isEmpty()?"null":"not null";
    }
}