A Java database class for a friend.

Database.java

package com.zetaworx.proboblyawesome.handler.database;

import java.io.File;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;

import cpw.mods.fml.common.FMLLog;

public class Database {
	private boolean _isRAMOnly = true; //If true, means this database will exist only while application is running and won't save on shutdown.
	private File _dbFile; //File for the database to work with.
	private ArrayList<String> _memory; //Since we are working with String per line anyway...
	
	
	public Database(String filelocation) throws IOException {
		this(new File(filelocation));
	}
	
	public Database(File file) throws IOException {
		this();
		setFile(file);
	}
	
	public Database() {
		_memory = new ArrayList<String>();
	}
	
	public ArrayList<String> getData() {
		return _memory;	
	}
	
	public String getData(int index) {
		return _memory.get(index);
	}
	
	public int addData(String data) throws Exception {
		if (_memory.add(data)){
			return (_memory.size() - 1);
		} else {
			throw new Exception("Failed to add '" + data + "' to database memory.");
		}
	}
	
	public String setData(int index, String data) {
		return _memory.set(index, data);
	}
	
	public String remData(int index) {
		return _memory.remove(index);
	}
	
	public void loadDatabase() throws IOException {
		if (!_isRAMOnly) {
			BufferedReader stream = new BufferedReader(new FileReader(_dbFile));
			String read;
			while ((read = stream.readLine()) != null)
			{
				_memory.add(read);
			}
			stream.close();
		} else {
			//what'd you expect, there is nothing to load from silly.
		}
	}
	
	public void saveDatabase() throws IOException {
		if (!_isRAMOnly) {
			if (_dbFile.exists()) {
				File backup = new File(_dbFile.getAbsolutePath().concat(".bak"));
				if (backup.exists()) backup.delete();
				_dbFile.renameTo(backup);
			}
			BufferedWriter stream = new BufferedWriter(new FileWriter(_dbFile));
			for (String s : _memory) {
				stream.write(s.concat("\n"));
			}
			stream.close();
		} else {
			//nor is there a place to save it to silly...
		}
	}
	
	public void resetDatabase(boolean hard) throws IOException {
		if (hard && !_isRAMOnly) {
			//HARDCORE RESET, nah, but really deletes db and db.bak file's.
			_dbFile.delete();
			(new File(_dbFile.getAbsolutePath().concat(".bak"))).delete();
		}
		_memory.clear();
		if (!hard) loadDatabase(); //We still have somewhere to load from, right?...
	}
	
	public void setFile(File file) throws IOException {
		FMLLog.info("%s\n", file.getAbsolutePath());
		_dbFile = file;
		if (!_dbFile.exists()) _dbFile.createNewFile();
		_isRAMOnly = false;
	}
	
	public File getFile() {
		return _dbFile;
	}
	
	public String getFileLocation(boolean canonical) {
		return _dbFile.getAbsolutePath();
	}
}