DstoreConnection.java

import java.io.*;
import java.net.*;
import java.lang.Runnable;
import java.util.List;
import java.util.ArrayList;
import java.util.Map;
import java.util.HashMap;
import java.util.Collection;

public class DstoreConnection {
	protected Socket socket;
	protected BufferedReader reader;
	protected PrintWriter writer;
	
	public DstoreConnection(Socket socket) {
		this.socket = socket;
		reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
		writer = new PrintWriter(socket.getOutputStream());
	}
	
	public String sendAndReceive(String message) {
		synchronized(this) {
			try {
				writer.println(message);
				writer.flush();
			}
			catch(IOException e) {
				e.printStackTrace();
				return "";
			}
			return localReceive();
		}
	}
	
	public String receive() {
		synchronized(this) {
			return localReceive();
		}
	}
	
	protected String localReceive() {
		try {
			String returnMessage = reader.readLine();
			return returnMessage;
		}
		catch(IOException e) {
			e.printStackTrace();
			return "";
		}
	}
}