com.datastax.data.dataset.DataConnection Maven / Gradle / Ivy

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package com.datastax.data.dataset;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.logging.Level;
import java.util.logging.Logger;


public abstract class DataConnection {
    
    private static final Logger LOG = Logger.getLogger(DataConnection.class.getName());

    
    private PropertyChangeSupport pcs = new PropertyChangeSupport(this);

    
    private boolean connected = false;
    
    
    public void setConnected(boolean b) {
        if (b && !connected) {
            try {
            	LOG.fine("Attempting to connect to the data store");
                connect();
                connected = true;
                LOG.fine("Connected to the data store, firing property change event");
                pcs.firePropertyChange("connected", false, true);
            } catch (Exception e) {
            	LOG.log(Level.SEVERE, "Failed to connect to the data store.", e);
            	
            	
                connected = false;
            }
        } else if (!b && connected) {
            try {
            	LOG.fine("Attempting to disconnect from the data store");
                disconnect();
            } catch (Exception e) {
            	LOG.log(Level.WARNING, "Failed to physically disconnect from the data store, " +
            			"but will continue to logically disconnect from the data store.", e);
            } finally {
                connected = false;
                LOG.fine("Logically disconnected from the data store, firing property change event");
                pcs.firePropertyChange("connected", true, false);
            }
        }
    }
    
    
    public boolean isConnected() {
        return connected;
    }
    
    
    protected abstract void connect() throws Exception;

    
    protected abstract void disconnect() throws Exception;
    
    
    public void addPropertyChangeListener(PropertyChangeListener listener) {
        pcs.addPropertyChangeListener(listener);
    }

   
     public void addPropertyChangeListener(String propertyName,
            PropertyChangeListener listener) {
        pcs.addPropertyChangeListener(propertyName, listener);
    }
    
    
    public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) {
    	pcs.removePropertyChangeListener(propertyName, listener);
    }

}