package com.nilhcem.fakesmtp.core.exception;
   
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   
   import javax.swing.JOptionPane;
   import javax.swing.SwingUtilities;
   import java.awt.Component;
   
  /**
   * Intercepts every uncaught exception.
   *
   * @author Nilhcem
   * @since 1.1
   * @see <a href="link">http://stuffthathappens.com/blog/2007/10/07/programmers-notebook-uncaught-exception-handlers/</a>;
   */
  public final class UncaughtExceptionHandler implements Thread.UncaughtExceptionHandler {
  
  	private Component parentComponent;
  	private static final Logger LOGGER = LoggerFactory.getLogger(UncaughtExceptionHandler.class);
  
  	/**
  	 * Called when an uncaught exception is thrown. Will display the error message in a dialog box.
  	 *
  	 * @param t the thread where the exception was throws.
  	 * @param e the thrown exception.
  	 */
  	@Override
  	public void uncaughtException(final Thread t, final Throwable e) {
  		try {
  			if (SwingUtilities.isEventDispatchThread()) {
  				showException(t, e);
  			} else {
  				SwingUtilities.invokeLater(new Runnable() {
  					public void run() {
  						showException(t, e);
  					}
  				});
  			}
  		} catch (Exception excpt) {
  			LOGGER.error("", excpt);
  		}
  	}
  
  	/**
  	 * Sets the parent component where an error dialog might be displayed.
  	 *
  	 * @param parentComponent a component where an error dialog might be displayed.
  	 */
  	public void setParentComponent(Component parentComponent) {
  		this.parentComponent = parentComponent;
  	}
  
  	/**
  	 * Displays an error dialog describing the uncaught exception.
  	 *
  	 * @param t the thread where the exception was throws.
  	 * @param e the thrown exception.
  	 */
  	private void showException(Thread t, Throwable e) {
  		LOGGER.error("", e);
  		String msg = String.format("Unexpected problem on thread %s: %s", t.getName(), e.getMessage());
  		JOptionPane.showMessageDialog(parentComponent, msg);
  	}
  }