Here you can find the source of showError(Window parent)
public static void showError(Window parent)
//package com.java2s; //License from project: Open Source License import java.awt.Window; import javax.swing.JOptionPane; public class Main { public static void showError(Window parent) { JOptionPane.showMessageDialog(parent, "The weight values must sum to 1.0!", "Error", JOptionPane.ERROR_MESSAGE); }/*from w w w. ja v a 2s . c om*/ }