第一章 计算机、程序和Java概述 课本源代码

//程序清单1-1 Welcome-java public class Welcome { public static void main(String[] args) { //Display message Welcome t java ! to the console System.out.println("Welcome to Java!"); } } //程序清单1-2 welcome1.java public class Welcome1 { public static void main(String[] args) { System.out.println("Programming is fun!"); System.out.println("Fundamentals First"); System.out.println("Problem Driven"); } } //程序清单1-3 ComputeExpression.java public class ComputeExperssion { public static void main(String[] args) { System.out.println((10.5+2*3)/(45-3.5)); } } //程序清单1-4 WelcomeInMessageDialogBox.java /* This application program displays Welcome to Java! * in a message dialog box * 功能：在对话框中输出“welcome to Java!" */ import javax.swing.JOptionPane; public class WelcomeInMessageDialogBox { public static void main(String [] args) { //输出“Welcome to Java” JOptionPane.showMessageDialog(null,"Welcome to Java!"); } }