java2实用教程(第2版)程序代码.doc

Java 语言入门 例子1 public class Hello { public static void main (String args[ ]) { System.out.println(你好，很高兴学习Java); } } 例子2 public class people { float hight,weight; String head, ear, mouth; void speak(String s) { System.out.println(s); } } class A { public static void main(String args[]) {people zhubajie; zhubajie=new people(); zhubajie.weight=200f; zhubajie.hight=1.70F; zhubajie.head=“大头”; zhubajie.ear=两只大耳朵; zhubajie.mouth=一只大嘴; System.out.println(重量+zhubajie.weight+身高 +zhubajie.hight); System.out.println(zhubajie.head+zhubajie.mouth+zhubajie.ear); zhubajie.speak(师傅， } } 例子3 import java.applet.*; import java.awt.*; public class boy extends Applet { public void paint(Graphics g) { g.setColor(Color.red); g.drawString(我一边喝着咖啡，一边学Java呢,2,30); g.setColor(Color.blue); g.drawString(我学得很认真,10,50); } } 标识符、关键字和数据类型 例子1 public class Example2_1 { public static void main (String args[ ]) { char chinaWord=你,japanWord=ぁ; int p1=20328,p2=12358; System.out.println(汉字\你\字在unicode表中的顺序位置:+(int)chinaWord); System.out.println(日语\ぁ\字在unicode表中的顺序位置:+(int)japanWord); System.out.println(unicode表中第20328位置上的字符是:+(char)p1); System.out.println(unicode表中第12358位置上的字符是:+(char)p2); } } 例子2 public class Example2_2 { public static void main (String args[ ]) { byte a=120; short b=255; int c=2200; long d=8000; float f; double g=123456789.123456789; b=a; c=(int)d; f=(float)g; //导致精度的损失. System.out.print(a= +a); System.out.println( b= +b); System.out.print(c= +c); System.out.println( d= +d); System.out.println(f= +f); System.out.println(g= +g); } } 运算符、表达式和语句 例子1 class Example3_1 { public static void main(String args[]) {char a1=十,a2=点,a3=进,a4=攻; char secret=8; a1=(char)(a1^secret); a2=(char)(a2^secret); a3=(char)(a3^se