public class HelloWorld {
/* 第一个Java程序
* 它将输出字符串 Hello World
*/
public static void main(String[] args) {
System.out.println("Hello World"); // 输出 Hello World
}
}
class FreshJuice {
enum FreshJuiceSize{ SMALL, MEDIUM , LARGE }
FreshJuiceSize size;
}
public class FreshJuiceTest {
public static void main(String[] args){
FreshJuice juice = new FreshJuice();
juice.size = FreshJuice.FreshJuiceSize.MEDIUM ;
}
}
1 public class Puppy{
2 int puppyAge;
3 public Puppy(String name){
4 // 这个构造器仅有一个参数:name
5 System.out.println("小狗的名字是 : " + name );
6 }
7
8 public void setAge( int age ){
9 puppyAge = age;
10 }
11
12 public int getAge( ){
13 System.out.println("小狗的年龄为 : " + puppyAge );
14 return puppyAge;
15 }
16
17 public static void main(String[] args){
18 /* 创建对象 */
19 Puppy myPuppy = new Puppy( "tommy" );
20 /* 通过方法来设定age */
21 myPuppy.setAge( 2 );
22 /* 调用另一个方法获取age */
23 myPuppy.getAge( );
24 /*你也可以像下面这样访问成员变量 */
25 System.out.println("变量值 : " + myPuppy.puppyAge );
26 }
27 }
1 import java.io.*;
2
3 public class Employee{
4 String name;
5 int age;
6 String designation;
7 double salary;
8 // Employee 类的构造器
9 public Employee(String name){
10 this.name = name;
11 }
12 // 设置age的值
13 public void empAge(int empAge){
14 age = empAge;
15 }
16 /* 设置designation的值*/
17 public void empDesignation(String empDesig){
18 designation = empDesig;
19 }
20 /* 设置salary的值*/
21 public void empSalary(double empSalary){
22 salary = empSalary;
23 }
24 /* 打印信息 */
25 public void printEmployee(){
26 System.out.println("名字:"+ name );
27 System.out.println("年龄:" + age );
28 System.out.println("职位:" + designation );
29 System.out.println("薪水:" + salary);
30 }
31 }
1 import java.io.*;
2 public class EmployeeTest{
3
4 public static void main(String[] args){
5 /* 使用构造器创建两个对象 */
6 Employee empOne = new Employee("RUNOOB1");
7 Employee empTwo = new Employee("RUNOOB2");
8
9 // 调用这两个对象的成员方法
10 empOne.empAge(26);
11 empOne.empDesignation("高级程序员");
12 empOne.empSalary(1000);
13 empOne.printEmployee();
14
15 empTwo.empAge(21);
16 empTwo.empDesignation("菜鸟程序员");
17 empTwo.empSalary(500);
18 empTwo.printEmployee();
19 }
20 }