举一反三
- 已有如下程序: class Person{ private int a; public void change(int m){a=m;} } public class Teacher extends Person { public int b; public static void main(String args[]){ Person p=new Person(); Teacher t=new Teacher(); int i; _____________________ } } 下面划线处填写的语句那些是非法的操作 提示:考查内容包括静态成员,私有成员,继承等知识点
- 在下列程序的划线处应填入的语句是class Person { private int a;}public class Man extends Person{ public int b; public static void main (String arg []){ Person p=new Person(); Man t=new Man(); int i: }} A.i=w; B.i=b C.i=p.a; D.i=t.b;
- class Person {private int a;public int... // point x安排哪个语句合法?
- class Person{} class Student extends Person{ public int id; public int score; public String name; public int getScore() { return score; }
- 分析下面的程序,输出的结果是? public class Test { public static void main(String[] args) { final Person p = new Person("张三", 23); p.setName("李四"); p.setAge(24); System.out.println(p); } } class Person { private String name; private int age; public Person() { super(); } public Person(String name, int age) { super(); this.name = name; this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "我的姓名是:" + name + ",我的年龄是:" + age ; } }
内容
- 0
请写出下列程序的输出结果。class A{public int f(int x) {return x+1;}}class B extends A{public int f(int x){return x*x;}}public class E{public static void main(String args[]){A a=new B();int m=a.f(10);System. out. println(m) ;}}
- 1
在C#中,下列结构或者类定义正确的是(选一项) A: public struct Person{ string name; int age; public void ShowName(){ Console.WriteLine(name); }} B: public struct Person{ string name; int age; public Person(){ Conssole.WriteLine(name); }} C: public class Person{ string name; int age; public Person(){ Conssole.WriteLine(name); }} D: public class Person{ string name; int age; public Person(string name){ Conssole.WriteLine(name); }}
- 2
(7-1)请阅读程序,并写出程序运行结果。 class X{ int getX() { return 5; } } class Y extends X{ int getX() { return 6; } } class T extends X{ int getX() { return 7; } } public class Demo10 { public static void main(String[] args) { X x=new X(); Y y=new Y(); X t=new T(); int sum=x.getX()+y.getX()+t.getX(); System.out.println(sum); } }
- 3
根据下面给出的代码,判断那个叙述是对的?public class Person{static int arr[]=new int[10];public static void main(String a[]){System.out.println(arr[1]);}}
- 4
阅读下面的程序,输出结果是()public class TestDemo{int m=5;public void some(int x){m=x;}public static void main(String args[]) {new Demo().some(7);}}class Demo extends TestDemo{int m=8;public void some(int x) {super.some(x);System.out.println(m);}} A: 5 B: 8 C: 7 D: 编译错误