举一反三
- class Person{ static{ System.out.println(name); } private static String name = "hello"; } class Demo{ public static void main(String[] args){ Person p = null; } }
- 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 ; } }
- 阅读下面代码： Person 类： public class Person { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } } Servlet1: request.getSession().setAttribute("name","zhangsan"); Person p = new Person(); p.setName("lisi"); request.getSession().setAttribute("person",p); Servlet2: String name1 = (String)request.getSession().getAttribute("name"); Person p = (Person)request.getSession().getAttribute("person"); response.getWriter().write(name1); if(p!=null)response.getWriter().write(p.getName()); 浏览器先访问Servlet1，再去访问Servlet2，输出的结果是：（）
- 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)； }}
- 下列程序的运行结果是（ ）class Demo{private String name;Demo(String name){this.name = name;}private static void show(){System.out.println(name)}public static void main(String[] args){Demo d = new Demo(“lisa”);d.show();}}
内容
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【填空题】public class ThisTest{ private String name; private int age; public ThisTest() { System.out.println("产生一个新的Person对象。"); } public ThisTest (String name, int age) { this(); this.name = name; this.age = age; } public String getInf() { return "姓名:" + name + ",年龄:" + age; } public static void main(String[] args) { ThisTest per = new ThisTest("张三", 20); System.out.println(per.getInf()); } } 运行结果为:____
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import java.io.*; class Person{ public void print(){System.out.print("Person ");} public void printMyGender(String s){ this.print(); System.out.print(s+" "); } } class Gender{ String type="gender"; public void print(Person p){p.printMyGender(type);} } class Female extends Gender{ public Female(){ type="female"; } } class Male extends Gender{ public Male(){ type="male"; } } class Employee extends Person{ public void print(){ System.out.print("Employee ");} } class Manager extends Employee{ public void print(){ System.out.print("Manager ");} } public class Test{ public static void main(String[] args){ Manager man = new Manager(); Employee em = new Employee(); Gender gender1 = new Male(); Gender gender2 = new Female(); gender1.print(man); gender2.print(em); } } 对于以上代码，其运行结果是
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（6-9）定义了如下Person类，下面程序段能够正确初始化Person数组。 class Person{ private String name; public Person(String name){ this.name=name; } }
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（6-2）定义如下Person类，(1)处合理的代码是。 class Person { String name, department; int age; public Person(String n) { name = n; } public Person(String n, int a) { name = n; age = a; } public Person(String n, int a, String d) { ① department = d; } }
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class Person { String name; int age; [br][/br] public Person(String name, int age) { super(); this.name = name; this.age = age; } @Override public boolean equals(Object obj) { Person person=null; if(obj instanceof Person) person=(Person)obj; if(name.equals(person.name)&&age==person.age) return true; return false; } } class Test{ public static void main(String[] args) { Person person1 = new Person("张三", 12); Person person2 = new Person("张三", 12); System.out.println(person1.equals(person2));//运行结果是？ } } 程序运行结果是什么？ A: true B: false