Java期末考最新试卷

程序1.TestIo2.AWT 布局监听控件====稍后再看3.类（略）4.编译和运行JAVAE:Cd javabao 文件夹Javac java.java 编译Java java 运行5.JAVA 解析器加载类6.实例变量静态变量实例变量:类的内部，方法外部定义的变量，在各对象中各有一个副本静态变量：有static修饰的，各个对象独享一个静态变量，不需要实例化public class Cat {private static int sid = 0;private String name;int id;Cat(String name) {s id++; = name;id = sid;}public void info(){System.out.println("My name is "+name+" No."+id); }public static void main(String arg[]){Cat.sid = 100;Cat mimi = new Cat("mimi");Cat pipi = new Cat("pipi");();();}}=============================My name is mimi No.101My name is pipi No.2001==============================7.重载class Person {//成员变量定义private int id;private int age = 20;Person() {id = 0;age = 20;}Person(int _id) {id = _id;age = 23;}Person(int _id, int _age) {id = _id;age = _age;}void info() {System.out.println("my id is: " + id +" "+"age is" + age); }}public class TestOverLoad {public static void main(String[] args) {Person p = new Person();Person p1 = new Person(400);Person p2 = new Person(2, 500);();();();}}===========================my id is: 0 age is20my id is: 400 age is23my id is: 2 age is500===========================8.Super 和thisThis指的是当前对象Super 指向的是父类class FatherClass {public int value;public void f(){value = 100;System.out.println("FatherClass.value="+value);}}class ChildClass extends FatherClass { public int value;public void f() {super.f();value = 200;System.out.println("ChildClass.value="+value);System.out.println(value);System.out.println(super.value);}}public class TestInherit {public static void main(String[] args) { ChildClass cc = new ChildClass();cc.f();}}==============================FatherClass.value=100ChildClass.value=200200100============================9..继承中的构造方法class SuperClass {private int n;SuperClass() {System.out.println("SuperClass()"); }SuperClass(int n) {this.n = n;System.out.println("SuperClass(" + n + ")");}}class SubClass extends SuperClass {private int n;SubClass(int n) {//super();this.n = n;System.out.println("SubClass(" + n + ")");}SubClass() {super(300);System.out.println("SubClass()");}}public class TestSuperSub {public static void main(String arg[]) {SubClass sc1 = new SubClass();SubClass sc2 = new SubClass(400);}}=================SuperClass(300)SubClass()SuperClass()SubClass(400)===================10抽象类11.接口Final12多态class Animal {public void enjoy(){System.out.println("叫声......");}}class CatCat extends Animal {public void enjoy() {System.out.println("猫叫声......");}}class Dog extends Animal {public void enjoy() {System.out.println("狗叫声......");}}class Bird extends Animal {public void enjoy() {System.out.println("鸟叫声......");}}class Lady {private String name;private Animal pet;Lady(String name,Animal pet) { = name;this.pet = pet;}public void myPetEnjoy(){p et.enjoy();}}public class Test {public static void main(String args[]){C atCat c = new CatCat();Dog d = new Dog();Bird b = new Bird();Lady l1 = new Lady("l1",c); Lady l2 = new Lady("l2",d); Lady l3 = new Lady("l3",b);l1.myPetEnjoy();l2.myPetEnjoy();l3.myPetEnjoy();}}=================猫叫声......狗叫声......鸟叫声......==================13.用到的包14.string //stringbuffer书本P140==================================大题目15.awtimport java.awt.*;import java.awt.event.*;import java.applet.*;public class TFMath {public static void main(String[] args) {new TFFrame().launchFrame();}}class TFFrame extends Applet {Frame f = new Frame();TextField num1, num2, num3;public void launchFrame() {num1 = new TextField(10);num2 = new TextField(10);num3 = new TextField(15);Label lblPlus = new Label("+");Button btnEqual = new Button("=");btnEqual.addActionListener(new MyMonitor());f.setLayout(new FlowLayout());f.add(num1);f.add(lblPlus);f.add(num2);f.add(btnEqual);f.add(num3);f.pack();f.setVisible(true);}private class MyMonitor implements ActionListener { public void actionPerformed(ActionEvent e) {int n1 = Integer.parseInt(num1.getText());int n2 = Integer.parseInt(num2.getText());num3.setText("" + (n1+n2));}}}注意：在HTML中的嵌套使用//输出101~200内的质数public class TestZ {public static void main(String[] args){ for(int i=101; i<200; i++){boolean f = true;for(int j=2; j<i; j++){if(i%j==0){f = false;break;}}if(!f){continue;}System.out.print(i+" ");}}}//排序int[] arr = {2,4,6,7,3,5,1,9,8};for(int i=0 ; i<arr.length ; i++){for(int j=i+1 ; j<arr.length ; j++){if(arr[i]<arr[j]){int temp = arr[i];arr[i] = arr[j];arr[j] = temp;}}System.out.print(arr[i] +" ");}//9 8 7 6 5 4 3 2 1============================大题目 testIOimport java.io.*;public class TestIo {public static void copy1(){int i = 0;InputStreamReader fr = null;OutputStreamWriter fw = null;try {fr = new InputStreamReader(newFileInputStream("C:\\Users\\xiao he shang\\Desktop\\file\\java.txt"));fw = new OutputStreamWriter(newFileOutputStream("C:\\Users\\xiao heshang\\Desktop\\file\\java2.txt"));while((i = fr.read())!= -1){fw.write((char)i);}fr.close();fw.close();} catch (IOException e) {e.printStackTrace();}}555 public static void copy2(){String s = null;try {BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("C:\\Users\\xiao he shang\\Desktop\\file\\java.txt")));BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(newFileOutputStream("C:\\Users\\xiao heshang\\Desktop\\file\\java3.txt")));while( (s = br.readLine())!= null){bw.write(s);}br.close();bw.close();} catch (IOException e) {e.printStackTrace();}}public static void copy3(){String s = null;try {BufferedReader br = new BufferedReader(new InputStreamReader(System.in));BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("C:\\Users\\xiao heshang\\Desktop\\file\\java4.txt")));while( (s = br.readLine())!= null){if(s.equalsIgnoreCase("exit")){break;}bw.write(s);}br.close();bw.close();} catch (IOException e) {e.printStackTrace();}}public static void main(String[] args) {copy1();copy2();copy3();}}。