java实验总结

1. 设计一个Person类，包含：姓名，年龄，性别。要求：该类至多只能创建一男、一女两个对象。

2. 设计一个测试类Test，创建若干个Person类对象，测试是否符合要求。

package test8;

class person {

String name;

int age;

char sex;

static int flag1 = 1, flag2 = 1;

private person(String n, int a, char s) {

name = n;

age = a;

sex = s;

if (s == 'm') {

flag1--;

}

if (s == 'f') {

flag2--;

}

}

public static person newperson(String n, int a, char s) {

if (s == 'm' && flag1 != 0) {

person p = new person(n, a, s);

return p;

} else if (s == 'f' && flag2 != 0) {

person p = new person(n, a, s);

return p;

} else {

return null;

}

}

public String toString() {

return ("name:" + name + " age:" + age + " sex:" + sex);

}

}

public class test {

public static void main(String[] args) {

person p1 , p2 , p3 ;

p1= person.newperson("mary", 11, 'f');

p2=person.newperson("tom", 14, 'm');

p3=person.newperson("jane", 13, 'f');

System.out.println(p1);

System.out.println(p2);

System.out.println(p3);

}

}

1. 设计一个数据单元类DataUnit, 它包含学号(Number)和姓名(Name)两个数据成员。

2. 设计两个线程，一个线程往数据单元里写信息，一个线程从数据单元里读信息。要求使用线程同步技术，使得每写一次就往外读一次。例如，写和读的数据序列为：

Write: 1, Name1

Read: 1, Name1

Write: 2, Name2

Read: 2, Name2

...

package test7;

class DataUnit{

int number;

String name;

int max;

boolean flag=false;

public DataUnit(int number, String name,int max){

this.name=name;

this.max=max;

}

public synchronized void in(){

if(flag){

try{

wait();

}

catch(Exception e){

}

}

System.out.println("Write number:"+(++number)+" write name:"+(number));

flag=true;

notify();

}

public synchronized void out(){

if(!flag){

try{

wait();

}

catch(Exception e){

}

}

System.out.println("read number:"+(number)+" read name:"+(number));

flag=false;

notify();

}

}

class write extends Thread{

DataUnit x=null;

public write(DataUnit x){

this.x=x;

}

public void run(){

while(x.number

x.in();

}

}

}

class read extends Thread{

DataUnit x=null;

public read(DataUnit x){

this.x=x;

}

public void run(){

while(x.number<=x.max){

x.out();

}

}

}

public class test7 {

public static void main(String[] args) {

DataUnit x=new DataUnit(0,"mary",10);

new write(x).start();

new read(x).start();

}

}

设计一个线程Thread类的子类DataThread, 使用DataThread构建两个线程，分别输出50以内的奇数和偶数，并使两个线程并发执行。

package test6;

class datathread extends Thread{

private int number;

String flag;

public datathread(int num){

number=num;

if(number==-2)

flag="even";

else

flag="odd";

}

public void run(){

int result=number;

System.out.println("thread "+flag+" starts!");

while(result+2<=50){

result=result+2;

System.out.println("an "+flag+" number:"+result);

}

System.out.println("thread "+flag+" ends!");

}

}

public class Main {

public static void main(String[] args) {

System.out.println("main thread starts!");

datathread thread1=new datathread (-2);

datathread thread2=new datathread (-1);

thread1.start();

thread2.start();

System.out.println("main thread ends!");

}

}

1. 设计一个学生Student类，包含学号(Sno),姓名(Name),所在系(Dept)等属性。创建若干Student类的对象，添加到一个向量Vector中，并遍历输出该向量各元素值。

package test5;

import java.util.*;

public class Student {

String sno;

String name;

String dept;

public Student(String no,String n,String p){

this.sno=no;

this.name=n;

this.dept=p;

}

public String toString(){

return("sno:"+sno+" name:"+name+" dept:"+dept);

}

public static void main(String[] args) {

Student stu[];

stu=new Student[3];

stu[0]=new Student("001","Mary","SS");

stu[1]=new Student("002","Tom","CS");

stu[2]=new Student("003","Hellen","IS");

Vector v=new Vector();

for(int i=0;i

v.add(stu[i]);

}

Iteratornum=v.iterator();

while(num.hasNext()){

System.out.println(num.next());

}

}

}

2. 已知：哈希表HashTable hTable = new HashTable()。编程遍历hTable，要求写出两种方式。

package test5hash;

import java.util.*;

import java.lang.Iterable;

public class Hash {

public static void main(String[] args) {

Hashtable hTable = new Hashtable();

hTable.put(001, "a");

hTable.put(002, "b");

hTable.put(003, "c");

Iterator i = (Iterator)hTable.keys();

while(i.hasNext())

{

int j = i.next();

System.out.print(j+" ");

System.out.println(hTable.get(j));

}

System.out.print(key+" ");

System.out.println( hTable.get(key));

}

}

}

1. 创建一学生类（包括：姓名、年龄、所在班级、密码），创建若干该类的对象并保存到文件a.dat中（密码不用保存），从文件a.dat读取对象显示在屏幕上。

package student;

import java.io.*;

class Student implements Serializable{

String name;

int age;

int Sclass;

transient String password;

public Student(String n,int a,int sc,String p){

this.name=n;

this.age=a;

this.Sclass=sc;

this.password=p;

}

}

public class Main {

public static void main(String[] args) throws IOException ,ClassNotFoundException{

Student stu[];

stu=new Student[3];

stu[0]=new Student("Mary",14,1,"123");

stu[1]=new Student("Tom",14,2,"145");

stu[2]=new Student("Jim",16,2,"456");

ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("D:/a.dat"));

for(int i=0;i<3;i++){

oos.writeObject(stu[i]);

stu[i]=null;

}

oos.close();

ObjectInputStream ois=new ObjectInputStream(new FileInputStream("D:/a.dat"));

for(int i=0;i

stu[i]=(Student) ois.readObject();

}

ois.close();

for(int i=0;i<3;i++){

System.out.println("name:"+stu[i].name+" age:"+stu[i].age+" class"+stu[i].Sclass);

}

}

}

1. 模仿文本文件复制的程序，编写对二进制文件进行复制的程序。

package filecopy;

import java.io.*;

class Copyer{

String sourcename,destname;

DataInputStream source;

DataOutputStream dest;

int data;

private boolean openfiles(){

try{

source=new DataInputStream(new FileInputStream(sourcename) );

}

catch(IOException iox){

System.out.println("problem opening"+sourcename);

return false;

}

try{

dest=new DataOutputStream(new FileOutputStream(destname) );

}

catch(IOException iox){

System.out.println("problem opening"+destname);

return false;

}

return true;

}

private boolean copyf(){

try{

while((data=source.read())!=-1)

dest.writeInt(data);

}

catch(IOException iox){

System.out.println("problem reading or writing");

return false;

}

return true;

}

private boolean closef(){

boolean retval=true;

try{

source.close();

dest.close();

}

catch(IOException iox){

System.out.println("problem closing");

retval=false;

}

return retval;

}

public boolean copy(String src,String dst){

sourcename=src;

destname=dst;

return openfiles()&©f()&&closef();

}

}

public class main {

public static void main(String[] args) {

if(args.length==2){

new Copyer().copy("d:\\a.txt","d:\\b.txt");

}

else{

System.out.println("please enter file name");

}

}

}

2. 创建一个存储若干随机整数的文本文件。其中文件名、整数的个数及其范围均由键盘输入。

package creatfile;

import java.io.*;

import java.util.*;

public class Main

{

private String name;

private int count;

private int Max;

private int Min;

public Main(String n, int c, int max, int min)

{

this.name = n;

this.count = c;

this.Max = max;

this.Min = min;

}

public void createfile()

{

try

{

FileWriter creat = new FileWriter(name);

int limit = Max - Min;

Random random = new Random();

for (int i = 1; i <= count; i++)

{

int number = Min + random.nextInt(limit);

System.out.print(number);

System.out.print(" ");

creat.write(number + " ");

}

creat.close();

}

catch (IOException iox)

{

System.out.println("Error!");

}

}

public static void main(String[] args) throws IOException

{

String filename;

int count, min, max;

Scanner in = new Scanner(System.in);

System.out.println("请输入文件名");

filename = in.next();

System.out.println("输入随机数的个数");

count = in.nextInt();

System.out.println("输入随机数的最小值");

min = in.nextInt();

System.out.println("输入随机数的最大值");

max = in.nextInt();

Main M = new Main(filename, count, max, min);

M.createfile();

}

}

1. 编写求解几何图形（如直线、矩型，圆形）的周长和面积的应用程序，

要求使用接口实现多重继承和多态技术。

提示：声明Iperimeter和IArea分别表示周长接口和面积接口；声明抽象类Shape.

package test3;

interface Iperimeter{

public double imperimeter();

}

interface IArea{

public double IArea();

}

abstract class shape implements IArea,Iperimeter{

public abstract double imperimeter();

public abstract double IArea();

}

class rectangle extends shape{

double length,width;

public rectangle(double x,double y){

length=x;

width=y;

}

public double imperimeter(){

return (length+width)*2;

}

public double IArea(){

return length*width;

}

}

class circle extends shape{

static double pi=3.14;

int r;

public circle(int r0){

r=r0;

}

public double imperimeter(){

return 2*pi*r;

}

public double IArea(){

return pi*r*r;

}

}

public class test {

public static void main(String[] args) {

shape s1=new rectangle(2,3);

shape s2=new circle(3);

System.out.println("the imperimeter of s1 is:"+s1.imperimeter()+"\nthe arae of s1 is:"+s1.IArea());

System.out.println("the imperimeter of s2 is:"+s2.imperimeter()+"\nthe arae of s2 is:"+s2.IArea());

}

}

1. 定义一个接口EqualDiag，表示具有等斜边的图形对象，其中包含：

a. 方法getDiag，用来计算图形的斜边的长度;

b. 方法getArea，用来计算图形的面积;

c. 方法compareTo, 用来比较两个对象的大小(按照斜边的大小进行比较);

2. 定义一个矩形类Rectangle，再派生一个正方形类Square:

a. 在矩形类和正方形类中实现接口EqualDiag;

package test2;

import java.lang.Math.*;

interface EqualDiag

{

public double getDiag();

public double getArea();

public int compareTo(Object a);

}

class Rectangle implements EqualDiag

{

double length;

double width;

public void setlength(double m)

{

length = m;

}

public void setwidth(double n)

{

width = n;

}

public double getDiag()

{

return Math.sqrt(width * width + length * length);

}

public double getArea()

{

return length * width;

}

public int compareTo(Object a)

{

Rectangle x;

x = (Rectangle)a;

if (this.getDiag() > x.getDiag())

return 1;

else if (this.getDiag() == x.getDiag())

return 0;

else return -1;

}

}

class Square extends Rectangle

{

public void setlength(double m)

{

length = m;

width = m;

}

}

public class test

{

public static void main(String[] args)

{

Rectangle a = new Rectangle();

Rectangle b = new Rectangle();

a.setlength(5);

a.setwidth(4);

b.setlength(3);

b.setwidth(4);

System.out.println("矩形a的对角线长为：" + a.getDiag() + "\n矩形a的面积为：" + a.getArea() + "\n矩形b的对角线长为：" + b.getDiag() + "\n矩形b的面积为：" + b.getArea());

System.out.println("矩形a,b比较结果：" + a.compareTo(b));

Square c = new Square();

Square d = new Square();

c.setlength(5);

d.setlength(3);

System.out.println("正方形c的对角线长为：" + c.getDiag() + "\n正方形c的面积为：" + c.getArea() + "\n正方形d的对角线长为：" + d.getDiag() + "\n正方形d的面积为：" + d.getArea());

System.out.println("正方形c,d比较结果：" + c.compareTo(d));

}

}

1. 声明一个抽象类comparable, 用于对两个不同对象的比较，并满足：

a) 包含一个抽象方法int compareTo(comparable b); 若小于对象b则返回-1,大于则返回1,相等则返回0.

b) 声明两个子类，一个为复数类complex，另一个为矩形类rect; 在子类中分别实现父类comparable的抽象方法.

c) 复数类的大小比较以模为基准，而矩形类的比较以面积为基准。

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package test1;

import java.lang.Math.*;

/**

*

* @author Administrator

*/

abstract class comparable{

public abstract int compareTo(comparable b);

}

class rectangle extends comparable{

int length;

int width;

public void setlength(int len){

length=len;

}

public void setwidth(int wid){

width=wid;

}

public int compareTo(comparable b){

rectangle a=(rectangle)b;

if(this.length*this.width>a.length*a.width)

return 1;

if(this.length*this.width==a.length*a.width)

return 0;

else return -1;

}

}

class complex extends comparable{

double real;

double imaginary;

public void setreal(double nreal){

real=nreal;

}

public void setimaginary(double nimaginary){

imaginary=nimaginary;

}

public double Mo(){

return Math.sqrt(this.real*this.real+this.imaginary*this.imaginary);

}

public int compareTo(comparable b){

complex a=(complex)b;

if(this.Mo()>a.Mo())

return 1;

if(this.Mo()==a.Mo())

return 0;

else return -1;

}

}

public class test {

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

// TODO code application logic here

rectangle x=new rectangle ();

rectangle y=new rectangle ();

x.setlength(4);

x.setwidth(6);

y.setlength(6);

y.setwidth(4);

System.out.println(x.compareTo(y));

complex m=new complex();

complex n=new complex();

m.setreal(6);

m.setimaginary(5);

n.setreal(5);

n.setimaginary(3);

System.out.println(m.compareTo(n));

}

}

1. 编写一个矩形类rectangle：

a. 成员变量包括：长和宽；

b. 方法包括：计算面积、计算周长、设置长和宽的值（从键盘输入）；

c. 重写toString()方法，显示rectangle对象的详细信息；

d. 重写equals方法，如果两个矩形的面积和周长都相等，则认为它们是同一。

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package rectangle;

import java.util.*;

/**

*

* @author Administrator

*/

public class rectangle {

int width,height;

Scanner input;

public void set(){

input=new Scanner(System.in);

width=input.nextInt();

height=input.nextInt();

}

public int Setarea(){

return height*width;

}

public int Setcircumference(){

return (height+width)*2;

}

public String toString(){

return("?╁舰?夸负锛?+width+"\n?╁舰瀹戒负锛?+height+"\n?╁舰?㈢Н涓猴?"+height*width+"\n?╁舰?ㄩ?夸负锛?"+(height+width)*2);

}

@Override

public boolean equals(Object x){

if(this.getClass()!=x.getClass())

return false;

rectangle y=(rectangle)x;

return ((this.Setarea()==y.Setarea())&&(this.Setcircumference()==(y.Setcircumference())));

}

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

// TODO code application logic here

rectangle a=new rectangle();

rectangle b=new rectangle();

a.set();

b.set();

a.equals(b);

System.out.println(a);

System.out.println(b);

System.out.println(a.equals(b));

}

}

1. 声明一个person类，包含：

a) 属性：姓名，年龄，性别；

b) 方法：设置person信息，显示person信息(重写toString方法)；

2. 声明一个student类，作为person类的子类。包含：

a) 属性：学号，英语成绩，数学成绩，物理成绩，平均成绩，总成绩；

b) 方法：设置学号，设置各科成绩，计算平均成绩，计算总成绩，显示student信息(重写toString方法)；

3. 声明一个测试类test, 生成若干个student类的对象，分别计算他们的各项成绩，并输出其信息。

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package test;

/**

*

* @author Administrator

*/

class person{

String name;

int age;

char sex;

void setname(String Nname){

name=Nname;

}

void setage( int Nage){

age=Nage;

}

void setsex(char Nsex){

sex=Nsex;

}

public String toString(){

return("name:"+name+"\nage:"+age+"\nsex"+sex);

}

}

class student extends person{

int number;

int englishscore;

int mathscore;

int physicsscore;

int averagescore;

int totalscore;

void setnumber(int num){

number=num;

}

void setEscore(int english){

englishscore=english;

}

void setMscore(int math){

mathscore=math;

}

void setPscore(int physics){

physicsscore=physics;

}

int countaverage(){

return((englishscore+mathscore+physicsscore)/3);

}

int counttotal(){

return(englishscore+mathscore+physicsscore);

}

public String toString(){

return("name:"+name+"\nage:"+age+"\nsex:"+sex+"\nnumber:"+number+"\nEnglish:"+englishscore+"\nMath:"+mathscore+"\nPhysics:"+physicsscore+"\nAveragescore:"+averagescore+"\nTotalscore:"+totalscore);

}

}

public class test {

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

student a=new student();

student b=new student();

a.setname("mary");

a.setage(11);

a.setsex('f');

a.setnumber(000);

a.setEscore(90);

a.setMscore(88);

a.setPscore(80);

a.averagescore=a.countaverage();

a.totalscore=a.counttotal();

b.setname("bob");

b.setage(12);

b.setsex('m');

b.setnumber(001);

b.setEscore(91);

b.setMscore(86);

b.setPscore(79);

b.averagescore=b.countaverage();

b.totalscore=b.counttotal();

System.out.println(a);

System.out.println(b);

// TODO code application logic here

}

}

1．定义一个Point类。该类具有以下特点：

a. int型变量x,y表示屏幕坐标系上的一个点;

b. 两种构造方法实现对象的初始化：Point(int x, int y)和Point(Point p);

c. 计算两个Point对象之间距离的方法distance(Point a, Point b);

d. 获得当前坐标x,y值的方法getX(),getY();

e. 设置坐标x,y值的方法setX(),setY();

f. 重写Point类的toString()方法，以格式(x,y)输出当前点的字符串;

g. 统计应用程序中Point类对象的个数（使用Point类的类变量）。

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package point;

/**

*

* @author Administrator

*/

public class app {

static int count;

int x;

int y;

public app(int x1,int y1){

x=x1;

y=y1;

count++;

}

public app(app p1){

x=p1.x;

y=p1.y;

count++;

}

public double distance(app a,app b,double d){

d=Math.sqrt(((a.x-b.x)*(a.x-b.x))+((a.y-b.y)*(a.y-b.y)));

return d;

}

public int getX(){

return x;

}

public int getY(){

return y;

}

public void setX(int x1){

x=x1;

}

public void setY(int y1){

y=y1;

}

public String toString(){

return("("+x+","+y+")");

}

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

app a=new app(0,0);

app b=new app(a.x,a.y);

int d=0;

int m,n,p,q;

a.setX(2);

a.setY(5);

b.setX(1);

b.setY(1);

m=a.getX();

n=a.getY();

p=b.getX();

q=b.getY();

System.out.println("m="+m+"\nn="+n+"\np="+p+"\nq="+q);

System.out.println("the distance is:"+a.distance(a,b,d));

System.out.println("here is the cordinate:"+a);

System.out.println("here is the cordinate:"+b);

System.out.println("the number of the objects is:"+count);

// TODO code application logic here

}

}

1. 设计一个复数类complex，包括：

a. 成员变量：复数的实部和虚部;

b. 构造函数：带参数和不带参数的构造函数，对成员变量进行初始化；

c. 成员方法：复数的加、减、乘运算。

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package complex;

/**

*

* @author Administrator

*/

public class app {

int real;

int imaginary;

public app(){

real=0;

imaginary=0;

}

public app(int initreal,int initimaginary){

real=initreal;

imaginary=initimaginary;

}

public app add(app number1,app number2){

number1.real=number1.real+number2.real;

number1.imaginary=number1.imaginary+number2.imaginary;

return number1;

}

public app minus(app number1,app number2){

number1.real=number1.real-number2.real;

number1.imaginary=number1.imaginary-number2.imaginary;

return number1;

}

public app multiply(app number1,app number2,app num){

num.real=number1.real*number2.real-number1.imaginary*number2.imaginary;

num.imaginary=number1.real*number2.imaginary+number1.imaginary*number2.real;

return num;

}

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

// TODO code application logic here

app number1;

number1=new app(5,7);

app number2;

number2=new app(6,8);

app num;

num=new app(0,0);

System.out.println("the adding result is:"+number1.add(number1, number2).real+"+"+number1.imaginary+"i");

number1=new app(5,7);

System.out.println("the minus result is:"+number1.minus(number1, number2).real+"+("+number1.imaginary+")i");

number1=new app(5,7);

System.out.println("the multify result is:"+num.multiply(number1, number2,num).real+"+"+num.imaginary+"i");

}

}

1. 使用数组编程，按下列格式输出数字：

1 3 6 10 15

2 5 9 14

4 8 13

7 12

11

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package array;

/**

*

* @author Administrator

*/

public class app {

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

int myArray[][];

int m=4;

myArray=new int[5][5];// TODO code application logic here

myArray[0][0]=1;

for(int i=1;i

myArray[0][i]=myArray[0][i-1]+i+1;

for(int i=0;i

System.out.printf("%3d",myArray[0][i]);

System.out.print("\n");

for(int i=1;i

{ for(int j=0;j

{myArray[i][j]=myArray[0][j+i-1]+j+1;

System.out.printf("%3d",myArray[i][j]);

}

System.out.print("\n");

m--;

}

}

}

2. 定义一个学生类(Student)，属性有private的名字(name), public的年龄(age);

设置name和age属性的方法：setName(),getName(); setAge(),getAge(),以及显示name和age值的方法showName(),showAge();

编写Application，创建一个学生对象，设置name和age属性值，并显示name和age.

/*

* To change this template, choose Tools | Templates

* and open the template in the editor.

*/

package classpkg;

/**

*

* @author Administrator

*/

public class Main {

private String name;

public int age;

/**

* @param args the command line arguments

*/

public void setName(String newN) {

name=newN;

// TODO code application logic here

}

public void setAge(int newA) {

age=newA;

// TODO code application logic here

}

public String getName() {

return name;

// TODO code application logic here

}

public int getAge() {

return age;

// TODO code application logic here

}

public void showName() {

System.out.println(name);

// TODO code application logic here

}

public void showAge() {

System.out.println(age);

// TODO code application logic here

}

public static void main(String[] args) {

Main x;

String m;

x=new Main();

x.setName("bn");

x.setAge(11);

m=x.getName();

x.getAge();

x.showName();

x.showAge();

System.out.println(m);

// TODO code application logic here

}

// TODO code application logic here

}