期末复习JAVA题

1. 分解质因数 package d2;

import java.util.Scanner;

public class Zys {

public static void main(String[]args){ Scanner sc=new Scanner(System.in); System.out.print(\请输入一个数：\ int a=sc.nextInt(); int n=2;

System.out.println(a+\ while(a>=n){ if(a%n==0){

System.out.print(n+\ a=a/n; }

if(a%n!=0){ n++; } } } }

2. 判断是否是回文数

ackage c2;

import java.util.Scanner;

public class huiwenshu {

public static void main(String[]args){ //System.out.println(\请输入一个数\ Scanner a=new Scanner(System.in); System.out.println(\请输入一个数\ String b=a.nextLine(); boolean c=false; for(int i=0;i

c=false; } else c=true; if(c==true) System.out.println(\是回文数\ }else{

System.out.println(\不是回文数\

} }

}

3. 数组逆序输出

public class sz {

public static void main(String[]args){ int a[]={1,2,3,4,5,6,7,8,9,0}; for(int i=9;i>=0;i--){ System.out.println(a[i]); } } }

4. 水仙花数

public class sxh {

public static void main(String[]args){ int a,b,c; for(int i=100;i<=999;i++){ a=i/10; b=i; c=i/100; if(i==a*a*a+b*b*b+c*c*c) System.out.println(i); } } } 5. 素数

public class Sushu {

public static void main(String[] args){ for(int i=100;i<=200;i++){ boolean b=false; for(int j=2;j<=Math.sqrt(i);j++ ){ if(i%j==0){ b=true;break; } else {b=false;} } if (b==false) System.out.println(i); } } }

6．最大公约数和最小公倍数

import java.util.Scanner; public class Sz { public static void main(String[] args) { int a, b, m; Scanner s = new Scanner(System.in); System.out.print(\键入一个整数： \ a = s.nextInt(); System.out.print(\再键入一个整数： \

b = s.nextInt(); deff cd = new deff(); m = cd.deff(a, b); int n = a * b / m; System.out.println(\最大公约数: \m);

System.out.println(\最小公倍数: \n);

} }

class deff { public int deff(int x, int y) { int t; if (x < y) { t = x; x = y; y = t; } while (y != 0) { if (x == y) return x; else { int k = x % y; x = y; y = k; } } return x; } }

1、题目：一个数如果恰好等于它的因子之和，这个数就称为 \完数 \。例如6=1＋2＋3.编程 找出1000以内的所有完数。 public class shishu {

public static void main(String[] args) { int i;

for (i = 2; i <= 1000; i++) { int sum = 0; for (int j = 1; j <=i/2; j++) { if (i % j == 0) {

// System.out.println(j); sum = sum + j; } }

if (sum == i) {

System.out.println(i); }

}

} }

2. 假如我们在开发一个系统时需要对员工进行建模，员工包含3个属性：姓名、工号以及工资。经理也是员工，除了含有员工的属性外，另外还有一个奖金属性。请使用继承的思想设计出员工类和经理类。要求类中提供必要的方法进行属性访问。

public class manager extends yg{ protected int award;

public static void main(String[]args){ yg a=new yg();

a.setdata(\张晓晓\ a.print();

manager b=new manager();

b.setdata(\黄洋洋\ b.award=20000; b.print();

System.out.println(\奖金\ } }

class yg {

protected String name; protected String num; protected int salary;

void setdata(String xm,String gh,int gz){ name =xm; num=gh; salary=gz; }

public void print(){

System.out.println(\姓名：\ System.out.println(\工号\ System.out.println(\工资\} }

3. 以点类作为基类，从点派生出圆，从圆派生圆柱，设计成员函数输出它们的面积和体积。

package third;

public class Circle extends point{ protected int r;

Circle(int r,int x,int y){ super(x,y); this.r=r; }

public double area(){ return 3.14*r*r; }

package third;

public class Cyliner extends Circle { protected int h;

Cyliner(int h,int x,int y,int r){ super(x,y,r); this.h=h; }

public double volume(){ return area()*h; }

public static void main(String[]args){ Circle a=new Circle(2,2,4); Cyliner b=new Cyliner(2,2,3,4);

System.out.println(\圆的面积是：\ System.out.println(\圆的体积是：\} } }

public class point { protected int x; protected int y; point(){

this.x=0; this.y=0; }

point(int x,int y){ this.x=x; this.y=y; } }

4.定义一个抽象基类Shape，它包含三个抽象方法center()、diameter()、getArea()，从Shape类派生出Square和Circle类，这两个类都用center()计算对象的中心坐标，diameter()计算对象的外界圆直径，getArea()方法计算对象的面积。编写编写应用程序使用Rectangle类和Circle类。 package W1; public abstract class Shape {

abstract void center();

abstract void diameter(); abstract void getArea(); }

package W1;

public class Square extends Shape{ @Override

void center() { }

@Override

void diameter() { } @Override void getArea() { } }

package W1;

public class Circle extends Shape{ @Override void center() { } @Override

void diameter() { } @Override

void getArea() { } }

package W1;

public class Rectangle extends Square{ }

package W1;

public class Test {

public static void main(String[] args) {

Circle c = new Circle(); Square r = new Rectangle(); c.center(); c.diameter();

c.getArea(); r.center(); r.diameter(); r.getArea();

} }

实现一个名为Person的类和它的子类Employee， Manager是Employee的子类，设计一个接口Add用于涨工资，普通员工一次能涨10％，经理能涨20％。

具体要求如下： （1）Person类中的属性有：姓名name（String类型），地址address（String类型）并写出该类的构造方法； （2）Employee类中的属性有：工号ID（String型），工资wage（double类型），工龄（int型），写出该类的构造方法； （3）Manager类中的属性有：级别level（String类型），写出该类的构造方法；

public class person { private String name; private String address;

public person(String name2, String address2) { }

public void Person(String n,String a){ this.setName(n); this.setAddress(a); }

public void setName(String n){ this.name = n; }

public void setAddress(String a){ this.address = a; }

private String getName(){ return this.name; }

private String getAddress(){ return this.address; } }

lass Empolyee extends person{ private int employeeNo; private double pay; private int age; public Empolyee(String name,String address,int empolyeeNO, double pay,int age){ super(name,address);

this.setEmployeeNo(empolyeeNO); this.setPay(pay); this.setAge(age); }

public void setEmployeeNo(int e){ this.employeeNo = e; }

public void setPay(double p){ this.pay = p; }

public void setAge(int a){ this.age = a; }

public int getEmployeeNo(){ return this.employeeNo; }

public double getPay(){ return this.pay; }

public int getAge(){ return this.age; } }

class Manager extends Empolyee{ private int level;

public Manager(String name,String address,int empolyeeNO,double pay, int age,int level){

super(name,address,empolyeeNO,pay,age); this.setLevel(level); }

public void setLevel(int l){ this.level = l; }

public int getLevel(){ return this.level; }

public void printInfo(){

System.out.println(\姓名：\工号：\+\工龄：\级别：\地址：\ System.out.println(\原工资：\

System.out.println(\涨工资后的工资：\Add().addPay(this.getLevel(), this.getPay())); }

private String getAddress() { return null; }

private String getName() { return null; } }

class Add{

public double addPay(int level,double pay){ if(level==0){

pay = (1+0.1)*pay; }

else if(level==1){ pay = (1+0.2)*pay; } else{

System.out.println(\级别只能为0或1，0表示普通员工，1则表示经理，操作无效！\ }

return pay; } }

public class ExtendsDemo {

public static void main(String[] args) { Manager m1 = new Manager(\张三\南京路\

Manager m2 = new Manager(\李四\长江路\ m1.printInfo();

System.out.println(\*************************\ m2.printInfo(); } }

编写一个测试类，产生一个员工和一个经理并输出其具有的信息。

1.定义一个接口Assaultable(可攻击的)，该接口有一个抽象方法attack()。

2.定义一个接口Mobile（可移动的）,该接口有一个抽象方法move()。

3.定义一个抽象类Weapon,实现Assaultable接口和Mobile接口，但并没有给出具体的实现方法。

4.定义3个类：Tank,Flighter,WarShip都继承自Weapon,分别用不同的方式实现Weapon类中的抽象方法。 5.写一个类Army,代表一支军队，这个类有一个属性是Weapon数组w（用来存储该军队所拥有的所有武器）；该类还提供一个构造方法，在构造方法里通过传一个int类型的参数来限定该类所能拥有的最大武器数量,并用这一大小来初始化数组w。该类还提供 一个方法addWeapon(Weapon wa),表示把参数wa所代表的武器加入到数组w中。在这个类中还定义两个方法attackAll()和moveAll()，让w数组中的所有武器攻击和移动。 6.写一个主方法去测试以上程序。

class Army { private Weapon[] w = null; private int size = 0; private Army() { } public Army(int i) { w = new Weapon[i]; } public void addWeapon(Weapon weapon) { if (size >= w.length) { System.out.println(\军队装备足够了!\

return; } else { w[size] = weapon; size++; } } public void attacAll() { for (Weapon wea : w) { if (wea != null) { wea.attack(); } } }

public void moveAll() { for (Weapon wea : w) { if (wea != null) { wea.move(); } } } }

package A1;

class Flighter extends Weapon { public void attack() { System.out.println(\attacks\

} public void move() { System.out.println(\

} }

public class NotSimple { public static void main(String[] args) { Army a = new Army(3); a.addWeapon(new Tank()); a.addWeapon(new Flighter()); a.addWeapon(new WarShip()); a.attacAll(); a.moveAll(); } } interface Assaultable { abstract public void attack(); } interface Mobile { abstract public void move(); } abstract class Weapon implements Assaultable, Mobile { }

class Tank extends Weapon { public void attack() { System.out.println(\attacks\

} public void move() { System.out.println(\ } }

package A1;

class WarShip extends Weapon { public void attack() { System.out.println(\ } public void move() { System.out.println(\ } }

class Army { private Weapon[] w = null; private int size = 0; private Army() { }

public Army(int i) { w = new Weapon[i]; }

public void addWeapon(Weapon weapon) { if (size >= w.length) {

System.out.println(\军队装备足够了!\

return; } else {

w[size] = weapon; size++; } }

public void attacAll() { for (Weapon wea : w) { if (wea != null) { wea.attack(); } } }

public void moveAll() { for (Weapon wea : w) { if (wea != null) { wea.move(); } } }

} package A1;

class Flighter extends Weapon {

public void attack() {

System.out.println(\ }

public void move() {

System.out.println(\ }} package A1;

public class NotSimple {

public static void main(String[] args) { Army a = new Army(3);

a.addWeapon(new Tank()); a.addWeapon(new Flighter()); a.addWeapon(new WarShip());

a.attacAll(); a.moveAll(); }

}

interface Assaultable {

abstract public void attack(); }

interface Mobile {

abstract public void move(); }

abstract class Weapon implements Assaultable, Mobile { } package A1;

class Tank extends Weapon { public void attack() {

System.out.println(\ }

public void move() {

System.out.println(\ } } package A1;

class WarShip extends Weapon { public void attack() {

System.out.println(\ }

public void move() {

System.out.println(\ } }

一个公司有2辆小汽车(car)，一辆公共汽车(bus)，其中：第一小辆汽车每天跑300公里；第二辆小汽车每天跑400公里；公共汽车每天跑500公里，已知小汽车每百公里耗油量为7升，公共汽车每百公里耗油量为10升，用接口编程计算每天所有交通工具的耗油量。

public interface Vehicle { int getfuel(); }

import c1.Vehicle;

public class bus implements Vehicle { int kil; bus(int k1){kil=k1;} public int getfuel(){ return(10*kil/100); } }

import c1.Vehicle;

class car implements Vehicle { int kil; car(int k1){kil=k1;} public int getfuel(){ return(7*kil/100); } }

import c1.bus; import c1.car;

import c1.company1; import c1.Vehicle;

public class company1 { Vehicle a[]; company1(){ a=new Vehicle[3]; a[0]=new car(300); a[1]=new bus(500); a[2]=new car(400); } int rf(){ int i=0; for(i=0;i

}

编写创建一个box类，在其中定义三个变量表示一个立方体的长、宽和高，定义一个构造方法对这三个变量进行初始化，然后定义一个方法求立方体的体积。创建一个对象，求给定尺寸的立方体的体积。

public class Box { double length; double wide; double high;

Box(double l,double w,double h){ this.length=l; this.wide=w; this.high=h; }

public void volume(){ double v;

v=length*wide*high;

System.out.println(\的体积是：\} }

public class Test {

public static void main(String[]args){ Box a=new Box(2,2,3); a.volume(); } }

定义一个学生类student，属性包括学号、班号、姓名、性别、年龄、班级总人数；方法包括获得学号、获得班号、获得姓名、获得性别、获得年龄、获得班级总人数、修改学号、修改班号、修改姓名、修改性别、修改年龄、以及一个tostring（）方法将student类中的所有属性组合成一个字符串。定义一个学生数组对象。设计程序进行测试。

public class Student { private String num; private String grade; private String name; private String sex; private int age; private int count ;

Student(String nu,String gr,String na,String se,int ag,int co){ this.num=nu; this.grade=gr; this.name=na; this.sex=se; this.age=ag; this.count=co; }

public String getNum() { return num; }

public void setNum(String num) { this.num = num; }

public String getGrade() { return grade; }

public void setGrade(String grade) { this.grade = grade; }

public String getName() { return name; }

public void setName(String name) { this.name = name; }

public String getSex() { return sex; }

public void setSex(String sex) { this.sex = sex; }

public int getAge() { return age; }

public void setAge(int age) { this.age = age; }

public int getcount() { return count; }

public void setcount(int count) { this.count = count; }

public String toString(){

return \学号\班号\姓名\性别\年龄\班级总人数\ } }

public class Test3 {

public static void main(String[]args){ Student s[]=new Student[2];

s[0]=new Student(\信管131\张晓晓\女\

s[1]=new Student(\信管131\小高密\女\

for(int i=0;i<2;i++){ System.out.println(s[i].toString()); }

} }

设计一个人员类person，其中包含一个方法pay，代表人员的工资支出。再以person类派生出教师类teacher和大学生类collegestudent其中： 教师：工资支出=基本工资+授课时数*30 大学生：奖学金支出

将人员类定义为抽象类，pay为抽象方法，设计程序实现多态性。

public abstract class Person {

public abstract void pay(int a,int b); public abstract void pay(); }

public class CollegeStudent { int award;

public void pay(int w){ this.award=w;

System.out.println(\的奖学金支出是：\ } }

public class Teacher extends Person{ int wage; int time; int p;

public void pay(int w,int t){ this.wage=w; this.time=t; p=wage+time*30;

System.out.println(\的工资支出是：\

}

@Override

public void pay() {

// TODO Auto-generated method stub } }

public class Test2 {

public static void main(String[]args){ Teacher a=new Teacher();

CollegeStudent b=new CollegeStudent(); a.pay(5000,50);

b.pay(3000); }

}

1． 将1～100之间的所有正整数在放在一个List

集合中，并将集合中索引位置是10的对象从集合中移除。

import java.util.*; public class Test {

public static void main(String[] args) {

List list1 = new ArrayList(); for (int i = 1; i <= 100; i++) {

list1.add(i); }

list1.remove(10); Iterator it = list1.iterator();

while (it.hasNext()) {

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

} } }

2.分别向Set集合以及List集合中添加“A”“、a”、“c”、”C”、”a”5个元素，观察重复值能否在List集合以及Set集中成功添加。

import java.util.ArrayList; import java.util.HashSet; import java.util.List; import java.util.Set; public class Test2 {

public static void main(String[] args) { Set set=new HashSet(); set.add(\ set.add(\ set.add(\ set.add(\ set.add(\

System.out.println(set); List list1=new ArrayList(); list1.add(\ list1.add(\ list1.add(\ list1.add(\ list1.add(\

System.out.println(list1) }

3. （List）已知有一个Worker 类如下：

public class Worker {

private int age; private String name; private double salary; public Worker (){}

public Worker (String name, int age, double salary){

this.name = name; this.age = age;

this.salary = salary; }

public int getAge() { return age; }

public void setAge(int age) { this.age = age; }

public String getName() { return name; }

public void setName(String name) { this.name = name; }

public double getSalary(){ return salary; }

public void setSalary(double salary){ this.salary = salary; }

public void work(){

System.out.println(name + “ work”); } }

完成下面的要求

1) 创建一个List，在List 中增加三个工人，基本信息如下： 姓名 年龄 工资 zhang3 18 3000 li4 25 3500 wang5 22 3200

2) 在li4 之前插入一个工人，信息为：姓名：zhao6，年龄：24，工资3300 3) 删除wang5 的信息

4) 利用for 循环遍历，打印List 中所有工人的信息

5) 利用迭代遍历，对List 中所有的工人调用work 方法。 package z3; public class Worker { private int age; private String name; private double salary;

public Worker (){ }

public Worker (String name, int age,

double salary){

this.name = name; this.age = age;

this.salary = salary; }

public int getAge() { return age; }

public void setAge(int age) { this.age = age; }

public String getName() { return name; }

public void setName(String name) { this.name = name; }

public double getSalary(){ return salary; }

public void setSalary(double salary){ this.salary = salary; }

public void work(){

System.out.println(name+\ } }

package z3;

import java.util.ArrayList; import java.util.Iterator; import java.util.List; public class Test3 {

public static void main(String[] args) { Worker w1=new Worker(\ Worker w2=new Worker(\ Worker w3=new Worker(\ Worker w4=new Worker(\ List list1=new ArrayList(); list1.add(w1); list1.add(w2); list1.add(w3); list1.add(1,w4);

list1.remove(w3);

for(int i=0;i

Worker wer=(Worker)list1.get(i);;

System.out.println(wer.getName()+\getAge()+\ }

Iterator it=list1.iterator(); while(it.hasNext()){

Worker w=(Worker) it.next(); w.work(); } }

}

（Map）利用Map，完成下面的功能：

从命令行读入一个字符串，表示一个年份，输出该年的世界杯冠军是哪支球队。如果该

年没有举办世界杯，则输出：没有举办世界杯。package z1;

import java.util.HashMap; import java.util.Scanner; public class Test1 {

public static void main(String[]args){ HashMap hm=new HashMap(); hm.put(\意大利\ hm.put(\巴西\ hm.put(\法国\ hm.put(\巴西\ hm.put(\德国\ hm.put(\阿根廷\ hm.put(\意大利\ hm.put(\阿根廷\ hm.put(\德国\ hm.put(\巴西\ hm.put(\英格兰\ hm.put(\巴西\ hm.put(\巴西\ hm.put(\德国\ hm.put(\乌拉圭\ hm.put(\意大利\ hm.put(\意大利\ hm.put(\乌拉圭\

System.out.println(\请输入一个年份：\ Scanner sc=new Scanner(System.in); String y=sc.nextLine(); System.out.print(y);

if(hm.containsKey(y)){

System.out.println(hm.get(y)); } else{

System.out.println(\没有举办世界杯\ } } }

完成下列要求：

1） 使用一个Map，以老师的名字作为键，以老师教授的课程名作为值，表示上述 课程安排。

2） 增加了一位新老师Allen 教JDBC 3） Lucy 改为教CoreJava

4） 遍历Map，输出所有的老师及老师教授的课程 5） *利用Map，输出所有教JSP 的老师。 package z2; import java.util.*; public class Test2{

public static void main(String[] args){ HashMap hm=new HashMap(); hm.put(\ hm.put(\ hm.put(\ hm.put(\ hm.put(\ hm.put(\ hm.put(\ hm.put(\

System.out.println(\添加后的结果是：

\

System.out.println(hm); hm.put(\

System.out.println(\替换后的结果是：

\

System.out.println(hm); Iterator it

=hm.entrySet().iterator(); while (it.hasNext()) {

System.out.println(it.next()); }

Set set=hm.keySet(); for(Object str:set){

if(hm.get(str).equals(\

System.out.println(\教

JSP的老师有：\

} } } }

（泛型）使用泛型，改写第5 题 import java.util.HashSet; import java.util.Iterator; import java.util.Scanner; import java.util.Set; public class Test3 {

public static void main(String[] args) { Set setWorker=new

HashSet();

Scanner sc=new Scanner(System.in); String str=sc.nextLine(); Iterator it

=setWorker.iterator(); while (it.hasNext()) { if (it.equals(str)) {

System.out.println(\放入HashSet

中时不会出现重复元素\ } } } }

Set）有如下两个类（只写了类的属性，请自行添加相

应的构造方法和get/set 方法）

要求，完善Worker 和Address 类，使得Worker 对象

能够正确放入HashSet 中：即将

Worker 放入HashSet 中时不会出现重复元素。并编写相应测试代码。 package z3;

public class Address {

private String addressName; private String zipCode;

public void address(String aN,String zC){ this.addressName=aN; this.zipCode=zC; }

public String getAddressName() { return addressName; }

public void setAddressName(String addressName) { this.addressName = addressName; }

public String getZipCode() { return zipCode; } public void setZipCode(String zipCode) { this.zipCode = zipCode; }

public class Worker{ private String name; private int age;

private double salary; private Address address;

public void worker(String n,int a,double

s,Address ad){ this.name=n; this.age=a; this.salary=s; this.address=ad; }

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; }

public double getSalary() { return salary; }

public void setSalary(double salary) { this.salary = salary; }

public Address getAddress() { return address; }

public void setAddress(Address address) { this.address = address; } } }

编写一个异常类MyException，再编写一个类Student，该类有一个产生异常的方法speak(int m)。 要求参数m的值大于1000时，方法抛出一个MyException对象。最后编写主类，在方法中创新Student对象，让该对象调用speak()方法。

public class MyException extends Exception{ public MyException(){ this(\发生异常了\ }

public MyException(String message) { super(message); } }

public class Student {

public void speak(int m)throws MyException{ if(m>1000){

throw new MyException(\发生了异常\ } } }

public class Test1 {

public static void main(String[] args) { Student s=new Student();

// MyException me=new MyException(); int m; try{

s.speak(1200);

}catch(MyException e){

System.out.println(\出现了异常\ } } }

q创建类Computer，该类中有一个计算两个数的最大公约数的方法。如果向该方法传递负整数，该方法就会抛出自定义异常。 package a2;

public class MyException extends Exception { private String reason;

public MyException(int x,int y){ reason=\出现异常\ }

public String getReason(){ return reason; } }

package a2; import java.util.Scanner;

public class Computer {

int m,n;

public void zdgys(int x,int y)throws MyException{

if(x<=0||y<=0)

throw new MyException(x,y); else{ if(x

int r=x%y; while(r!=0){ x=y; y=r; r=x%y; }

System.out.println(\最大公约数是：\

} }

public static void main(String[] args) {

int result =0;

Computer c=new Computer(); try{

System.out.println(\请输入两个数：\

Scanner s=new Scanner(System.in); int x=s.nextInt(); int y=s.nextInt();

c.zdgys(x, y);

}catch(MyException e){

System.out.println(e.getReason()); } } }

q自定义类Sanj，其中有成员 x,y,z,作为三边长，构造方法Sanj(a,b,c)分别给x,y,z赋值,方法求面积getArea和显示三角形信息(三个边长)showInfo，这2个方法中当三条边不能构成一个三角形时要抛出自定

义异常NotSanjiaoException，否则显示正确信息。在另外一个类中的主方法中构造一个Sanj对象(三边为命令行输入的三个整数)，显示三角形信息和面积，要求捕获异常。 package a3;

public class NotSanjiaoException extends Exception{ String reason;

public NotSanjiaoException(int a,int b,int c){ reason=\三条边不能构成三角形\}

public String getReason(){ return reason; } }

package a3;

public class Sanj { int x,y,z;

public Sanj(int a,int b,int c) {

this.x=a; this.y=b; this.z=c; }

public void getArea(){ int sum=x+y+z; double p=sum/2;

double s=Math.sqrt(p*(p-x)*(p-y)*(p-z)); System.out.println(\三角形的面积是：\ }

public void showInfo(){

System.out.println(\三角形的边长是：\ } }

package a3;

import java.util.Scanner; public class Test3 {

public static void main(String[] args) { int x,y,z ; System.out.println(\请输入三角形的边长\ Scanner sc=new Scanner(System.in); x=sc.nextInt(); y=sc.nextInt(); z=sc.nextInt(); try{

if(x+y<=z||x+z<=y||y+z<=x){

throw new NotSanjiaoException (x,y,z); } else{

Sanj sj1=new Sanj(x,y,z);

sj1.getArea(); sj1.showInfo(); }

}catch(NotSanjiaoException e){

System.out.println(e.getReason()); } } }

q写一个方法void sanjiao(int a,int b,int c)，判断三个参数是否能构成一个三角形，如果不能则抛出异常IllegalArgumentException，显示异常信息a,b,c+”不能构成三角形”，如果可以构成则显示三角形三个边长，在主方法中得到命令行输入的三个整数，调用此方法，并捕获异常。

public class IllegalArgumentException extends Exception{

String reason;

public IllegalArgumentException(int a,int b,int c){

reason=\异常信息a,b,c+”不能构成三角形\ }

public String getReason(){ return reason; } }

package a4;

import java.util.Scanner;

public class Triangle { //int a,b,c;

public static void sanjiao(int a,int b,int c)throws IllegalArgumentException{

// a=this.a; // b=this.b; // c=this.c;

if(a+b<=c||a+c<=b||b+c<=a){

throw new IllegalArgumentException(a, b,c);

} else{

System.out.println(a+\能构成三角形\ } }

public static void main(String[] args) {

System.out.println(\请输入三条边：\ Scanner sc=new Scanner(System.in); int a=sc.nextInt(); int b=sc.nextInt(); int c=sc.nextInt(); try {

sanjiao(a,b,c);

} catch (IllegalArgumentException e) { System.out.println(e.getReason()); }

} }

1. 程序功能：将键盘上输入的字符在屏幕上显示出来。

package z1;

import java.io.BufferedReader; import java.io.IOException;

import java.io.InputStreamReader; public class Test1 {

public static void main(String[] args) { BufferedReader in=new BufferedReader(new InputStreamReader(System.in));

System.out.println(\请输入一行数据：\ try { System.out.println(\您输入的是：\

} catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }

}

}

2. 程序功能：将保存在本地机当前文件夹中的

LX5_1.HTML 文本文件的内容在屏幕上显示出来，然后将其另存为LX5_1.txt 文件。

package z2;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException;

import java.io.OutputStreamWriter; public class Test2 { public static void main(String[] args) throws IOException {

FileReader in = new FileReader(\

BufferedReader br = new BufferedReader(in);

FileWriter out = new FileWriter(\

String str; while ((str = br.readLine()) != null) {

System.out.println(str); out.write(str + \ } in.close(); out.close(); } }

3. 编写一个java课的成绩统计程序，从键盘输入学生

姓名和成绩，程序按成绩排出名次，并统计出最高分、最低分、平均分。学生的个数在程序运行前是未知数。

package z3;

import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException;

import java.io.InputStreamReader; import java.nio.Buffer; import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class Test3{

public static void main(String[] args) {

Scanner sc=new Scanner(System.in);

System.out.println(\请输入学生数\

int s=sc.nextInt();

int[] a=new int[s]; System.out.println(\请输入学生成绩以逗号隔开\

BufferedReader br=new BufferedReader(new

InputStreamReader(System.in));

try { String str=br.readLine();

String[] s1=str.split(\

for(int i=0;i

a[i]=Integer.parseInt(s1[i]);

} } catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} int max=0; int min=100; int sum=0; for (int j = 0; j < a.length; j++) {

for (int i = j+1; i < a.length; i++) {

if(a[j]

System.out.print(a[j]); }

}

for(int j=0;j

if(a[j]>max){

max=a[j];

}

if(a[j]

min=a[j]; } sum+=a[j]; } System.out.println(\最高分数：\

System.out.println(\最低数\

System.out.println(\平均分数：\

} }

4.编写一个程序，类名为WordCount,统计单词“hello”在一篇英文文章（保存在文件

article.txt）中出现的次数，要求统计时忽略单词的大小写，统计结果在屏幕上打印出来的格式为：单词***在文章***中出现的次数为：10。提示：下面是String类中的几个方法：

public int indexOf(String str) //返回指定子字符串在此字符串中第一次出现处的索引。

public int indexOf(String str,int fromIndex) //从指定的索引开始,返回指定子字符串在此字符串中第一次出现处的索引。

public String

toUpperCase() // String 中的所有字符都转换为大写

public String toLowerCase

() // String 中的所有字符都转换为小写

package z4;

import java.io.BufferedReader; import java.io.FileReader; import java.io.IOException;

public class HelloCount { int getHelloCount(String aritleName,String hello) { int count=0; String sentense; try{

BufferedReader br=new BufferedReader(new

FileReader(aritleName));

hello=hello.toLowerCase();

while((sentense=br.readLine())!=null){

System.out.println(sentense);

sentense=sentense.toLowerCase(); int

index=sentense.indexOf(hello); while(index>=0){ count++;

index=sentense.indexOf(hello,index+hello.length()); } }

}catch (Exception e) {

System.out.println(\文件目录错1.误\ }

return count; }

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

String article=\ String hello=\

HelloCount h=new HelloCount();

System.out.println(\单词\在文章中出现的次数：

\ } } 4. 编写一个程序WriteLog.java实现如下功能：从键

盘输入若行文字（可能包含中文），当最后一行输入quit#时，退出程序且将输入内容除quit#外全部存入文件c:\\log.txt中

package z5;

import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.util.Scanner; public class WriteLog { private static PrintWriter out; public static void main(String[] args) { try { out = new PrintWriter(new OutputStreamWriter(new FileOutputStream(

\ } catch (FileNotFoundException e) { e.printStackTrace(); } Scanner in = new Scanner(System.in); String line =null; while (!\in.nextLine())) {

out.println(line); } out.flush(); out.close(); } }

编写程序:使用字符输入、输出流读取文件，将一段文字加密后存入文件，然后再读取，并将加密前与加密后的文件输出。

package IOTest;

import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.File;

import java.io.FileNotFoundException; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner;

public class Jiami {

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

BufferedReader br=new BufferedReader(new FileReader(new File(\

BufferedWriter bw=new BufferedWriter(new } FileWriter(new File(\ out.flush();

Scanner scan=new Scanner(System.in); out.close(); String str=scan.nextLine(); } char []c=str.toCharArray(); } System.out.println(); 3.编写程序：输入两个正整数m和n，求其最大公约数和最小 char []w=new char[c.length]; 公倍数。 for (int i = 0; i

} deff cd = new deff(); br.close(); m = cd.deff(a, b); } int n = a * b / m; } System.out.println(\最大公约数: \2. 编写程序:实现当用户输入姓名和密码时，将每一个姓名 System.out.println(\最小公倍数: \

和密码加在文件中，如果用户输入done，就结束程序。 }

package z5; } import java.io.FileNotFoundException; class deff { import java.io.FileOutputStream; public int deff(int x, int y) { import java.io.OutputStreamWriter; int t; import java.io.PrintWriter; if (x < y) { import java.util.Scanner; t = x; x = y; public class WriteLog { y = t; private static PrintWriter out; } while (y != 0) { public static void main(String[] args) { if (x == y) try { return x; out = new PrintWriter(new else { OutputStreamWriter(new FileOutputStream( int k = x % y;

\ x = y; } catch (FileNotFoundException e) { y = k; e.printStackTrace(); } } } System.out.println(\请输入用户名和密码， return x; 中间用逗号隔开。结束输入时输入‘done’\ }

Scanner in = new Scanner(System.in); } String line =null; while (!\5. 编写程序:输入一行字符，分别统计出其中英文字母、in.nextLine())) { 空格、数字和其它字符的个数。

out.println(line);

package z5;

import java.util.Scanner; public class T3 {

public static void main(String[] args) { System.out.println(\请输入一个字符串\ Scanner sc=new Scanner(System.in); String str =sc.nextLine(); char ch [] = new char[str.length()]; ch=str.toCharArray(); int eng=0 ,kong=0,shu=0,qi=0; for (int i = 0; i < ch.length; i++) { if (65ch[i] && ch[i]>122&& ch[i]!=32) { qi++; } } System.out.println(\英文字母有\ System.out.println(\空格有\ System.out.println(\数字有\ System.out.println(\其他字符有\}

}

一、数据库综合应用练习1： 1.在数据库中建立一个表，表名为student，其结构为：学号（num）、姓名（name）、性别（sex）、年龄（age）、成绩（score）

2.在student表中输入四条记录（自己设计具体数据内容）

3.在屏幕上显示表中的所有内容 4.增加两条学生记录： 05，李芳，女，20,76 06，张良，男，19,70 5.将每人的年龄增加2岁 6.删除成绩不及格的学生记录 7.显示最终表格的内容 package a1;

import java.io.InputStream; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Properties; public class JDBCUtils {

private static String url =

\tudent\

private static String driver =

\ private static String user = \

private static String password =\ static{ try{

Class.forName(driver);

}catch(ClassNotFoundException e){

System.out.println(\找不到驱动程序类 ，加载驱动失败！\

e.printStackTrace() ; } }

public static Connection getConnection() throws SQLException{

return DriverManager.getConnection(url, user, password); }

public static void release(Connection conn,Statement st,ResultSet rs){ if(rs!=null){ try{

rs.close();

}catch (Exception e) { e.printStackTrace(); }finally{

if(st!=null){ try{

st.close();

}catch (Exception e) { e.printStackTrace(); }finally{

if(conn!=null){ try{

conn.close(); }catch (Exception e) {

e.printStackTrace();

}finally{ }

} } } }

}

}

}

package a1;

import java.sql.*;

public class JdbcXianshi {

public static void main(String[] args) { Connection conn = null; PreparedStatement st = null; ResultSet rs = null; try { conn =JDBCUtils.getConnection(); String str=\order by num\

st = conn.prepareStatement(str); rs = st.executeQuery(); while (rs.next()) { System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.println(rs.getString(\

} } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { JDBCUtils.release(conn, st, rs); } } }

package a1;

import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException;

public class Add {

public static void main(String[] args) { Connection conn = null; PreparedStatement st = null; ResultSet rs = null; try { conn=JDBCUtils.getConnection(); String str=\values(?,?,?,?,?)\

st=conn.prepareStatement(str); st.setString(1, \ st.setString(2, \李芳\ st.setString(3, \女\ st.setInt(4, 20); st.setInt(5, 76); st.execute(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ JDBCUtils.release(conn, st, rs); } } }

package a1;

import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException;

public class AddAge { public static void main(String[] args) { Connection con=null; PreparedStatement st=null; ResultSet rs=null; try { con=JDBCUtils.getConnection(); String str=\age=age+2\

st=con.prepareStatement(str); st.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block

e.printStackTrace();

}finally{

JDBCUtils.release(con, st, rs); }

}

}

package a1;

import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; public class Delete {

public static void main(String[] args) { Connection con=null;

PreparedStatement st=null; ResultSet rs=null; try {

con=JDBCUtils.getConnection();

String str=\from student where score<60 \

st=con.prepareStatement(str); st.executeUpdate(); } catch (SQLException e) {

// TODO Auto-generated catch block e.printStackTrace(); }finally{

JDBCUtils.release(con, st, rs); } } }

package a1;

import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; public class XianShi2 {

public static void main(String[] args) { Connection conn = null;

PreparedStatement st = null; ResultSet rs = null; try {

conn=JDBCUtils.getConnection(); String str=\ st=conn.prepareStatement(str); rs=st.executeQuery(); while(rs.next()){

System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.print(rs.getString(\

System.out.println(rs.getString(\ }

} catch (SQLException e) {

// TODO Auto-generated catch block e.printStackTrace(); }finally{

JDBCUtils.release(conn, st, rs); } }

二、数据库综合应用练习2： 用java新建一个表格，表名为table，结构为：id int，name char，age int，score int

并为table表格增加三条记录，（具体数据自己设计）显示table表格中的所有信息

提示：增加表 Sql=“create table student(id int,name char,age int,score float)”;

删除表 sql=“drop table student”;

package sdjtu.hyJDBCTest; public class StudentBean { private String num; private String name; private String sex; private int age; private float score; public String getNum() { return num; }

public void setNum(String num) { this.num = num; }

public String getName() { return name; }

public void setName(String name) { this.name = name; }

public String getSex() { return sex; }

public void setSex(String sex) { this.sex = sex; }

public int getAge() { return age; }

public void setAge(int age) { this.age = age; }

public float getScore() { return score; }

public void setScore(float score) { this.score = score; } }

package sdjtu.hyJDBCTest; import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import sdjtu.hyJDBC.JDBCUtils; public class JdbcAdd {

public void add(StudentBean te) {

// TODO Auto-generated method stub Connection conn = null;

PreparedStatement st = null; ResultSet rs = null; try {

conn = JDBCUtils.getConnection(); String sql = \ + \ st = conn.prepareStatement(sql); st.setString(1, te.getNum()); st.setString(2, te.getName()); st.setString(3, te.getSex()); st.setInt(4, te.getAge()); st.setFloat(5, te.getScore()); st.execute();

} catch (Exception e) { e.printStackTrace(); } finally {

JDBCUtils.release(conn, st, rs); } }

public static void main(String[] args) { JdbcAdd jd=new JdbcAdd();

StudentBean te = new StudentBean(); te.setNum(\ te.setName(\李芳\ te.setSex(\女\ te.setAge(19); te.setScore(70); jd.add(te); } }

package sdjtu.hyJDBCTest; import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; public class JdbcDelete {

public static void main(String[] args) { Connection conn = null;

PreparedStatement st = null; ResultSet rs = null; try {

conn =

sdjtu.hyJDBC.JDBCUtils.getConnection();

String sql = \score<60\

st = conn.prepareStatement(sql); st.executeUpdate(); } catch (Exception e) { e.printStackTrace(); } finally {

sdjtu.hyJDBC.JDBCUtils.release(conn, st, rs); }

JdbcXianshi jd=new JdbcXianshi(); jd.qureyAll(); } }

package sdjtu.hyJDBCTest; import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; public class JdbcUpdate {

public static void main(String[] args) { Connection conn = null;

PreparedStatement st = null; ResultSet rs = null; try {

conn =

sdjtu.hyJDBC.JDBCUtils.getConnection(); String sql = \age=age+2\

st = conn.prepareStatement(sql); st.executeUpdate(); } catch (Exception e) {

e.printStackTrace(); } finally {

sdjtu.hyJDBC.JDBCUtils.release(conn, st, rs); } } }

package sdjtu.hyJDBCTest; import java.sql.Connection;

import java.sql.PreparedStatement; import java.sql.ResultSet; import sdjtu.hyJDBC.JDBCUtils; public class JdbcXianshi { public void qureyAll(){ Connection conn = null;

PreparedStatement st = null; ResultSet rs = null; try {

conn =

sdjtu.hyJDBC.JDBCUtils.getConnection();

String sql = \order by num\

st = conn.prepareStatement(sql); rs = st.executeQuery(); while (rs.next()) {

System.out.print(\学号\

System.out.print(\姓名\

System.out.print(\性别\

System.out.print(\年龄\

System.out.print(\成绩\

System.out.println(); }

} catch (Exception e) { e.printStackTrace(); } finally {

JDBCUtils.release(conn, st, rs); } }

public static void main(String[] args) { JdbcXianshi jd= new JdbcXianshi(); jd.qureyAll(); } }

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