習(xí)題課1.publicclassTest4_1 {publicstaticvoidmain(Stringargs[]) {intn=0;out:for(inti=1;i<6;i++)//設(shè)置標(biāo)號 {for(intj=1;j<3;j++) {if(i==3)breakout;//i=3時跳出循環(huán) n++; }

}System.out.println("循環(huán)已經(jīng)結(jié)束！n="+n);}}22.publicclassTest4_2{ publicstaticvoidmain(String[]args){ inti,j,k; for(i=0;i<4;i++){ for(k=0;k<i;k++){

System.out.print(""); } for(j=0;j<=6-2*i;j++) System.out.print("*"); System.out.println(); } }}33.classTest4_3{ intx=12,y=5,sum=0; publicvoidsum(){ intx=3; ints; s=x+y; sum=this.x+y; System.out.println("s="+s); System.out.println("sum="+sum); } publicstaticvoidmain(Stringargs[]){ Test4_3dt=newTest4_3(); dt.sum(); } }44.classBox{doublewidth,height,depth; Box(){this(5,5,5);}Box(doublex,doubley,doublez){width=x;height=y;depth=z;}doublevolume(){returnwidth*height*depth;}}publicclassTest4_4{publicstaticvoidmain(Stringargs[]) {Boxbox=newBox();Boxbox1=newBox(3,4,5);System.out.println("長方體體積為："+box.volume()+"和"+box1.volume());}}55.

classTest4_5{ publicstaticvoidmain(String[]args){ inta=30,b=2; try{ b-=2; System.out.println(a/b); } catch(Exceptione){ System.out.println("除數(shù)為0錯誤"); }System.out.println("a="+a+"\nb="+b); }}

66.

classExp{ inta1=5; staticinta2; staticvoidf1(){a2=16; } voidf2(inta){ a1=a; a2=30; }}7publicclassTest4_6extendsExp{ inta1=3; voidf2(inta){ a1=a;a2=5; }publicstaticvoidmain(Stringargs[]){ Expexp=newExp(); Test4_6exam=newTest4_6(); exp.f2(100); exam.f2(30); Exp.f1(); System.out.println(exp.a2+"\t"+exam.a2); System.out.println(exp.a1+"\t"+exam.a1); System.out.println();}}8classAnimal{privateStringname;privateintlegs;publicAnimal(){ this("AAA",4);}publicAnimal(Stringname,intlegs){ =name;this.legs=legs;}publicvoidsetName(Stringname){=name;}publicStringgetName(){returnname;}9publicvoidsetLegs(intlegs){ this.legs=legs;}publicintgetlegs(){ returnlegs;}publicvoidmove(){ System.out.println(+"Moving!!");}publicvoidmove(intn){for(inti=0;i<n;i++){System.out.println(+"Moving!!");}}}10classFishextendsAnimal{publicFish(Stringname){ super(name,0);}publicvoidmove(){ System.out.println(this.getName()+"Swimming!!");}}classBirdextendsAnimal{publicBird(Stringname){ super(name,2);}publicvoidmove(){ System.out.println(this.getName()+"Flying!!");}}11publicclassZoo{publicstaticvoidmain(Stringargs[]){Animala1=newAnimal();Animala2=newAnimal("動物",4);Fishf1=newFish("魚");Birdb1=newBird("鳥");a1.move();a2.move(4);f1.move();b1.move();f1.move(4);b1.move(4);}}121.設(shè)計類Date來顯示日期。具體要求如下：(12分)定義私有成員year、month和day，分別用于表示年、月、日，它們都是int型的數(shù)據(jù)。完成默認(rèn)構(gòu)造函數(shù)的定義，使Date對象的默認(rèn)值為：year=1、month=1和day=1。完成重載構(gòu)造函數(shù)Date(inty，intm，intd)的定義。完成成員函數(shù)print()的定義，使其以“年-月-日”的格式將Date對象的值輸出到屏幕上。例如：1949-10-1。在main()函數(shù)中，定義兩個Date的對象，一個調(diào)用默認(rèn)構(gòu)造函數(shù)，一個調(diào)用重載構(gòu)造函數(shù)。13publicclassDate{privateintyear;privateintmonth;privateintday;publicDate(intyear,intmonth,intday){ this.year=year;this.month=month;this.day=day;}publicDate(){ this(1,1,1);}publicvoidPrintInfo(){System.out.println("當(dāng)前日期為"+this.year+“-"+this.month+“-"+this.day);}publicstaticvoidmain(Stringargs[]){Dated1=newDate();Dated2=newDate(2012,12,13);d1.PrintInfo();d2.PrintInfo();

}}142.設(shè)計類Student類，具體要求如下：(12分)定義私有成員：學(xué)生學(xué)號num、學(xué)生成績score；定義構(gòu)造函數(shù)初始化對象；公有成員函數(shù)setnum(intn)用于設(shè)置學(xué)號、setscore(doubles)用于設(shè)置分?jǐn)?shù)、print()函數(shù)用于顯示學(xué)生學(xué)號和相應(yīng)的成績；在main函數(shù)中，建立2個Student類對象，設(shè)置學(xué)號以及分?jǐn)?shù)，最后顯示。15publicclassStudent{privateintnum;privatedoublescore;publicStudent(){ this(1001,0);}publicStudent(intnum,doublescore){ this.num=num;this.score=score;}publicvoidsetNum(intnum){ this.num=num;}publicvoidsetScore(doublescore){ this.score=score;}publicvoidPrintInfo(){ System.out.println("當(dāng)前學(xué)生信息：學(xué)號"+this.num+"成績："+this.score);}publicstaticvoidmain(Stringargs[]){Studentstu1=newStudent(1001,80);Studentstu2=newStudent(1002,85);stu1.setNum(1005);stu1.setScore(90);stu1.PrintInfo();}}173.設(shè)計類Circle類，具體要求如下：(12分)定義私有成員：類型為int，半徑r；靜態(tài)變量pi：類型為float，初值為3.14f定義構(gòu)造函數(shù)初始化對象；設(shè)置成員方法setR(intn)用于設(shè)置半徑，getR()用于返回半徑、getArea()用于求解面積和返回面積的值，print()函數(shù)用于顯示半徑和對應(yīng)的面積；在main函數(shù)中，建立2個Circle類對象，設(shè)置半徑并顯示結(jié)果。修改pi的值為3，分別輸出各對象面積值。18classCircle{privateintr;publicstaticfloatpi=3.14f;publicCircle(inta){r=a;}publicdoubleCArea(){returnpi*r*r;}publicvoidsetR(inta){r=a;}publicintgetR(){returnr;}}publicclassCircleTest{

publicstaticvoidmain(Stringargs[]){Circlec1=newCircle(5);Circlec2=newCircle(10);System.out.println("半徑為"+c1.getR()+"面積為"+c1.CArea());System.out.println("半徑為"+c2.getR()+"面積為"+c2.CArea());c1.pi=3;System.out.println("半徑為"+c1.getR()+"面積為"+c1.CArea());System.out.println("半徑為"+c2.getR()+"面積為"+c2.CArea());

}}publicclassTest{ publicstaticvoidmain(String[]args){ inta=3; intb=4; doublec=3/4; intd=3/4; System.out.println(c); System.out.println(d); System.out.println(++c); System.out.println(++d); }}19publicclassTest{ publicstaticvoidmain(String[]args){

inta='a'+3/8*6-12/5;

System.out.println(a); doubled=1.2e2/12+5.2*5-10/4; System.out.println(d); intb=5,c=3; a=b+++--c; System.out.println(a); }}20publicclassTest{publicstaticvoidmain(String[]args){inta=7,b=5;if(a!=b)if(a==b){a+=8;System.out.println(a);}else{b-=2;System.out.println(b);

}System.out.println(a);System.out.println(b);System.out.println(a+b);}}21classTime{privateinthour;privateintminute;privateintsecond;publicTime(inthour,intminute,intsecond){

this.hour=hour;this.minute=minute;this.second=second;}publicTime(){this(1,1,1);}publicvoidPrintInfo(){System.out.println(this.hour+":"+this.minute+":"+this.second);}}publicclassTest{publicstaticvoidmain(Stringargs[]){ Timed1=newTime(); Timed2=newTime(15,12,13);

d1.PrintInfo();d2.PrintInfo();}}22classVehicle{publicvoidstartUp(){System.out.println("一般交通工具的啟動方法");}publicvoidstop(){System.out.println("車輛?？?);

}

}classCarextendsVehicle{publicvoidstartUp(){System.out.println("轎車的啟動方法");

}}publicclassDemo1{publicstaticvoidmain(Stringargs[]){Vehiclev=newVehicle();Carc=newCar();System.out.println("實(shí)際調(diào)用的方法為：");v.startUp();c.startUp();c.stop();

}}23classPerson{Stringname;intage;publicvoidtell(){//輸出信息System.out.print("姓名:"+name);System.out.println();System.out.print("年齡:"+age);

}publicPerson(Stringn,inta){//輸入信息name=n;age=a;

}}publicclassDemo1{publicstaticvoidmain(Stringargs[]){Personper=newPerson("zhangsan",20);per.tell();

}}24publicclassDemo1{publicstaticvoidmain(String[]args){inta[][]={{1,2,3,4},{2,3,4,5},{3,4,5,6}};intb[][]=newint[4][3];inti,j;for(i=0;i<3;i++)for(j=0;j<4;j++)b[j][i]=a[i][j];for(i=0;i<4;i++){for(j=0;j<3;j++)System.out.print(b[i][j]+"");System.out.println();

}

}

}25classX1{intx=5;}publicclassDemo1extendsX1{intx=778;publicstaticvoidmain(Stringargs[])

{intm,n;Demo1s=newDemo1();X1ss=newX1();m=s.x;n=ss.x;System.out.println("m="+m);System.out.println("n="+n);

}}26271.設(shè)計簡單計算機(jī)程序。具體要求如下：1)繼承JFrame類設(shè)計界面，大小為300*100。。2)設(shè)置一個JButton對象，三個JTextField對象〔其中寬度為15列〕和一個JLabel對象。界面如以下圖所示。3)為“=”按鈕添加事件監(jiān)聽，實(shí)現(xiàn)當(dāng)點(diǎn)擊“=”按鈕后，在最右邊的JTextField中顯示運(yùn)行結(jié)果4)設(shè)計主程序，實(shí)現(xiàn)功能驗(yàn)證。2.importjavax.swing.*;importjava.awt.*;importjava.awt.event.*;//-----1分publicclassCDemoextendsJFrameimplementsActionListener{//-----2分JTextFieldtext1=newJTextField(5);JLabelJLb=newJLabel("+");JTextFieldtext2=newJTextField(5);JButtonjb=newJButton("=");JTextFieldtext3=newJTextField(10);publicCDemo(){//-----1分super("計算器");//-----1分setSize(300,100);setLayout(newFlowLayout());add(text1);add(JLb);add(text2);add(jb);add(text3);jb.addActionListener(this);//-----1分this.setVisible(true);}28 publicvoidactionPerformed(ActionEvente){//-----4分 if(e.getSource()==jb){if(text1.getText().equals("")||text2.getText().equals("")){ text3.setText("");} else{ inta=Integer.parseInt(text1.getText()); intb=Integer.parseInt(text2.getText()); text3.setText(String.valueOf(a+b)); } } }publicstaticvoidmain(Stringargs[]){//-----1分 newCDemo();}}291.

編寫一個JavaApplication程序，對｛10,20,18,11,8,23,32,12,34,22｝這10個整數(shù)排序并輸出。301.publicclassSorting{publicstaticvoidmain(Stringargs[])//------1分{inti,n=10,temp;//------1分inta[]={10,20,18,11,8,23,32,12,34,22};//------1分for(i=1;i<n;i++){//------1分for(intj=0;j<n-i;j++){//------1分if(a[j]>a[j+1]){//------3分temp=a[j];a[j]=a[j+1];a[j+1]=temp;

}

}

}for(i=0;i<n;i++)System.out.print(a[i]+"\t");//------1分

}

}31publicclassForDemo{publicstaticvoidmain(Stringargs[]){inta=3,b=4;if(a!=b)if(a==b){a+=8;System.out.println(a);}else{b-=2;System.out.println(b);

}System.out.println(a);System.out.println(b);System.out.println(a+b);}}32classPerson{

privateStringname;intage;publicPerson(){name="無名氏";age=20;}//無參構(gòu)造函publicPerson(Stringn,inta){//輸入信息name=n;age=a;}

publicvoidspeak(Stringword){

System.out.println(name+"說:"+word);}

publicvoidspeak(){

System.out.println(name+"無語");}}publicclassTest{

publicstaticvoidmain(Stringargs[]){Personper=newPerson("Rose",20);Personper2=newPerson();per.speak("我很好");per2.speak();}

}3334classVarargs{ publicintsum(inta,intb){returna+b;} publicintsum(inta,intb,intc){returna+b+c;} publicintsum(inta,intb,intc,intd){returna+b+c+d;}}publicclassTest{ publicstaticvoidmain(Stringargs[]){ Varargsvr=newVarargs(); System.out.println(vr.sum(1,2)); System.out.println(vr.sum(1,2,3)); System.out.println(vr.sum(1,2,3,4)); }}35publicclassTest{

publicstaticvoidmain(String[]args){

inti,j,k,n=0;

for(i=0;i<4;i++){

for(k=0;k<i;k++){

System.out.print(+