JAVA编程思想课后习题答案

Java编程思想（第四版）习题答案

第二章

练习1：publicclassPrimitiveTest{

}

练习2：publicclassHelioWorld{

}

练习3：publicclassATNTest{

}

练习4：publicclassDataOnlyTest{

classDataOnly{

inti;

doubled;

booleanb;

voidshow(){

System>out>println(i);

System>out^println(d);

publicstaticvoidmain(String[]args){

}classATypeName{

}inti;

doubled;

booleanb;

voidshow(){

}System>out>println(i);

System>out>println(d);

System>out、println(b);

publicstaticvoidmain(String[]args){

publicstaticvoidmain(String[]args){

}System>out、println("HelloWorld!");staticinti;

staticcharc;

}

publicstaticvoidmain(String[]args){

System>out、println("int="+i);

System>out>println("char="+c);

ATypeNamea=newATypeName();

a、i=3;

a、d=2、71828;

a、b=false;

a、show();

}}}}System>out、println(b);

DataOnlydata=newDataOnlyO;

data>i=3;

data、d=2^71828;

data、b=false;

data、show();

练习5：publicclassD0Test2{

}

练习6：publicclassStorageTest{

)

练习7：

classStaticTest{

}staticinti=47;

}classStoreStuff{

}intstorage(Strings){

}

}classDataOnly{

}inti;

doubled;

booleanb;

voidshow(){

}

publicstaticvoidmain(String[]args){

System>out、println(i);

System>out、println(d);

System>out、println(b);

DataOnlydata=newDataOnlyO;

data>i=234;

data、d=2、1234545;

data、b=true;

data、show();

publicstaticvoidmain(String[]args){

returns、length()*2;

StoreStuffx=newStoreStuff();

System>out、println(x>storage("hi"));

classIncrementable{

}

publicclassITest{

}

练习8：classStaticTest{

)

classIncrementable{

}

publicclassOneStaticTest{

publicstaticvoidmain(String[]args){

System>out、println("StaticTest、i="+StaticTest、i);迁终横f鸵镶噩套留。

StaticTeststl=newStaticTest();

StaticTestst2=newStaticTest();

System>out>println("stl>i="+stl>i);

System>out、println("st2^i="+st2>i);

lncrementable>increment();

System>out、println("Afterlncrementable>increment。called:")做谆页鸦

锚缠税。

System>out>println("stl>i="+stl>i);

System>out、println("st2^i="+st2>i);

lncrementable>increment();

System>out、println("Afterlncrementable>incrementcalled:");金句蹦I'M镰痛

黠稳。

System>out、println("stl^i="+stl>i);

Systemout、println("st2^i="+st2>i);

stl>i=3;

System>out、println("Afterstl>i=3,");

staticvoidincrement(){StaticTest>i++;}

staticinti=47;

publicstaticvoidmain(String[]args){

System>out、println("StaticTest>i="+StaticTest、i);痪楣责诙鹤赢镜。

StaticTeststl=newStaticTest();

StaticTestst2=newStaticTest();

System>out、println("stl>i="+stl>i);

System>out>println("st2>i="+st2、i);

Incrementablesf=newlncrementable();

sf、increment();

System>out、println("Aftersf^increment。called:");鹿梆鬟留屯负含焦秋。

System>out、println("stl^i="+stl>i);

Systemout、println("st2^i="+st2>i);

lncrementable>increment();

System>out、println("Afterlncrementable>incrementcalled:");篇宾缠阵颖

工赖。

System、out、println("stl>i="+stl>i);

System>out、println("st2>i="+st2>i);

}

staticvoidincrement(){StaticTest>i++;}

}}System>out、println("stl>i="+stl>i);

SystemAout、println("st2>i="+st2>i);

System>out、println("CreateanotherStaticTest,st3>");时娈谑萦展昂辉开。

StaticTestst3=newStaticTest();

System>out、println("st3>i="+st3>i);

练习9：publicclassAutoboxTest{

)

练习10：publicclassCommandArgTest{

publicstaticvoidmain(String[]args){

Jbooleanb=false;

charc='x';

bytet=8;

shorts=16;

inti=32;

longI=64;

floatf=0^32f;

doubled=0>64;

BooleanB=b;

System>out>println("booleanb="+b);

System>out>println("BooleanB="+B);

CharacterC=c;

System>out>println("charc="+c);

System>out、println("CharacterC="+C);

ByteT=t;

System>out>println("bytet="+t);

System>out>println("ByteT="+T);

ShortS=s;

System>out、println("shorts="+s);

System>out>println("ShortS="+S);

IntegerI=i;

System>out、println("inti="+i);

System>out>println("lntegerI="+I);

LongL=I;

System>out、println("longI="+I);

System>out>println("LongL="+L);

FloatF=f;

SystemAout>println("floatf="+f);

System>out、println("FloatF="+F);

DoubleD=d;

System>out>println("doubled="+d);

System、out、println("DoubleD="+D);

}publicstaticvoidmain(String[]args){

}System>out>println("args[O]="+args[0]);

System>out、println("args[l]="+args[l]);

System>out、println("args[2]="+args[2]);

练习11：

publicclassRainbow{

)

classAIITheColorsOfTheRainbow{

}

练习12：publicclassDocTest{

)

练习13-1：publicclassDocumentation1{

/**Afieldcomment*/

publicinti;

/**Amethodcomment*/

publicvoidf(){}

/**Entrypoingtoclass&application、

*@paramargsarrayofstringarguments

*@throwsexceptionsNoexceptionsthrown

*/

publicstaticvoidmain(String[]args){

}System>out、printlnC'Hello,it's:");

System>out^println(newDate());

intanlntegerRepresentingColors=0;

inthue=0;

voidchangeTheHueOfTheColor(intnewHue){

}

intchangeColor(intnewColor){

JreturnanlntegerRepresentingColors=newColor;

hue=newHue;

publicstaticvoidmain(String[]args){

}AIITheColorsOfTheRainbowate=newAIITheColorsOfTheRainbow();^IBiJ^fflt

翥勋金丸

System>out、println("atc^anlntegerRepresentingColors="+atc^

anlntegerRepresentingColors);^ate、changeColor(7);

ate、changeTheHueOfTheColor(77);

System>out、println("Aftercolorchange,atc>anlntegerRepresentingColors

="+atc、Systemout、println("atc^hue="+atc^hue);

抛脑睡刹铜噜。

anlntegerR即resentingColors);师鳗帽卖音菁鹦禊。)

2：publicclassDocumentation2{

}

3：publicclassDocumentations{

}

练习14：publicclassDocumentation4{

publicinti=2;

privateintj=3;

publicstaticvoidmain(String[]args){

Dated=newDate();

)

练习15：publicclassHelloDocTest{

publicstaticvoidmain(String[]args){

)

练习16：

classTree{

)

}intheight;

Tree(){

}

Tree(intinitialHeight){

}

voidinfo(){

)

voidinfo(Strings){

System>out、println(s+Treeis"+height+"feettall")才备节鼻巾矍谛钢攒。

System>out>println("Treeis"+height+"feettall");敛朝掰群区谆。

height=initialHeight;

System>out、println("Creatingnewtreethatis"+height+"feettall");馈搪食布

税褛透证。

System>out>println("Plantingaseedling");

height=0;

System>out>println("HelloWorld!");

}

}System>out、println("d="+d);

publicstaticvoidmain(String[]args){

}Dated=newDate();

System>out^println("d="+d);

Dated=newDate();

voidshowDate(){

System>out、println("Date="+d);

)

publicclassOverloading{

}publicstaticvoidmain(String[]args){

}for(inti=0;i<5;i++){

}

//Overloadedconstructor:

newTree();Treet=newTree(i);

t>info();

t、info("overloadingmethod");

第三章

练习1：publicclassPrintTest{

)

练习2：classTube{

}

publicclassAssign{

)

练习3：classBox{

)

publicclassPassObject2{

staticvoidf(Boxy){

}

publicstaticvoidmain(String[]args){y>a=2、71828f;

floata;

publicstaticvoidmain(String[]args){

}Tubetl=newTube();

Tubet2=newTube();

tl、level=0>9f;

t2、level=0、47f;

P>rintln("l:tl>level:"+tl>level+",t2>level:"+t2^level);摩獐诲^苏J庸

Mo

tl=t2;

P、rintln("2:tl>level:"+tl>level+",t2>level:"+t2>level);

tl>level=0、27f;

P、rintln("3:tl>level:"+tl、level+”,t2、level:"+t2、level);奖渊俨]贺^邺

雏。阖^觇发赢顶

publicstaticvoidmain(String[]args){

JprintC'Hello,fromshortform>");

P、rintln("Hellofromgreggordonform>");

System>out、println("Hellofromlongform>");

floatlevel;

}}Boxx=newBox();

x、a=3、1416f;

printf'l:x>a="+x>a);

f(x)；

print("2:x>a="+x、a);

练习4：classVelocitycalculator{

)

publicclassVelocityTester{

)

练习5：classDog{

}

publicclassDogTest{

publicstaticvoidmain(String[]args){

Dogspot=newDog();

spot、setName("Spot");

spot>setSays("Ruff!");

Stringname;

Stringsays;

voidsetName(Stringn){

)

voidsetSays(Strings){

}

voidshowName(){

}

voidspeak(){

}P>rintln(says);

P、rintln(name);

says=s;

name=n;

publicstaticvoidmain(String[]args){

}floatd=565>3f;

floatt=3>6f;

System>out、println("Distance:"+d);

System>out、println("Time:"+1);

、

floatv=Velocitycalculatorvelocity(dzt);

System>out^println("Velocity:"+v);

staticfloatvelocity(floatd,floatt){

}if(t==0)returnOf;

elsereturnd/t;

}}Dogscruffy=newDog();

scruffy>setName("Scruffy");

scruffy>setSays("Wurf!");

spot、showName();

spot>speak();

scruffy>showName();

scruffy>speak();

练习6：classDog{

)

publicclassDogCompare{

publicstaticvoidmain(String[]args){

Dogspot=newDog();

spot、setName("Spot");

spot>setSays("Ruff!");

D