更多"[单选题]已知有下列类的说明,则下列哪个语句是正确的?
public"的相关试题:
[单选题] 设有如下程序
Public class test {
Public static void main(String args[]) {
Integer intObj=Integer.valueOf(args[args.length-1]);
Int i = intObj.intValue();
If(args.length > 1)
System.out.println(i);
If(args.length > 0)
System.out.println(i - 1);
Else
System.out.println(i - 2);
}
}
运行程序 , 输入如下命令:
Java test 2
则输出为:
A. test
B. test -1
C. 0
D. 1
E. 2
[单选题]下列代码的执行结果是
public class Test
{ public int aMethod()
{ static int i=0; i++; System.out.println(i); }
public static void main(String args[])
{ Test test = new Test(); test.aMethod(); }
}
A.编译错误
B.0
C.1
D.运行成功,但不输出
[单选题]下列代码的执行结果是:
public class Test {
public static void main(String[] args) {
int[] x={0,1,2,3};
for(int i=0;i<3;i+=2){
try{
System.out.println(x[i+2]/x[i]+x[i+1]);
}catch(ArithmeticException e){
System.out.println("error1");
}catch(Exception e){
System.out.println("error2");
}
}
}
}
A.error1
B.error2
C.error1
error2
D.2
error2
[单选题]下列程序的输出结果是:
public class Test{
public static void main(String[] args){
int [] array={2,4,6,8,10};
int size=6;
int result=-1;
try{
for(int i=0;iA.Catch---1
B.Catch---2
C.Catch---3
D.以上都不对
[单选题] 下列程序运行的结果为:
Public class test {
Public static void main(String args[]) {
Int i;
Float f = 2.3f ;
Double d = 2.7;
I = ((int)Math.ceil(f)) * ((int)Math.round(d));
System.out.println(i);
}
}
A. 4
B. 5
C. 6
D. 6.1
E. 9
[单选题]阅读下列程序
public class Test implements Runnable{
private int x=0;
private int y=o;
boolean flag=true;
public static void main(string[ ] args) {
Test r =new Test( );
Thead t1=new Thead(r);
Thead t2=new Thead(r);
t1.start( );
t2.start( );
}
public void run(){
while(flag) {
x++;
y++;
System.out.println("(" +x_ ","+y+")");
if (x>=10)
flag=false;
}
}
}
下列对程序运行结果描述的选项中,正确的是:
A.每行的(x,y)中,可能有;每一对(x,y)值都出现两次。
B.每行的(x,y)中,可能有;每一对(x,y)值仅出现一次。
C.每行的(x,y)中,可能有x=y;每一对(x,y)值都出现两次。
D.每行的(x,y)中,可能有x=y;每一对(x,y)值都出现一次。
[单选题] 下列代码的执行结果是: ( )
Public class Test1{
Public static void main(String args[]){
Float t=9.0f;
Int q=5;
System.out.println((t++)*(--q));
}
}
A. 40
B.40.0
C.36
D.36.0
[单选题] 以下程序调试结果为:
Public class Test {
Int m=5;
Public void some(int x) {
M=x;
}
Public static void main(String args []) {
New Demo().some(7);
}
}
Class Demo extends Test {
Int m=8;
Public void some(int x) {
Super.some(x);
System.out.println(m);
}
}
A.5
B. 8
C. 7
D.无任何输出
E.编译错误
[多选题] 类 Test1 定义如下:
1 . public class Test1{
2 . public float aMethod ( float a , float b ) { }
3 .
4 . }
将以下哪种方法插入行 3 是不合法的。( )
A. public float aMethod ( float a , float b , float c ) { }
B. public float aMethod ( float c , float d ) { }
C.public int aMethod ( int a , int b ) { }
D.private float aMethod ( int a , int b , int c ) { }
[单选题]下列程序的运行结果是:
public class test{
private String[] data={"10","10.5"};
public void fun(){
double s=0;
for(int i=0;i<3;i++){
try{
s=s+Integer .parseInt(data[i]);
}catch(Exception e{
System.out.print("errorl:"+data[i]);
}
}
}
public static void main(String[]args){
try{
test d=new test();
d .fun();
}catch(Exception e){
System.out.println("error2");
}
}
}
A.errorl:10.5
B.error2
C.errorl:10.5 error2
D.以上都不对
[单选题] 在Java中,以下程序编译运行后的输出结果为( )。
Public class Test {
Int x, y;
Test(int x, int y) {
This.x = x;
This.y = y;
}
Public static void main(String[] args) {
Test pt1, pt2;
Pt1 = new Test(3, 3);
Pt2 = new Test(4, 4);
System.out.print(pt1.x + pt2.x);
}
}
A. 6
B. 3 4
C. 8
D. 7
[单选题]在程序的下划线处应填入的选项是:
public class Test_____{
public static void main(String args[]){
Test t = new Test();
Thread tt = new Thread(t);
tt.start();
}
public void run(){
for(int i=0;i<5;i++){
System.out.println("i="+i);
}
}
}
A.implements Runnable
B.extends Thread
C.implements Thread
D.extends Runnable
[单选题]下列代码编译或执行结果的描述中,正确的是:
class Test{
public static void main(String args[]){
TestThread pm1 = new TestThread("One");
pm1.start();
TestThread pm2 = new TestThread("Two");
pm2.start();
}
}
class TestThread extends Thread{
private String sTname="";
TestThread(String s){
sTname = s;
}
public void run(){
for(int i=0;i<2;i++){
try {
sleep(1000);
} catch (InterruptedException e) {}
System.out.println(sTname+" ");
}
}
}
A.不能通过编译,TestThread 类中不能定义变量和构造方法
B.输出One One Two Two
C.输出Two One One Two
D.选项B 或C 都有可能出现
[单选题]已知:
class Base {
public Base(String s) {
System.out.print(“B”);
}
}
public class Derived extends Base {
public Derived (String s) {
System.out.print(“D”);
}
public static void main(String [] args) {
new Derived (“C”);
}
}
那么结果为?
A.BD
B.DB
C.C
D.编译错误
[单选题]阅读下列程序
public class VariableUse{
public static void main (String[] args) {
int a;
if (a==8) {
int b=9;
System.out.println("a = "+a);
System.out.println("b = "+b);
}
System.out.println("a = "+a);
System.out.println("b = "+b);
}
}
该程序在编译时的结果是:
A.变量a未赋值
B.第二个System.out.println(“b = ”+b)语句中,变量b作用域有错
C.第二个System.out.println(“a = ”+a)语句中,变量a作用域有错
D.第一个System.out.println(“b = ”+b)语句中,变量b作用域有错
[单选题]已知:
class A {
public final void m() {
System.out.println(“A.m”);
}
}
public class B extends A {
public void m() {
System.out.println(“B.m”);
super.m();
}
public static void main(String [] args) {
new B().m();
}
}
那么结果为?
A.A.m
B.B.m
C.B.m
A.m
D.编译错误
[单选题]以下程序的调试结果为?
Public class Outer{
Public String name = "Outer";
Public static void main(String argv[]){
Inner i = new Inner();
I.showName();
}
Private class Inner{
String name =new String("Inner");
Void showName(){
System.out.println(name);
}
}
}
A.输出结果 Outer
B.输出结果 Inner
C.编译错误,因 Inner 类定义为私有访问
D.在创建 Inner 类实例的行出现编译错误
[单选题]下面代码的输出结果是:()
Public class Main {
Public static void main(String[] args) {
Int n1 = 1;
Int n2 = 2;
N1 = n1 + n2;
N2 = n1 - n2;
N1 = n1 - n2;
System.out.println(n1 + "," + n2);
}
}
A. 1,2
B. 2,1
C. 1,3
D. 3,2
[多选题]设有如下代码:
Class Base{}
Public class MyCast extends Base{
Static boolean b1=false;
Static int i = -1;
Static double d = 10.1;
Public static void main(String argv[]){
MyCast m = new MyCast();
Base b = new Base();
//Here
}
}
则在 //Here 处插入哪个代码将不出现编译和运行错误。
A. b=m;
B. m=b;
C. d =i;
D. b1 =i;