Compilation fails due to an error in line 23.
Compilation fails due to an error in line 29.
A ClassCastException occurs in line 29.
A ClassCastException occurs in line 31.
The value of all four objects prints in natural order.
第1题:
public static void main(String[]args){Integer i=new Integer(1)+new Integer(2);switch(i){case3:System.out.println("three");break;default:System.out.println("other");break;}}Whatistheresult?()
A.three
B.other
C.Anexceptionisthrownatruntime.
D.Compilationfailsbecauseofanerroronline12.
E.Compilationfailsbecauseofanerroronline13.
F.Compilationfailsbecauseofanerroronline15.
第2题:
以下程序的运行结果为?
class ValHold{
public int i = 10;
}
public class ObParm{
public static void main(String argv[]){
ObParm o = new ObParm();
o.amethod();
}
public void amethod(){
int i = 99;
ValHold v = new ValHold();
v.i=30;
another(v,i);
System.out.print( v.i );
}
public void another(ValHold v, int i){
i=0;
v.i = 20;
ValHold vh = new ValHold();
v = vh;
System.out.print(v.i);
System.out.print(i);
}
}
A.10030
B. 20030
C. 209930
D. 10020
第3题:
本题中,用表格表现某个月的月历,其中标题是从Sunday到Saturday,表格中的各项是可以修改的。 import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.table.*; public class java2 ( public static void main(String[]args) { try{ UIManager.setLookAndFeel(UIManager.getSys- temLookAndFeelClassName): } catch(Exception e) JFrame. frame=new CalendarTableFrame; frame.setDefaultCloseOperation(JFrame.EXIT_ oN CLOSE); frame.show; } } clasgCalendarTableFrame. extends JFrame { private static final int WIDTH=500; private static final int HEIGHT=150: private cells= { {null,null,null,new Integer(1),new Integer (2),new Integer(3),new Integer(4)), {new Integer(5),new Integer(6),new Integer (7).new Integer(8),new Integer(9),new Integer (10),new Integer(11)), {new Integer(12),new Integer(13),new Integer (14),new Integer(15),new Integer(16),new Integer (17),new Integer(18)), {new Integer(19),new Integer(20),new Integer (21),new Integer(22),new Integer(23),new Integer (24),new Integer(25)), {new Integer(26),new Integer(27),new Integer (28),new Integer(29),new Integer(30),new Integer (31),null} }; private String[]columnNames={ "Sunday","Monday","Tuesday","Wednesday", "Thursday","Friday","Saturday" }; public CalendarTableFrame{ setTitle("java2"); setSize(WIDTH,HEIGHT); JTable table=new ; getContentPane.add(new JScrollPane(table), BorderLayout.CENTER); } }
第4题:
Given: Integer i = new Integer (42); Long l = new Long (42); Double d = new Double (42.0); Which two expression evaluate to true?()
第5题:
class Beta { public static void main(String [] args) { Integer x = new Integer(6) * 7; if (x != 42) { System.out.print("42 "); } else if (x 〈 new Integer(44-1)) { System.out.println("less"); } else { System.out.print("done"); } } } 结果是什么?()
第6题:
23.Object[]myObjects={24.newinteger(12),25.newString(”foo”),26.newinteger(5),27.newBoolean(true)28.};29.Arrays.sort(myObjects);30.for(inti=0;i31.System.out.print(myObjects[i].toString());32.System.out.print(”);33.}Whatistheresult?()
A.Compilationfailsduetoanerrorinline23.
B.Compilationfailsduetoanerrorinline29.
C.AClassCastExceptionoccursinline29.
D.AClassCastExceptionoccursinline31.
E.Thevalueofallfourobjectsprintsinnaturalorder.
第7题:
public class Test { public static void add3 (Integer i) { int val = i.intValue(); val += 3; i = new Integer(val); } public static void main(String args[]) { Integer i = new Integer(0); add3(i); System.out.println(i.intValue()); } } What is the result? ()
第8题:
阅读以下说明和Java代码,将应填入(n)处的字句写在对应栏内【说明】
编写字符界面的Application程序,接收依次输入的10个整型数据,每个数据一行,将这些数据按升序排序后从系统的标准输出设备输出。
【Java代码】
import java.iO.*;
import java.util.* ;
public class compositor
{
public static void main ( String args[] )
{
final int NUMBER=10;
Vector dataVector=new Vector ();
try
{
BufferedReader br=new BufferedReader (
(1) InputStreamReader ( System.in ));
System.out.println ("请输入"+NUMBER+"个整数");
for (int i=0; i<NUMBER; i++ )
{
int temp=Integer.parselnt ( br.(2));
int low=0, high=i-1, mid=0;
while ((3))
{
System.out.println ( low+","+mid+","+high );
(4);
if ((( Integer ) dataVectOr.get( mid )) .intValue () ==temp )
{
data Vector.insertElementAt ( new Integer ( temp ), mid );
break;
}
else if ((( Integer ) dataVector.get ( mid )) .intValue ( ) >temp )
{
high=mid-1;
}
else
{
(5);
}
}
if ( low>high )
{
dataVector, insertElementAt ( new Integer ( temp ), iow );
}
}
//输出
System.out.println ( "\n升序的排序结果为; ");
for (int i=0; i<NUMBER; i++ )
{
System.out.print ( dataVector.get( i ) .toString () +"\t" );
}
}
catch ( NumberFormatException nfe)
{
System.out.println ( nfe.toString ());
System.out.println ( "整数格式输入错误。");
}
catch ( IOException ioe )
{
System.out.println ( ioe.toString ());
}
}
}
第9题:
public class Base { public static final String FOO = “foo”; public static void main(String[] args) { Base b = new Base(); Sub s = new Sub(); System.out.print(Base.FOO); System.out.print(Sub.FOO); System.out.print(b.FOO); System.out.print(s.FOO); System.out.print(((Base)s).FOO); } } class Sub extends Base {public static final String FOO=bar;} What is the result?()
第10题:
23. Object [] myObjects = { 24. new integer(12), 25. new String(”foo”), 26. new integer(5), 27. new Boolean(true) 28. }; 29. Arrays.sort(myObjects); 30. for( int i=0; i