在Java中,下列代码将输出()。 1. public class integerequals 2. { 3. public static void main (String args[]) 4. { 5. Integer a= new Integer(3); 6. Integer b= new Integer(3); 7. System.out.println(a==b); 8. } 9. }
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:
class Super { public Integer getLenght() { return new Integer(4); } } public class Sub extends Super { public Long GetLenght() { return new Long(5); } public static void main(String[] args) { Super sooper = new Super(); Sub sub = new Sub(); System.out.println( sooper.getLenght().toString() + “,” + sub.getLenght().toString() ); } } What is the output?()
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:
1. public class Target { 2. private int i = 0; 3. public int addOne() { 4. return ++i; 5. } 6. } And: 1. public class Client { 2. public static void main(String[] args) { 3. System.out.println(new Target().addOne()); 4. } 5. } Which change can you make to Target without affecting Client?()
第5题:
1. public class Outer{ 2. public void someOuterMethod() { 3. // Line 3 4. } 5. public class Inner{} 6. public static void main( String[]argv ) { 7. Outer o = new Outer(); 8. // Line 8 9. } 10. } Which instantiates an instance of Inner?()
第6题:
编译和运行以下代码结果为:
1. public class EqualsTest{
2. public static void main(String args[]){
3. byte A=(byte)4096;
4. if(A== 4096、System.out.println("Equal");
5. else System.out.println("Not Equal");
6. }
7. }
A.在第3行出现转换丢失精度的编译错误.
B.输出 "Not Equal".
C.输出 "Equal".
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:
下列程序中,实现将封装数据类型Integer和基本数据类型int之间的转换,以及Integer,int类型和String类型之间的转换。请将程序补充完整。
程序运行结果如下:
123
456
456
public class ex7_1{
public static void main(String[]args) {
Integer intObj;
int n;
String s;
intObj = new Integer(123);
n=intObj.__________;
System.out.printin(Integer.toString(n));
s=new String("456");
intObj=Integer._________;
System.out.println(intObj.__________);
n=Integer.parseInt(s);
System.out.println(Integer.toString(n));
}
}
第9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10题:
1. public class A { 2. void A() { 3. System.out.println(“Class A”); 4. } 5. public static void main(String[] args) { 6. new A(); 7. } 8. } What is the result?()