public void m1() { }
protected void m1() { }
private void m1() { }
void m2() { }
public void m2() { }
protected void m2() { }
第1题:
若在类A中有一个无形式参数且无返回值的方法m1(),而且在调用这个方法时可以使用类名称而不是对象名称,那么声明这个方法的形式为( )。
A.static void m1 ()
B.public void m1 ()
C.final void m1 ()
D.abstract void m1;
第2题:
public class ExceptionTest { class TestException extends Exception {} public void runTest () throws TestException {} public void test () /* Point X*/ { runTest (); } } At point X on line 4, which code can be added to make the code compile?()
第3题:
A.int foo() { /* more code here */ }
B.void foo() { /* more code here */ }
C.public void foo() { /* more code here */ }
D.private void foo() { /* more code here */ }
E.protected void foo() { /* more code here */ }
第4题:
Given the following code, write a line of code that, when inserted at the indicated location, will make the overriding method in Extension invoke the overridden method in class Base on the current object. class Base { public void print( ) { System.out.println("base"); } } class Extention extends Base { public void print( ) { System.out.println("extension"); // insert line of implementation here } } public class Q294d { public static void main(String args[]) { Extention ext = new Extention( ); ext.print( ); } } Fill in a single line of implementation.()
第5题:
1. class Alpha { void m1() {} } 2. class Beta extends Alpha { void m2() { } } 3. class Gamma extends Beta { } 4. 5. class GreekTest { 6. public static void main(String [] args) { 7. a Alpha [] a = {new Alpha(), new Beta(), new Gamma() }; 8. for(Alpha a2 : a) { 9. a2.m1(); 10. if (a2 instanceof Beta || a2 instanceof Gamma) 11. //insert code here 12. } 13. } 14. } 哪一行代码插入到第11行,将编译但是会在运行时产生异常?()
第6题:
class One { void foo() {} } class Two extends One { //insert method here } Which three methods, inserted individually at line 14, will correctly complete class Two?()
第7题:
Which two code fragments will execute the method doStuff() in a separate thread?()
第8题:
A.public void m1() { }
B.protected void m1() { }
C.private void m1() { }
D.void m2() { }
E.public void m2() { }
F.protected void m2() { }
G.private void m2() { }
第9题:
interface A { public int getValue() } class B implements A { public int getValue() { return 1; } } class C extends B { // insert code here } Which three code fragments, inserted individually at line 15, make use of polymorphism?()
第10题:
Which three will compile and run without exception?()