5
10
12
17
24
第1题:
在下列源代码文件Test.java中, ( )是正确的类定义。
A.public class test{
B.public class Test{ public int x=0;public int x=0; public test (intx) public Test (int x){ {this.x=x; this.x=x;} }} }
C.public class Test extends T1,T2{
D.protected class Test extends T2{ public int=0;public int x=0; public Test(int x){Public Test (int x){ this.x=x;this.x=x: }} }}
第2题:
在下列源代码文件Test.java中,哪个选项是正确的类定义? ( )
A.public class test { public int x=0; public test(int x) { this.x=x; } }
B.public class Test { public int x=0; public Test(int x) { this.x=x; } }
C.public class Test extends Ti,T2 { public int x=0; public Test(int x) { this.x=x; } }
D.protected class Test extends T2 { public int x=0; public Test(int x) { this.x=x; } }
第3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
第4题:
1. public class Exception Test { 2. class TestException extends Exception {} 3. public void runTest() throws TestException {} 4. public void test() /* Point X */ { 5. runTest(); 6. } 7. } At Point X on line 4, which code is necessary to make the code compile?()
第5题:
1. public class Test { 2. public
第6题:
1. public class Test { 2. int x= 12; 3. public void method(int x) { 4. x+=x; 5. System.out.println(x); 6. } 7. } Given: 34. Test t = new Test(); 35. t.method(5); What is the output from line 5 of the Test class?()
第7题:
1. interface TestA { String toString(); } 2. public class Test { 3. public static void main(String[] args) { 4. System.out.println(new TestA() { 5. public String toString() { return “test”; } 6. } 7. } 8. } What is the result?()
第8题:
1. class Bar { } 1. class Test { 2. Bar doBar() { 3. Bar b = new Bar(); 4. return b; 5. } 6. public static void main (String args[]) { 7. Test t = new Test(); 8. Bar newBar = t.doBar(); 9. System.out.println(“newBar”); 10. newBar = new Bar(); 11. System.out.println(“finishing”); 12. } 13. } At what point is the Bar object, created on line 3, eligible for garbage collection?()
第9题:
Object x = t.findLarger(123, “456”);
int x = t.findLarger(123, new Double(456));
int x = t.findLarger(123, new Integer(456));
int x = (int) t.findLarger(new Double(123), new Double(456));
第10题:
5
10
12
17
24
第11题:
test
null
An exception is thrown at runtime.
Compilation fails because of an error in line 1.
Compilation fails because of an error in line 4.
Compilation fails because of an error in line 5.
第12题:
5
10
12
17
24
第13题:
在下列源代码文件Test.java中,哪个选项是正确的类定义?
A.public class test{ public int x=0; public test(int x ) { this.x=x; } }
B.public class Test { public int x=0; public Test(int x ) { this.x=x; } }
C.public class Test extends T1 T2 { public int x=0; public Test(int x){ this.x=x; } }
D.protected class Test extends T2 { public int x=0; public Test(int x) { this.x=x; } }
第14题:
A. 7
B. 6
C. 5
D. 8
第15题:
package test1; public class Test1 { static int x = 42; } package test2; public class Test2 extends test1.Test1 { public static void main(String[] args) { System.out.println(“x = “ + x); } } What is the result?()
第16题:
1.public class Test{ 2.int x=12; 3.public void method(intx){ 4.x+=x; 5.System.out.println(x); 6.} 7.} Given: 34.Test t=new Test(); 35.t.method(5); What is the output from line 5 of the Test class?()
第17题:
1. interface foo { 2. int k = 0; 3. } 4. 5. public class test implements Foo ( 6. public static void main(String args[]) ( 7. int i; 8. Test test = new test (); 9. i= test.k; 10.i= Test.k; 11.i= Foo.k; 12.) 13.) 14. What is the result?()
第18题:
Given the following code: public class Test { void printValue(int m){ do { System.out.println("The value is"+m); } while( --m > 10 ) } public static void main(String arg[]) { int i=10; Test t= new Test(); t.printValue(i); } } Which will be output?()
第19题:
Consider the following class: class Test(int i) { void test(int i) { System.out.println(“I am an int.”); } void test(String s) { System.out.println(“I am a string.”); } public static void main(String args) { Test t=new Test(); char ch=“y”; t.test(ch); } } Which of the statements below is true?()
第20题:
1. public class A { 2. public String doit(int x, int y) { 3. return “a”; 4. } 5. 6. public String doit(int... vals) { 7. return “b”; 8. } 9. } Given: 25. A a=new A(); 26. System.out.println(a.doit(4, 5)); What is the result?()
第21题:
No code is necessary.
throws Exception
catch ( Exception e )
throws RuntimeException
catch ( TestException e)
第22题:
x = 0
x = 42
Compilation fails because of an error in line 2 of class Test2.
Compilation fails because of an error in line 3 of class Test1.
Compilation fails because of an error in line 4 of class Test2.
第23题:
Line 5 will not compile, because void methods cannot be overridden.
Line 12 will not compile, because there is no version of test() that rakes a charargument.
The code will compile but will throw an exception at line 12.
The code will compile and produce the following output: I am an int.
The code will compile and produce the following output: I am a String.
第24题:
Compilation succeeds.
An error at line 2 causes compilation to fail.
An error at line 9 causes compilation to fail.
An error at line 10 causes compilation to fail.
An error at line 11 causes compilation to fail.