a++;
b++;
c++;
d++;
e++;
第1题:
以下程序的输出结果为:
public class test {
public static void main(String args[]) {
int s=0;
for (int k=0;k<=10;k++)
s+=method(2,k)-1;
System.out.println(s);
}
public static int method(int n,int m) {
if (m==0)
return 1;
else
return n*method(n,m-1、;
}
}
A. 2048
B. 1024
C. 2036
D.2000
第2题:
public class test ( public static void main (String args) { int i = 0xFFFFFFF1; int j = ~i; } ) What is the decimal value of j at line 5?()
第3题:
Which statements can be inserted at the indicated position in the following code to make the program write 1 on the standard output when run?() public class Q4a39 { int a = 1; int b = 1; int c = 1; class Inner { int a = 2; int get() { int c = 3; // insert statement here return c; } } Q4a39() { Inner i = new Inner(); System.out.println(i.get()); } public static void main(String args[]) { new Q4a39(); } }
第4题:
Which line contains a constructor in this class definition?() public class Counter { // (1) int current, step; public Counter(int startValue, int stepValue) { // (2) set(startValue); setStepValue(stepValue); } public int get() { return current; } // (3) public void set(int value) { current = value; } // (4) public void setStepValue(int stepValue) { step = stepValue; } // (5) }
第5题:
10. interface Foo { int bar(); } 11. public class Sprite { 12. public int fubar( Foo foo) { return foo.bar(); } 13. public void testFoo() { 14. fubar( 15. // insert code here 16.); 17. } 18. } Which code, inserted at line 15, allows the class Sprite to compile?()
第6题:
Given the following class, which statements can be inserted at position 1 without causing the code to fail compilation?() public class Q6db8 { int a; int b = 0; static int c; public void m() { int d; int e = 0; // Position 1 } }
第7题:
Given the following code: public class Person{ int arr[] = new int[10]; public static void main(String a[]) { System.out.println(arr[1]); } } Which statement is correct?()
第8题:
class A { public int getNumber(int a) { return a + 1; } } class B extends A { public int getNumber (int a) { return a + 2 } public static void main (String args) { A a = new B(); System.out.printIn(a.getNumber(0)); } } What is the result? ()
第9题:
public int sum(int a, int b) { return a + b; }
public int sum(long a, long b) { return 0; }
abstract int sum();
private long sum(long a, long b) { return a + b; }
public long sum(long a, int b) { return a + b; }
第10题:
c = b;
c = this.a;
c = this.b;
c = Q4a39.this.a;
c = c;
第11题:
0
1
14
–15
An error at line 3 causes compilation to fail.
An error at line 4 causes compilation to fail.
第12题:
public class Circle implements Shape { private int radius; }
public abstract class Circle extends Shape { private int radius; }
public class Circle extends Shape { private int radius; public void draw(); }
public abstract class Circle implements Shape { private int radius; public void draw(); }
public class Circle extends Shape { private int radius;public void draw() {/* code here */} }
public abstract class Circle implements Shape { private int radius;public void draw() { / code here */ } }
第13题:
class A { protected int method1(int a, int b) { return 0; } } Which two are valid in a class that extends class A?()
第14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15题:
What will be the result of attempting to compile and run the following code?() public class Q6b0c { public static void main(String args[]) { int i = 4; float f = 4.3; double d = 1.8; int c = 0; if (i == f) c++; if (((int) (f + d)) == ((int) f + (int) d)) c += 2; System.out.println(c); } }
第16题:
Given the following code, which method declarations, when inserted at the indicated position, will not cause the program to fail compilation?() public class Qdd1f { public long sum(long a, long b) { return a + b; } // insert new method declaration here }
第17题:
public class X { public static void main (Stringargs) { int a = new int [1] modify(a); System.out.printIn(a[0]); } public static void modify (int a) { a[0] ++; } } What is the result?()
第18题:
public class test( public int aMethod()[ static int i=0; i++; return I; ) public static void main (String args){ test test = new test(); test.aMethod(); int j = test.aMethod(); System.out.printIn(j); ] } What is the result?()
第19题:
Given the following code: public class Person{ static int arr[] = new int[10]; public static void main(String a[]) { System.out.println(arr[1];) } } Which statement is correct?()
第20题:
public abstract class Shape { private int x; private int y; public abstract void draw(); public void setAnchor(int x, int y) { this.x = x; this.y = y; } } Which two classes use the Shape class correctly?()
第21题:
a++;
b++;
c++;
d++;
e++;
第22题:
When compilation some error will occur.
It is correct when compilation but will cause error when running.
The output is zero.
The output is null.
第23题:
When compilation some error will occur.
It is correct when compilation but will cause error when running.
The output is zero.
The output is null.
第24题:
The program runs and prints “0”
The program runs and prints “1”
The program runs but aborts with an exception.
An error “possible undefined variable” at line 4 causes compilation to fail.
An error “possible undefined variable” at line 9 causes compilation to fail.