float getVar() { return x; }
public float getVar() { return x; }
public double getVar() { return x; }
protected float getVar() { return x; }
public float getVar(float f) { return f; }
第1题:
1. class Super { 2. public float getNum() { return 3.0f; } 3. } 4. 5. public class Sub extends Super { 6. 7. } Which method, placed at line6, causes compilation to fail?()
第2题:
Given: 1. public class Method Over { 2. public void set Var (int a, int b, float c) { 3. } 4. } Which two overload the set Var method()?
第3题:
类A定义如下: class A { private int x=10; int getx() { return x;} } class B extends A { private int x=15; //需要覆盖getx()方法 } 在下述方法中可以在类B中覆盖getx()方法的是 ( )
A.int getx(){…}
B.int getx(float f){…}
C.float getx(){…}
D.double getx(float f){…}
第4题:
1. public class X ( 2. public object m () { 3. object o = new float (3.14F); 4. object [] oa = new object [1]; 5. oa[0]= o; 6. o = null; 7. return oa[0]; 8. } 9. } When is the float object created in line 3, eligible for garbage collection?()
第5题:
现有: 1. class Synapse { 2. protected int gap() { return 7; } 3. } 4. 5. class Creb extends Synapse { 6. // insert code here 7. } 分别插入到第 6 行,哪三行可以编译?()
第6题:
1. abstract class AbstractIt { 2. abstract float getFloat(); 3. } 4. public class AbstractTest extends AbstractIt { 5. private float f1 = 1.0f; 6. private float getFloat() { return f1; } 7. } What is the result?()
第7题:
1. class Over{ 2. int doIt(long x) { return 3;} 3. } 4. 5. class Under extends Over{ 6. //insert code here 7. } 和四个方法: short doIt(int y) {return 4;} int doIt(long x,long y){return 4;} private int doIt(Short y){ return 4;} protected int doIt(long x){return 4;} 分别插入到第6行,有几个可以通过编译?()
第8题:
1. class BaseClass { 2. private float x = 1.of; 3. protected float getVar() { return x; } 4. } 5. class SubClass extends BaseClass { 6. private float x = 2.Of; 7. // insert code here 8. } Which two are valid examples of method overriding when inserted at line 7?()
第9题:
class BaseClass{ private float x= 1.0f; protected void setVar (float f) {x = f;} } class SubClass extends BaseClass { private float x = 2.0f; //insert code here } Which two are valid examples of method overriding?()
第10题:
class BaseClass{ private float x= 1.0f; protected void setVar (float f) {x = f;} } class SubClass exyends BaseClass { private float x = 2.0f; //insert code here 8. } Which two are valid examples of method overriding?()