Compilation succeeds.
An exception is thrown.
Compilation fails because of an error at line 2.
Compilation fails because of an error at line 6.
第1题:
1. interface DoStuff2 { 2. float getRange(int low, int high); } 3. 4. interface DoMore { 5. float getAvg(int a, int b, int c); } 6. 7. abstract class DoAbstract implements DoStuff2, DoMore { } 8. 9. class DoStuff implements DoStuff2 { 10. public float getRange(int x, int y) { return 3.14f; } } 11. 12. interface DoAll extends DoMore { 13. float getAvg(int a, int b, int c, int d); } What is the result?()
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:
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4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?()
第5题:
现有: 1. abstract class Color2 { 2. //insert code here 3. } 4. 5. public class Blue2 extends Color2 { 6.public String getRGB() { return "blue"; } 7. } 和4个声明: public abstract String getRGB(); abstract String getRGB(); private abstract String getRGB(); protected abstract String getRGB(); 分别插入到第2行,有多少行可以编译?()
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:
abstract class abstrctIt { abstract float getFloat (); } public class AbstractTest extends AbstractIt { private float f1= 1.0f; private float getFloat () {return f1;} } What is the result? ()
第8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:
ClassOne.java: 1. package com.abe.pkg1; 2. public class ClassOne { 3. private char var = ‘a’; 4. char getVar() { return var; } 5. } ClassTest.java: 1. package com.abe.pkg2; 2. import com.abc.pkg1.ClassOne; 3. public class ClassTest extends ClassOne { 4. public static void main(String[] args) { 5. char a = new ClassOne().getVar();6. char b = new ClassTest().getVar(); 7. } 8. } What is the result?()