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1题:
类Test定义如下,将下列哪个方法插入③行处是不合法的( )?
① public class Test{
② public float Method(float a,float B) { }
③ ______
④ }
A.public float Method(float a,float b,float C) { }
B.public float Method(float c,float d){ }
C.public int Method(int a,int B) { }private float Method(int a,int b,int C) { }
D.private float Method(int a,int b,int C) { }
第2题:
1. class A { 2. public int getNumber(int a) { 3. return a + 1; 4. } 5. } 6. 7. class B extends A { 8. public int getNumber (int a) { 9. return a + 2 10. } 11. 12. public static void main (String args[]) { 13. A a = new B(); 14. System.out.printIn(a.getNumber(0)); 15. } 16. } What is the result?()
第3题:
interface DeclareStuff{ public static final int EASY = 3; void doStuff(int t); } public class TestDeclare implements DeclareStuff { public static void main(String [] args) { int x=5; new TestDeclare().doStuff(++x); } void doStuff(int s) { s += EASY + ++s; System.out.println(”s “ + s); } } What is the result?()
第4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5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6题:
public class MethodOver { public void setVar (int a, int b, float c) { } } Which two overload the setVar method?()
第7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8题:
现有: 1. interface Altitude { 2. //insert code here 3. } 和4个声明: int HIGH = 7; public int HIGH = 7; abstract int HIGH = 7; interface int HIGH = 7; 分别插入到第2行,有多少行可以编译?()
第9题:
int doStuff() { return 42; }
int doStuff(int x) { return 42; }
Foo doStuff(int x) { return new Foo(); }
SuperFoo doStuff(int x) { return new Foo(); }
第10题:
Definition a.
Definition b.
Definition c.
Definition d.
Definition e.
第11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12题:
private void set Var(int a, float c, int b) {}
protected void set Var(int a, int b, float c) {}
public int set Var(int a, float c, int b) {return a:}
public int set Var(int a, int b, float c) {return a:}
protected float set Var(int a, int b, float c) {return c:}
第13题:
有一个接口定义如下,下列选项中实现了该接口并且不是抽象的是 interface A { int method1(int i); int method2(int j); }
A.class B implements A { int method 1(){} int method 2(){} }
B.class B { int method 1(int i){} int method 2(int j){} }
C.class B implements A { int method 1(int i){} int method 2(int j){} }
D.class B extends A { int method 2(int j){} int method 1(int j){} }
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:
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16题:
Given the following interface definition, which definitions are valid?() interface I { void setValue(int val); int getValue(); } DEFINITION a: (a) class a extends I { int value; void setValue(int val) { value = val; } int getValue() { return value; } } DEFINITION b: (b) interface b extends I { void increment(); } DEFINITION c: (c) abstract class c implements I { int getValue() { return 0; } abstract void increment(); } DEFINITION d: (d) interface d implements I { void increment(); } DEFINITION e: (e) class e implements I { int value; public void setValue(int val) { value = val; } }
第17题:
1. class SuperFoo { 2. SuperFoo doStuff(int x) { 3. return new SuperFoo(); 4. } 5. } 6. 7. class Foo extends SuperFoo { 8. //insert code here 9. } 下面哪三项分别插入到第8行,可以编译?()
第18题:
现有: 1. interface Animal { 2. void eat(); 3. } 4. 5. // insert code here 6. 7. public class HouseCat extends Feline { 8. public void eat() { } 9. } 和五个声明: abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat(); } abstract class Feline implements Animal { public void eat(); } abstract class Feline implements Animal { public void eat() { } } abstract class Feline implements Animal { abstract public void eat(); } 分别插入到第5行,有几个可以通过编译?()
第19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20题:
Private void setVar (int a, float c, int b) { }
Protected void setVar (int a, int b, float c) { }
Public int setVar (int a, float c, int b) (return a;)
Public int setVar (int a, int b, float c) (return a;)
Protected float setVar (int a, int b, float c) (return c;)
第21题:
Line 26 prints “a” to System.out.
Line 26 prints „b” to System.out.
An exception is thrown at line 26 at runtime.
Compilation of class A will fail due to an error in line 6.
第22题:
0
1
2
3
4
第23题:
s 14
s 16
s 10
Compilation fails.
An exception is thrown at runtime.