单选题public class Mycircle { public double radius； public double diameter； public void setRadius（double radius） this.radius = radius； this.diameter= radius * 2； } public double getRadius（） { return radius； } Which statement is true？（）A The Mycircle class is fully encapsulated.B The diameter of a given MyCircle is guaranteed to be twice its radius.C Lines 6 and 7 should be in a synchronized block to ensure encapsulation.D The radius of a MyCircle object can be set without affecting its diameter.
单选题
public class Mycircle { public double radius； public double diameter； public void setRadius（double radius） this.radius = radius； this.diameter= radius * 2； } public double getRadius（） { return radius； } Which statement is true？（）
A
The Mycircle class is fully encapsulated.
B
The diameter of a given MyCircle is guaranteed to be twice its radius.
C
Lines 6 and 7 should be in a synchronized block to ensure encapsulation.
D
The radius of a MyCircle object can be set without affecting its diameter.
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多选题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？（）Apublic class Circle implements Shape { private int radius； }Bpublic abstract class Circle extends Shape { private int radius； }Cpublic class Circle extends Shape { private int radius； public void draw（）； }Dpublic abstract class Circle implements Shape { private int radius； public void draw（）； }Epublic class Circle extends Shape { private int radius；public void draw（） {/* code here */} }Fpublic abstract class Circle implements Shape { private int radius；public void draw（） { / code here */ } }
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单选题class super { public float getNum（） {return 3.0f；} } public class Sub extends Super { } Which method， placed at line 6， will cause a compiler error？（）A Public float getNum（） {return 4.0f； }B Public void getNum （）{}C Public void getNum （double d）{}D Public double getNum （float d） {retrun 4.0f； }
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单选题Which will declare a method that is available to all members of the same package and can be referenced without an instance of the class？（）A Abstract public void methoda（）；B Public abstract double methoda（）；C Static void methoda（double d1）{}D Public native double methoda（） {}E Protected void methoda（double d1） {}
单选题Which will declare a method that is available to all members of the same package and be referenced without an instance of the class？（）A abstract public void methoda （）；B public abstract double inethoda （）；C static void methoda （double dl） {}D public native double methoda （） {}E protected void methoda （double dl） {}
单选题public class Mycircle { public double radius； public double diameter； public void setRadius（double radius） this.radius = radius； this.diameter= radius * 2； } public double getRadius（） { return radius； } Which statement is true？（）A The Mycircle class is fully encapsulated.B The diameter of a given MyCircle is guaranteed to be twice its radius.C Lines 6 and 7 should be in a synchronized block to ensure encapsulation.D The radius of a MyCircle object can be set without affecting its diameter.
多选题1. public class OuterClass { 2. private double d1 = 1.0； 3. // insert code here 4. } Which two are valid if inserted at line 3？（）Astatic class InnerOne { public double methoda（） { return d1； } }Bstatic class InnerOne { static double methoda（） { return d1； } }Cprivate class InnerOne { public double methoda（） { return d1； } }Dprotected class InnerOne { static double methoda（） { return d1； } }Epublic abstract class InnerOne { public abstract double methoda（）； }
多选题public class OuterClass { private double d1 1.0； //insert code here } You need to insert an inner class declaration at line2. Which two inner class declarations are valid？（）Astatic class InnerOne { public double methoda（） {return d1；} }Bstatic class InnerOne { static double methoda（） {return d1；} }Cprivate class InnerOne { public double methoda（） {return d1；} }Dprotected class InnerOne { static double methoda（） {return d1；} }Epublic abstract class InnerOne { public abstract double methoda（）； }