DECLARATION AND ACCESS CONTROL QUIZ

What is the result of compiling and running the following code?class Base{ private Base(){ System.out.print("Base"); }}public class test extends Base{ public test(){ System.out.print("Derived"); } public static void main(String[] args){ new test(); }}

Derived

Exception is thrown at runtime

BaseDerived

Compilation Error

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Choose the correct statementpublic class Circle{ private double radius; public Circle(double radius){ radius = radius; }}

The program has a compilation error because it does not have a main method.

The program has a compilation error because we cannot assign radius to radius.

The program does not compile because Circle does not have a default constructor.

The program will compile, but we cannot create an object of Circle with a specified radius. The object will always have radius 0.

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What is the result of compiling and running the following code?public class Tester{static int x = 4;public Tester(){System.out.print(this.x); // line 1Tester();}public static void Tester(){ // line 2System.out.print(this.x); // line 3}public static void main(String... args){ // line 4new Tester();}}

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Compile error at line 4 (invalid argument type for method main )

Compile error at line 3 (static methods can't invoke this)

Compile error at line 1 (static x must be only accessed inside static methods)

Compile error at line 2 (constructors can't be static)

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You have the following code in a file called Test.javaclass Base{ public static void main(String[] args){ System.out.println("Hello"); }}public class Test extends Base{}What will happen if you try to compile and run this?

Compiles and runs printing

It will fail to compile.

Runtime error

Compiles and runs with no output.

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What will be the output?public class Test{ public static void main(String[] args){ String value = "abc"; changeValue(value); System.out.println(value); } public static void changeValue(String a){ a = "xyz"; }}

xyz

Compilation fails

Compilation clean but no output

None of these

abc

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Name the keyword that makes a variable belong to a class, rather than being defined for each instance of the class.

volatile

abstract

static

native

final

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What is the result of compiling and running the following code?public class Tester{static int x = 4;int y = 9; public Tester(){System.out.print(this.x); // line 1printVariables();}public static void printVariables(){System.out.print(x); // line 2System.out.print(y); // line 3}public static void main(String... args) { // line 4new Tester();}}

Compile error at line 4 (invalid argument type for method main)

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Compile error at line 2 (must access x by writing Tester.x)

Compile error at line 1 (static x must be only accessed inside static methods)

Compile error at line 3 (static methods can't make reference to non-static variables)

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Determine output:class A{{System.out.print("b1 ");}public A(){System.out.print("b2 ");}}class B extends A{static{System.out.print("r1 ");}public B(){System.out.print("r2 ");}{System.out.print("r3 ");}static{System.out.print("r4 ");}}public class Test extends B{public static void main(String[] args){System.out.print("pre ");new Test();System.out.println("post ");}}

Compilation fail

r1 r4 pre b1 b2 r3 r2 post

pre r1 r4 b1 b2 r2 r3 post

r1 r4 pre b1 b2 post

r1 r4 pre b1 b2 post r3 r2

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A method within a class is only accessible by classes that are defined within the same package as the class of the method. Which one of the following is used to enforce such restriction?

Do not declare the method with any accessibility modifiers.

Declare the method with the keyword protected.

Declare the method with the keyword public.

Declare the method with the keyword private.

Declare the method with the keyword public and private.

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Which statements are most accurate regarding the following classes?class A{ private int i; protected int j;}class B extends A{ private int k; protected int m;}

An object of B contains data fields j, k, m.

An object of B contains data fields j, m.

An object of B contains data fields k, m.

An object of B contains data fields i, j, k, m.

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