Declaration And Access Control(Computer Science > Java Program ) Questions and Answers
Explanation:-
Answer: Option D. -> This method is accessible from within the class itself and from within all classes defined in the same package as the class itself.Explanation:-
Answer: Option E. -> static void add(int...args){}Explanation:-
Answer: Option D. -> Compilation Error
Question 4. 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 1
Tester();
}
public static void Tester(){ // line 2
System.out.print(this.x); // line 3
}
public static void main(String... args){ // line 4
new Tester();
}
}
public class Tester{
static int x = 4;
public Tester(){
System.out.print(this.x); // line 1
Tester();
}
public static void Tester(){ // line 2
System.out.print(this.x); // line 3
}
public static void main(String... args){ // line 4
new Tester();
}
}
Explanation:-
Answer: Option C. -> Compile error at line 3 (static methods can't invoke this)
Question 5. 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 1
printVariables();
}
public static void printVariables(){
System.out.print(x); // line 2
System.out.print(y); // line 3
}
public static void main(String... args) { // line 4
new Tester();
}
}
public class Tester{
static int x = 4;
int y = 9;
public Tester(){
System.out.print(this.x); // line 1
printVariables();
}
public static void printVariables(){
System.out.print(x); // line 2
System.out.print(y); // line 3
}
public static void main(String... args) { // line 4
new Tester();
}
}
Explanation:-
Answer: Option B. -> Compile error at line 3 (static methods can't make reference to non-static variables)
Question 7. Consider the following two classes declared and defined in two different packages, what can be added in class B to form what considered a correct access to class A from main() method of class B?
package subPackage;
public class A { }
package anotherPackage;
// line 1
public class B{
public static void main(String[] args){
// line 2
}
}
1. At line1 add noting; At line2 add: new A();
2. At line 1 add: import package.*; at line 2 add : new subPackage.A();
3. At line 1 add: import subPackage.*; at line 2 add : new A();
4. At line 1 add: import subPackage.A; at line 2 add : new A();
package subPackage;
public class A { }
package anotherPackage;
// line 1
public class B{
public static void main(String[] args){
// line 2
}
}
1. At line1 add noting; At line2 add: new A();
2. At line 1 add: import package.*; at line 2 add : new subPackage.A();
3. At line 1 add: import subPackage.*; at line 2 add : new A();
4. At line 1 add: import subPackage.A; at line 2 add : new A();