Hello, I want some help for those questions for Java language. Please give me so

Question

Hello, I want some help for those questions for Java language. Please give me some examples to let me understand :

ArrayList Section

write code to create and fill an ArrayList of a given type. ( give example )

Modularity Section

write a method and its calling code with proper parm passing, return value and visibility. ( give example )

Inheritance Section

True or False Questions

T / F A super class constructor must execute to completion before any statements in its sub class constructor can be executed.

T / F You do not have to call a super class constructor explicitly.
T / F Java allows you to inherit directly from only one class, but you may implement multiple interfaces.

T / F When declaring a class as a super class, you should never declare your fields private; use protected instead.

T / F An interface is often thought of as a form of a very restricted super class.

T / F An interface allows us to guarantee that any class that implements it will have the behaviors specified by the interface. It is a contract.

T / F A sub class is not required to override any methods it inherits from its super class.

T / F Instance fields should be initialized in the constructor(s) of the class they were declared in if at all possible.

T / F The two benefits of inheritance are code re-use and polymorphic behavior.

Explanation / Answer

import java.util.*;  

class TestArrayList{  

public static void main(String args[]){  

  ArrayList<String> fruits=new ArrayList<String>();//Creating arraylist  

fruits.add("Orange");//Adding object in arraylist  

fruits.add("Apple");  

fruits.add("Pear");  

fruits.add("Cherry");  

  //Traversing list through Iterator  

  Iterator itr=fruits.iterator();  

  while(itr.hasNext()){  

   System.out.println(itr.next());  

  }  

}  

}

output:

Orange
Apple
Pear
Cherry

class TestMaxFunction {

public static void main(String[] args) {
int x= 56;
int y = 49;
int z = MaxFunction(x,y);
System.out.println("Maximum = " + z);
}

// returns the maximum of two numbers
public static int MaxFunction(int num1, int num2) {
int max;
if (num1 > num2)
max = num1;
else
max = num2;

return max;
}
}

output:

Maximum = 56

rue or False Questions

T A super class constructor must execute to completion before any statements in its sub class constructor can be executed.

T You do not have to call a super class constructor explicitly.
T Java allows you to inherit directly from only one class, but you may implement multiple interfaces.

F When declaring a class as a super class, you should never declare your fields private; use protected instead.

F An interface is often thought of as a form of a very restricted super class.

T An interface allows us to guarantee that any class that implements it will have the behaviors specified by the interface. It is a contract.

F A sub class is not required to override any methods it inherits from its super class.

T Instance fields should be initialized in the constructor(s) of the class they were declared in if at all possible.

T The two benefits of inheritance are code re-use and polymorphic behavior.

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