Interfaces and Abstract Classes -Java Programming MCQ Questions and Answers

import java.io.*;
class Chararrayinput 
{
    public static void main(String[] args) 
    {
  String obj  = "abcdef";
        int length = obj.length();
        char c[] = new char[length];
        obj.getChars(0,length,c,0);
        CharArrayReader input1 = new CharArrayReader(c);
        CharArrayReader input2 = new CharArrayReader(c, 0, 3);
        int i;
        try 
        {
while ((i = input1.read()) != -1) 
            {
                System.out.print((char)i);
            }
        } 
        catch (IOException e) 
        {
      // TODO Auto-generated catch block
            e.printStackTrace();
  }
}
}

class Output 
{
    public static void main(String args[]) 
    {
        byte a[] = { 65, 66, 67, 68, 69, 70 };
        byte b[] = { 71, 72, 73, 74, 75, 76 };  
        System.arraycopy(a, 2, b, 1, a.length-2);
        System.out.print(new String(a) + " " + new String(b));
    }
}

import java.io.*;
class files 
{
    public static void main(String args[]) 
    {
        File obj = new File("/java/system");
        System.out.print(obj.getAbsolutePath());
    }
}

class Output
{
    public static void main(String args[])
    {
        String str = "true";
        boolean x = Boolean.valueOf(str);
        System.out.print(x);
    }
}

import java.io.*;
class files 
{
    public static void main(String args[]) 
    {
        File obj = new File("/java/system");
        System.out.print(obj.canWrite());
        System.out.print(" " + obj.canRead());
    }
}

public class BoxDemo
{
    public static <U> void addBox(U u, 
    java.util.List<Box<U>> boxes)
    {
       Box<U> box = new Box<>();
       box.set(u);
       boxes.add(box);
    }
    public static <U> void outputBoxes(java.util.List<Box<U>> boxes) 
    {
        int counter = 0;
        for (Box<U> box: boxes) 
        {
            U boxContents = box.get();
            System.out.println("[" + boxContents.toString() + "]");
            counter++;
        }
    }
    public static void main(String[] args)
    {
        java.util.ArrayList<Box<Integer>> listOfIntegerBoxes = new java.util.ArrayList<>();
        BoxDemo.<Integer>addBox(Integer.valueOf(0), listOfIntegerBoxes);
        BoxDemo.outputBoxes(listOfIntegerBoxes);
    }
}

class Output 
{
    public static void main(String args[]) 
    {
        Integer i = new Integer(257);  
        float x = i.floatValue();
        System.out.print(x);
    }
}