Quiz Time

[ani548]

Hi All,

I am really cherished to be a part of this community.

Thank You.
Anish George

[sukatoa]

Here is another one.. it is compilable.

public class Change {
    public static void main(String args[]) {
        System.out.println(1.00 - 0.60);
    }
}

What should be the specific output?

[sukatoa]

Hello ani548,

Welcome to Java Forums. :)

[Zosden]

Try to guess what this would print out

/**
 * @(#)Quiz.java
 *
 *
 * @author 
 * @version 1.00 2008/5/8
 */


public class Quiz 
{
	Rectangle rectangle1;
	Rectangle rectangle2;
	Rectangle rectangle3;
	Rectangle rectangle4;

    public Quiz() 
    {
    	rectangle1 = new Rectangle();
		rectangle2 = new Rectangle();
		rectangle3 = new Rectangle();
		rectangle4 = new Rectangle();
		System.out.println("Test 1");
		System.out.println(this.toString());
	
    	rectangle1.setLength(10);
    	rectangle1.setWidth(5);
    	System.out.println("Test 2");
    	System.out.println(this.toString());
    	
    	rectangle2 = rectangle1;
    	rectangle2.setWidth(6);
    	rectangle2.setLength(6);
    	System.out.println("Test 3");
    	System.out.println(this.toString());
    	
    	rectangle3 = (Rectangle)rectangle2.clone();
    	rectangle3.setWidth(10);
    	rectangle3.setLength(14);
    	System.out.println("Test 4");
    	System.out.println(this.toString());
    	
    	rectangle4 = (Rectangle)rectangle3.clone();
    	rectangle3 = rectangle2;
    	System.out.println("Test 5");
    	System.out.println(this.toString());
    }
    
    public String toString()
    {
    	String temp  = "Rectangle 1: " + "\n" + rectangle1.toString() + "\n" + "\n";
    	temp += "Rectangle 2: " + "\n" + rectangle2.toString() + "\n" + "\n";
    	temp += "Rectangle 3: " + "\n" + rectangle3.toString() + "\n" + "\n";
    	temp += "Rectangle 4: " + "\n" + rectangle4.toString() + "\n" + "\n";
    	return temp;
    }
    
    public static void main(String[] args)
    {
    	Quiz quiz = new Quiz();
    }
    
}

/**
 * @(#)Rectangle.java
 *
 *
 * @author 
 * @version 1.00 2008/5/8
 */


public class Rectangle 
{
	private int length;
	private int width;
	private int area;
	
    public Rectangle() 
    {
		length = 1;
		width = 1;
		this.calcArea();	
    }
    
    private void calcArea()
    {
    	area = length * width;
    }
    
    public int getLength()
    {
    	return length;
    }
    
    public void setLength(int aLength)
    {
    	length = aLength;
    	this.calcArea();
    }
    
    public int getWidth()
    {
    	return width;
    }
    
    public void setWidth(int aWidth)
    {
    	width = aWidth;
    	this.calcArea();
    }
    
    public Object clone()
    {
    	Rectangle rectangle = new Rectangle();
    	rectangle.setLength(length);
    	rectangle.setWidth(width);
    	return rectangle;
    }
    
    public String toString()
    {
    	String temp = "Area = " + area;
    	temp += "\n" + "length = " + length;
    	temp += "\n" + "width = " + width;
    	return temp;
    }
}

[rjuyal]

@

public class Change {
    public static void main(String args[]) {
        System.out.println(1.00 - 0.60);
    }
}

0.39999999999999999999 :confused:
Post if the answer is Correct


@ani

What about introducing yourself

[rjuyal]

please split your question

keep the catching part only, please :)

[sukatoa]

@ rjuyal... actually it is acceptable. but try to compile and run. it should be .4

I expect that one, but that maybe at

System.out.println(2.00 - 1.10);

It is something about the rules for converting double values to strings, which are specified by the documentation for Double.toString.

[sukatoa]

Here is another one,

public class test{

    private test(Object o) {
        System.out.println("Noob");
    }
    private test(double[] dArray) {
        System.out.println("Java Programmer");
    }
    public static void main(String[] args) {
        System.out.print("I am a ");
        new test(null); 
    }
}

Before you attempt to compile and run it, just guess what should be the output.....

[Zosden]

I am a noob

[sukatoa]

Now, try to compile it,.....

I really don't know what's the real/most specific reason for that it prints

I am a Java Programmer.

For me, it seeks first to the most specific constructor that fits to the values passed. since Object is the most used in every built-In class, that one may (for me) first be compared.
Now, it tries to seek the other constructor that may fit the value passed, since an array can be set as null, that constructor was choosen to receive such value. (null)

If there is another explanation, please let me know....

[fireball2008]

YES for sure

[rjuyal]

what is YES for?

[Zosden]

Don't forget guys about my quiz.

[sukatoa]

@ Zosden

I can't exactly predict what should be the output for that....

BIG LOL im running out of RAM

Just a piece of code from it. or a method.

[Eranga]

Yes Zosden, keep your question short and sweet. :)

[Eranga]

If there is another explanation, please let me know....

Basically Object is the root of the class hierarchy. Every class has a Object as a superclass. So any objects implements the method of this class. So why we get the output as,

I am a Java Programmer

arrays also included in this way, and array can be initialized as null.

See the difference with the following code.

public class test{

    private test(Object o) {
        System.out.println("Noob");
    }
    private test(int value) {
        System.out.println("Java Programmer");
    }
    public static void main(String[] args) {
        System.out.print("I am a ");
        new test(null); 
    }
}

[Eranga]

Here is a simple one again.

What's the output of the following line of code.

System.out.println((String)'Java');

[sanjeevtarar]

Hello All,
----------------

Compile time error......

[Eranga]

What type of? and what the reason?

[sanjeevtarar]

What type of? and what the reason?

Because you can put only single character in '......', you are putting string into '......'.