Tag: technology

What will happen when you attempt to compile and run the following code? interface MyInterface { } public class MyInstanceTest implements MyInterface { static String s; public static void main(String args[]) { MyInstanceTest t = new MyInstanceTest(); if(t instanceof MyInterface) { System.out.println("I am true interface"); } else { System.out.println("I am false interface"); } if(s instanceof String) { System.out.println("I am true String"); } else { System.out.println("I am false String"); } } }

What will happen when you attempt to compile and run the following code? class MyThread extends Thread { public void run() { System.out.println("MyThread: run()"); } public void start() { System.out.println("MyThread: start()"); } } class MyRunnable implements Runnable { public void run() { System.out.println("MyRunnable: run()"); } public void start() { System.out.println("MyRunnable: start()"); } } public class MyTest { public static void main(String args[]) { MyThread myThread = new MyThread(); MyRunnable myRunnable = new MyRunnable(); Thread thread = new Thread(myRunnable); myThread.start(); thread.start(); } }

Given the following code, what will be the output? class Value { public int i = 15; } public class Test { public static void main(String argv[]) { Test t = new Test(); t.first(); } public void first() { int i = 5; Value v = new Value(); v.i = 25; second(v, i); System.out.println(v.i); } public void second(Value v, int i) { i = 0; v.i = 20; Value val = new Value(); v = val; System.out.println(v.i + " " + i); } }

What will happen when you attempt to compile and run the following code? class MyParent { int x, y; MyParent(int x, int y) { this.x = x; this.y = y; } public int addMe(int x, int y) { return this.x + x + y + this.y; } public int addMe(MyParent myPar) { return addMe(myPar.x, myPar.y); } } class MyChild extends MyParent { int z; MyChild (int x, int y, int z) { super(x,y); this.z = z; } public int addMe(int x, int y, int z) { return this.x + x + this.y + y + this.z + z; } public int addMe(MyChild myChi) { return addMe(myChi.x, myChi.y, myChi.z); } public int addMe(int x, int y) { return this.x + x + this.y + y; } } public class MySomeOne { public static void main(String args[]) { MyChild myChi = new MyChild(10, 20, 30); MyParent myPar = new MyParent(10, 20); int x = myChi.addMe(10, 20, 30); int y = myChi.addMe(myChi); int z = myPar.addMe(myPar); System.out.println(x + y + z); } }

What will be the result of executing the following code? 1. boolean a = true; 2. boolean b = false; 3. boolean c = true; 4. if (a == true) 5. if (b == true) 6. if (c == true) System.out.println("Some things are true in this world"); 7. else System.out.println("Nothing is true in this world!"); 8. else if (a && (b = c)) System.out.println("It's too confusing to tell what is true and what is false"); 9. else System.out.println("Hey this won't compile");

What will be the result of executing the following code? // Filename; SuperclassX.java package packageX; public class SuperclassX { protected void superclassMethodX() { } int superclassVarX; } // Filename SubclassY.java 1. package packageX.packageY; 2. 3. public class SubclassY extends SuperclassX 4. { 5. SuperclassX objX = new SubclassY(); 6. SubclassY objY = new SubclassY(); 7. void subclassMethodY() 8. { 9. objY.superclassMethodX(); 10. int i; 11. i = objY.superclassVarX; 12. } 13. }