Tag: technology

Questions Related to technology

A class games.cards.Poker is correctly defined in the jar file Poker.jar. A user wants to execute the main method of Poker on a UNIX system using the command: java games.cards.Poker What allows the user to do this? A. put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java B. put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java/.jar C. Put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java/Poker.jar D. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuff/java E. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuffijava/.jar F. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuff/java/Poker.jar

technology programming languages

  1. A

  2. B

  3. C

  4. D

  5. E

  6. F

Show answer
Correct Option: C

What is the result of compiling and running this program? class Clove{ void quality(Clove m){ System.out.println("Clove is nice"); } } class Mint extends Clove{ void quality(Mint c){ System.out.println("Mint is ok"); } } class Sage extends Mint{ void quality(Sage h){ System.out.println("Sage is average"); } } public class Test{ public static void main(String[] args){ Clove h = new Sage(); Mint c = new Sage(); c.quality(h); } }
technology programming languages

  1. prints "Clove is nice"

  2. prints "Mint is ok"

  3. prints "Sage is average"

  4. Class cast Exception at runtime.

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Correct Option: A

What will this program print out ? class Base{ int value = 0; Base(){ addValue(); } void addValue(){ value += 10; } int getValue(){ return value; } } class Derived extends Base{ Derived(){ addValue(); } void addValue(){ value += 20; } } public class Test { public static void main(String[] args){ Base b = new Derived(); System.out.println(b.getValue()); } }
technology programming languages

  1. 10

  2. 20

  3. 30

  4. 40

Show answer
Correct Option: D

Given classes defined in two different files: 1. package util; 2. public class BitUtils { 3. private static void process(byte[] b) { } 4. } 1. package app; 2. public class SomeApp { 3. public static void main(String[] args) { 4. byte[] bytes = new byte[256]; 5. // insert code here 6. } 7. } What is required at line 5 in class SomeApp to use the process method of BitUtils?
technology programming languages

  1. process(bytes);

  2. BitUtils.process(bytes);

  3. app.BitUtils.process(bytes);

  4. util.BitUtils.process(bytes);

  5. import util.BitUtils. *; process(bytes);

  6. SomeApp cannot use the process method in BitUtils.

Show answer
Correct Option: F

class Abc { int i=initialize(369); int j=initialize(); public int initialize() { return 318; } public void initialize(int i) { this.i=i; } public static void main(String a[]) { Abc abc=new Abc(); System.out.println("i="+abc.i); abc.initialize(369); System.out.println("after i="+abc.i); System.out.println("j="+abc.j); } }

technology programming languages

  1. Error: Non static method intialize cannot accessed from static context main

  2. Error: Method initialize is already defined

  3. i=0 after i=369 j=318

  4. Error: incompatible types

Show answer
Correct Option: D

Given: 1. public class Threads4 { 2. public static void main (String[] args) { 3. new Threads4().go(); 4. } 5. public void go() { 6. Runnable r = new Runnable() { 7. public void run() { 8. System.out.print(”foo”); 9. } 10. }; 11. Thread t = new Thread(r); 12. t.start(); 13. t.start(); 14. } 15. } What is the result?
technology programming languages

  1. Compilation fails.

  2. An exception is thrown at runtime.

  3. The code executes normally and prints ‘foo”.

  4. The code executes normally, but nothing is printed.

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Correct Option: B

Given classes defined in two different files: 1. package util; 2. public class BitUtils { 3. public static void process(byte[]) { /* more code here */ } 4. } 1. package app; 2. public class SomeApp { 3. public static void main(String[] args) { 4. byte[] bytes = new byte[256]; 5. // insert code here 6. } 7. } What is required at line 5 in class SomeApp to use the process method of BitUtils?
technology programming languages

  1. process(bytes);

  2. BitUtils.process(bytes);

  3. util.BitUtils.process(bytes);

  4. SomeApp cannot use methods in BitUtils.

  5. import util.BitUtils.*; process(bytes);

Show answer
Correct Option: C

Given: 11. // insert code here 12. private N min, max; 13. public N getMin() { return min; } 14. public N getMax() { return max; } 15. public void add(N added) { 16. if (min == null || added.doubleValue() max.doubleValue()) 19. max = added; 20. } 21. } Which two, inserted at line 11, will allow the code to compile? (Choose two.)
technology programming languages

  1. public class MinMax> {

  2. public class MinMax extends Number> {

  3. public class MinMax {

  4. public class MinMax {

  5. public class MinMax extends Object> {

  6. public class MinMax {

Show answer
Correct Option: D,F

class Abc { static { System.out.print("Static block "); display(); } public void display() { System.out.print("Display block "); } public static void main(String a[]) { System.out.print("Starting of Main block "); Abc abc=new Abc(); System.out.print("In the Main block "); abc.display(); } }

technology programming languages

  1. Starting of Main block Static block In the Main block Display block

  2. Static block Display block Starting of Main block In the Main block Display block

  3. Error: Non static method cannot accessed from static context

  4. Starting of Main block In the Main block Display block

Show answer
Correct Option: B

Given: classA {} class B extends A {} class C extends A {} class D extends B {} Which three statements are true? (Choose three.)

technology programming languages

  1. The type List is assignable to List.

  2. The type List is assignable to List>.

  3. The type List is assignable to List extends B>.

  4. The type List extends A> is assignable to List.

  5. The type List is assignable to any List reference.

  6. The type List extends B> is assignable to List extends A>.

Show answer
Correct Option: B,C,F