Saturday, January 2, 2016

Java v3 test answers of 2016

Java v3 test answers of 2016

Find Complete and recently updated Correct Question and answers of Java Test v of Upwork. All Answers updated regularly with new questions. Upwork Java Test v answers of 2016.



Question:* Which statements are true regarding ServletContext Init Parameters in the deployment descriptor?

Answer: • They are set at deployment-time, but accessed at run-time.

Answer: • They are set at deployment-time and can be updated at run-time.

Question:* Which of the following symbols are metacharacters supported by the java.util.regex API?

Answer: • .

Answer: • \

Question:* SQLException has a feature of chaining - identify the right code to execute the same from the following options:

Answer: • catch(SQLException e) { out.println(e.getMessage()); while((e=e.getNextException())!=null) { out.println(e.getMessage()); } }

Question:* What is the result of an attempt to compile and run the given program? public class Test107 { public static void main(String[] args) { System.out.println(test()); } private static int test() { return (true ? null : 0); } }

Answer: • It compiles, but throws NullPointerException at run-time.

Question:* Which of the following methods are members of the Vector class and allow you to input a new element?

Answer: • addElement

Question:* In which class is the notify method defined?

Answer: • Object

Question:* What is the output of the given program? public class Test93 { private int x = 0; public static void main(String[] args) { new Test93().test(); } private int f(int x) { return ++x; } private int g(int y) { return x++; } private void test() { System.out.print( f(x)==f(x) ? "f" : "#" ); System.out.print( g(x)==g(x) ? "g" : "#" ); } }

Answer: • f#

Question:* Which design pattern reduces network traffic by acting as a caching proxy of a remote object?

Answer: • Value Object

Question:* What is the output of the given program? public class Test89 { public static void main(String[] args) { T x = new T("X", null); x.start(); T y = new T("Y", x); y.start(); T z = new T("Z", y); z.start(); } } class T extends Thread { private Thread predecessor; private String name; public T(String name, Thread predecessor) { this.predecessor = predecessor; this.name = name; } public void run() { try { Thread.sleep((int)(Math.random()*89)); System.out.print(name); } catch (InterruptedException ie) { ie.printStackTrace(); } } }

Answer: • any of the following: XYZ, XZY, YXZ, YZX, ZXY, ZYX

Question:* The principal finder method that must be implemented by every entity bean class is:

Answer: • findByPrimaryKey()

Question:* Which option lists Java access modifiers in the right order from the most permissive to the most restrictive?

Answer: • public, protected, <i>no modifier/default/package</i>, private

Question:* What should be the replacement of "//ABC" in the following code? class Krit { String str= new String("OOPS !!! JAVA"); public void KritMethod(final int iArgs) { int iOne; class Bicycle { public void sayHello() { //ABC } } } public void Method2() { int iTwo; } }

Answer: • System.out.print(str);

Question:* Assuming that val has been defined as an int for the code below, which values of val will result in "Test C" being printed? if( val > 4 ) { System.out.println("Test A"); } else if( val > 9 ) { System.out.println("Test B"); } else System.out.println("Test C");

Answer: • val between 0 and 4

Question:* What is the output of the given program? public class Test118 extends _Test118 { { System.out.print("_INIT"); } static { System.out.print("_STATIC"); } Test118() { System.out.print("_CONST"); } public static void main(String[] args) { System.out.print("_MAIN"); new Test118(); } } class _Test118 { _Test118() { System.out.print("_BASE"); } }

Answer: • _STATIC_MAIN_BASE_INIT_CONST

Question:* What will be the output, if the following program is run? public class Test8 { public static void main(String[] args) { System.out.println(Math.sqrt(-4)); } }

Answer: • NaN

Question:* What will be the output of this program? public class Test { public static void main(String args[]) { int a, b; a = 2; b = 0; System.out.println(g(a, new int[] { b })); } public static int g(int a, int b[]) { b[0] = 2 * a; return b[0]; } }

Answer: • 4

Question:* There are three classes named A, B, and C. The class B is derived from class A and class C is derived from B. Which of the following relations are correct for the given classes?

Answer: • Any instance of B is an instance of A.

Question:* What is the output of the given console application? public class Test19 { public static void main(String[] args) { final int X = 9; int[][] a = {{5, 4, 3}, {9, 7, 2}, {1, 6, 8}}; for (int i=0; i<3; i++) { for (int j=0; j<3; j++) { if (a[i][j] == X) break; System.out.print(a[i][j] + "" ""); } } } }

Answer: • 5 4 3 1 6 8

Question:* Which of the following statements is true?

Answer: • public interface RemoteTrain extends java.rmi.Remote

Question:* The JDK comes with a special program that generates skeleton and stub objects that is known as:

Answer: • rmic

Question:* How many objects are created by the following code? Object a, b, c, d, e; e = new Object (); b = a = e; e = new Object ();

Answer: • 2

Question:* Which of these interfaces is the most applicable when creating a class that associates a set of keys with a set of values?

Answer: • Map

Question:* Which of the following is the correct syntax for creating a Session object?

Answer: • HttpSession ses=request.getSession();

Question:* Which statement is true about the given code? public class Test78 { public static void main(String[] args) throws Exception { new JBean().setHeight(1).setWidth(2).setDepth(3).setDensity(9); } } class JBean { private int height, width, depth, density; public JBean setHeight (int h) { this.height = h; return this; } public JBean setWidth (int w) { this.width = w; return this; } public JBean setDepth (int d) { this.depth = d; return this; } public JBean setDensity (int d) { this.density = d; return this; } }

Answer: • The code compiles and runs.

Question:* Choose all valid forms of the argument list for the FileOutputStream constructor shown below:

Answer: • FileOutputStream( File f )

Question:* Which of the following methods should be invoked by the container to get a bean back to its working state?

Answer: • EJBActivate()

Question:* Select all true statements:

Answer: • An abstract class can have non-abstract methods.

Question:* Which option could be used to see additional warnings about code that mixes legacy code with code that uses generics?

Answer: • -Xlint:unchecked

Question:* Assuming the servlet method for handling HTTPGET requests is doGet(HttpServletRequest req, HTTPServletResponse res), how can the request parameter in that servlet be retrieved?

Answer: • String value=req.getParameter("product");

Question:* Which of these is not an event listener adapter defined in the java.awt.event package?

Answer: • ActionAdapter

Question:* What would be the result of compiling and running the following code class? public class Test { public static void main(String args[]) { Test t = new Test(); t.start(); } public void start() { int i = 2; int j = 3; int x = i & j; System.out.println(x); } }

Answer: • The code will compile and print 2.

Question:* Which of the following are the methods of the Thread class?

Answer: • yield()

Question:* What protocol is used by the DatagramSocket class?

Answer: • UDP

Question:* Which statements are true? Select all true statements.

Answer: • A method can be declared synchronized.

Question:* Which exception must a setter of a constrained JavaBean property throw to prevent the property value from changing?

Answer: • PropertyVetoException

Question:* X.509 version 3 specifies which of the following?

Answer: • A format and content for digital certificates.

Question:* What will be the output when this code is compiled and run? public class Test { public Test() { Bar b = new Bar(); Bar b1 = new Bar(); update(b); update(b1); b1 = b; update(b); update(b1); } private void update(Bar bar) { bar.x = 20; System.out.println(bar.x); } public static void main(String args[]) { new Test(); } private class Bar { int x = 10; } }

Answer: • 20 20 20 20

Question:* Which of the following methods can be used for reporting a warning on a Connection object, Statement object & ResultSet object?

Answer: • getWarnings()

Question:* Which of the following are valid ways to define a thread in Java?

Answer: • Create a subclass of java.lang.Thread class

Question:* JDBC is based on:

Answer: • X/Open CLI (Call Level Interface)

Question:* Which of the following statements regarding abstract classes are true?

Answer: • The abstract class may have method implementation.

Question:* Which of the following is the name of the cookie used by Servlet Containers to maintain session information?

Answer: • JSESSIONID

Question:* Which method is called by the servlet container just after the servlet is removed from service?

Answer: • public void destroy() {// code...}

Question:* Which method in the HttpServlet class corresponds to the HTTPPUT method?

Answer: • doPut

Question:* Which of the following illustrates correct synchronization syntax?

Answer: • public synchronized void Process(){}

Question:* The transaction attribute of a bean is set to 'TX_REQUIRES_NEW.' What can be inferred about its behavior?

Answer: • The bean manages its own transaction.

Question:* How many objects are created in the given code? Object x, y, z; x = new Object(); y = new Object();

Answer: • 2

Question:* How does the set collection deal with duplicate elements?

Answer: • The add method returns false if you attempt to add an element with a duplicate value.

Question:* What is the output of the given program? public class Test106 { public static void main(String[] args) { Integer x = 0; Integer y = 0; Integer a = 1000; Integer b = 1000; System.out.println( (a==b) + "; " + (x==y) ); } }

Answer: • false; true

Question:* 1 <libraryPrefix:handlerName parameterNAme="value"> 2 <%=23*counter %> 3 <b>Congratulations!</b> Which of the following is the correct way to complete the code snippet above?

Answer: • </libraryPrefix:handlerName>

Question:* Which of the following transaction modes are supported by Enterprise Java Beans?

Answer: • All of the above

Question:* What is the output of the given program? public class Test120 extends _Test120 { { System.out.print("_INIT"); } static { System.out.print("_STATIC"); } Test120() { System.out.print("_CONST"); } public static void main(String[] args) { System.out.print("_MAIN"); new Test120(); } } class _Test120 { { System.out.print("_BIN"); } static { System.out.print("_START"); } _Test120() { System.out.print("_BASE"); } }

Answer: • _START_STATIC_MAIN_BIN_BASE_INIT_CONST

Question:* Which distributed object technology is most appropriate for systems that consist entirely of Java objects?

Answer: • RMI

Question:* The following code was written to save a handle to an EJBObject named 'bookEJBObject' for an online book shop: javax.ejb.Handle bookHandle = _____________; ObjectOutputStream stream = new ObjectOutputStream(newFileOutputStream(fileName)); stream.writeObject(bookHandle); stream.close(); Which of the following methods should be filled in the blank?

Answer: • bookEJBObject.getHandle()

Question:* Which sequence will be printed when the following program is run? import java.util.*; public class Test { public static void main(String str[]) { List l = new ArrayList(); l.add(''1''); l.add(''2''); l.add(1,''3''); System.out.println(l); } }

Answer: • [1, 3, 2]

Question:* Conventionally, which directory do servlet class files get placed on?

Answer: • WEB-INF\classes

Question:* Which is a proper way to declare and throw exception of class XYException?

Answer: • class XYException extends Exception {} ... throw new XYException();

Question:* Which of the following JDBC methods is used to retrieve large binary objects?

Answer: • getBinaryStream()

Question:* What is the output of the given program? public class Test129 { public static void main(String[] args) { A a = new A2(); B b = new B2(); System.out.println(a.a + "" + b.b); } } class A { int a = 1; } class A2 extends A { int a = 2; } class B { public int b = 1; } class B2 extends B { public int b = 2; }

Answer: • 11

Question:* What exception is thrown by this code, if arr[j]>arr[j+1]: public static void main(String[] args) { int []arr={12,23,43,34,3,6,7,1,9,6}; { int temp; for (int i=0;i<arr.length;i++) { for (int j=0;j<arr.length-i;j++ ) { if (arr[j]>arr[j+1]) { temp=arr[j]; arr[j+1]=arr[j]; arr[j+1]=temp; } } } } for(int i=0; i<arr.length; i++) { System.out.print(arr[i] + " "); } }

Answer: • ArrayIndexOutOfBoundException

Question:* Which of the following is a well-known HTTP port?

Answer: • 80

Question:* What is the output of the given console application? public class Test31 { public static void main(String[] args) { test(); } public static void test() { try { System.out.print("-try"); return; } catch (Exception e) { System.out.print("-catch"); } finally { System.out.print("-finally"); } } }

Answer: • -try-finally

Question:* Which of these interfaces are used by implementations of models for JTable?

Answer: • TableModel

Question:* Which of the following require explicit try/catch exception handling by the programmer?

Answer: • Attempting to open a network socket

Question:* What is the output of the given program? public class Test89 { public static void main(String[] args) { T x = new T(""X"", null); x.start(); T y = new T(""Y"", x); y.start(); T z = new T(""Z"", y); z.start(); } } class T extends Thread { private Thread predecessor; private String name; public T(String name, Thread predecessor) { this.predecessor = predecessor; this.name = name; } public void run() { try { Thread.sleep((int)(Math.random()*89)); System.out.print(name); } catch (InterruptedException ie) { ie.printStackTrace(); } } }

Answer: • Any of the following: XYZ, XZY, YXZ, YZX, ZXY, ZYX

Question:* Which of the following code snippets will take transform input string "2012/06/05" to output string "05 - 06 - 2012"?

Answer: • String dateString = "2012/06/05"; Date date = new SimpleDateFormat("yyyy/MM/dd").parse(dateString); SimpleDateFormat sdf = new SimpleDateFormat("dd - MM - yyyy"); System.out.println(sdf.format(date));

Question:* Which statement is true regarding ServletContext Initialization Parameters in the deployment descriptor?

Answer: • They are accessible by all servlets in a given web application.

Question:* Which of the following statements is true of the HashMap class?

Answer: • It stores information as key/value pairs.

Question:* Which distributed object technology is most appropriate for systems that consist of objects written in different languages and that execute on different operating system platforms?

Answer: • CORBA

Question:* What is the output of the given code? public class Test15 { public static void main(String[] args) { VO a = new VO(2); VO b = new VO(3); swapONE(a, b); print(a, b); swapTWO(a, b); print(a, b); } private static void print(VO a, VO b) { System.out.print(a.toString() + b.toString()); } public static void swapONE(VO a, VO b) { VO tmp = a; a = b; b = tmp; } public static void swapTWO(VO a, VO b) { int tmp = a.x; a.x = b.x; b.x = tmp; } } class VO { public int x; public VO(int x) { this.x = x; } public String toString() { return String.valueOf(x); } }

Answer: • 2332

Question:* What would happen on trying to compile and run the following code? class House { public final void MaintainMethod() { System.out.println("MaintainMethod"); } } public class Building extends House { public static void main(String argv[]) { House h = new House(); h.MaintainMethod(); } }

Answer: • Successful compilation and output of "MaintainMethod" at run time.

Question:* Which of the following code snippets will generate five random numbers between 0 and 200?

Answer: • Random r = new Random(); for (int i = 0; i < 5; i++) { System.out.println(r.nextInt(200)); }

Question:* What will be the output when this code is compiled and run? public class Test { public Test() { Bar b = new Bar(); Bar b1 = new Bar(); update(b); update(b1); b1 = b; update(b); update(b1); } private void update(Bar bar) { bar.x = 20; System.out.println(bar.x); } public static void main(String args[]) { new Test(); } private class Bar { int x = 10; } }

Answer: • 20 20 20 20

Question:* Which class contains a method to create a directory?

Answer: • File

Question:* What is the output of the given program? public class Test130 { public static void main(String[] args) { A a = new A2(); B b = new B2(); System.out.println(a.a + """" + b.b()); } } class A { public int a = 1; } class A2 extends A { public int a = 2; } class B { public int b() { return 1; } } class B2 extends B { public int b() { return 2; } }

Answer: • 12

Question:* Which of the following is the correct syntax for suggesting that the JVM perform garbage collection?

Answer: • System.gc();

Question:* Why can't a Graphics object be created using the following statement? Graphics g = new Graphics();

Answer: • The Graphics class is an abstract class.

Question:* Select all correct statements:

Answer: • Vector is synchronized, ArrayList is not synchronized

Question:* What is the output of the given program? public class Test97 { public static void main(String[] args) { int[][] a = new int[2][2]; System.out.println(a.length); } }

Answer: • 2

Question:* Which of the following is false?

Answer: • A while loop can be used because next () & previous () methods return -1 beyond the resultset.

Question:* Consider the following code: public class Jam { public void apple(int i, String s) { } //ABC } Choose possible valid code replacements of "//ABC" among the choices:

Answer: • public void apple(String s, int i) {}

Question:* RMI allows remote communication between:

Answer: • Java and Java

Question:* Which of the following interfaces makes it possible for Java to save an object to a file and turn it into a data stream?

Answer: • java.io.Serializable

Question:* How many objects are created in the given code? Object x, y, z; x = new Object(); y = new Object()

Answer: • 2

Question:* As part of the type erasure process, when compiling a class or interface that extends a parameterized class or implements a parameterized interface, the compiler may need to create a synthetic method, called a _________.

Answer: • bridge method

Question:* Consider the following code: public static void main(String bicycle[]) { System.out.println(bicycle[0]); } What would be the result if "java TwoTyre one two" is entered in the command line?

Answer: • one

Question:* With regard to the destroy lifecycle method, identify the correct statements about its purpose or about how and when it is invoked.

Answer: • It gives the servlet an opportunity to clean up resources.

Question:* What is the term to describe a situation where two or more threads are blocked forever, waiting for each other?

Answer: • deadlock

Question:* What will be the output of the following code? public class MyTest { public static void main(String[] args) { for (int i=0; i > 10; i+=2) { System.out.println(i); } } }

Answer: • Nothing will be printed.

Question:* Which of the following cannot apply to constructors?

Answer: • Void return type



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