JAVA QUESTIONS QUESTION: 1 Given the code fragment: int [] [] array2D = {{0, 1, 2}, {3, 4, 5, 6}}; system.out.print (array2D[0].length+ "" ); system.out.print(array2D[1].getClass().isArray() + ""); system.out.println (array2D[0][1]); What is the result? A. 3false1 B. 2true3 C. 2false3 D. 3true1 E. 3false3 F. 2true1 G. 2false1 QUESTION: 2 View the exhibit: public class Student { public String name = ""; public int age = 0; public String major = "Undeclared"; public boolean fulltime = true; public void display() { System.out.println("Name: " + name + " Major: " + major); } public boolean isFullTime() { return fulltime; } } Given: Public class TestStudent { Public static void main(String[] args) { Student bob = new Student (); Student jian= new Student(); bob.name = "Bob"; bob.age = 19; jian = bob; jian.name = "Jian"; System.out.println("Bob's Name: " + bob.name); }} What is the result when this program is executed? A. Bob's Name: Bob B. Bob's Name: Jian C. Nothing prints D. Bob’s name QUESTION: 3 Given the code fragment: String valid = "true"; if (valid) System.out.println (“valid”); else system.out.println ("not valid"); What is the result? A. Valid B. not valid C. Compilation fails D. An IllegalArgumentException is thrown at run time QUESTION: 4 Given: public class ScopeTest { int z; public static void main(String[]args){ ScopeTest myScope = new ScopeTest(); int z = 6; System.out.println(z); myScope.doStuff(); System.out.println(z); System.out.println(myScope.z); } void doStuff() { int z = 5; doStuff2(); System.out.println(z); } void doStuff2() { z=4; } } What is the result? A. 6 5 6 4 B. 6 5 5 4 C. 6 5 6 6 D. 6 5 6 5 QUESTION: 5 Which two are valid instantiations and initializations of a multi dimensional array? A. int [] [] array 2D = { { 0, 1, 2, 4} {5, 6}}; B. int [] [] array2D = new int [2] [2]; array2D[0] [0] = 1; array2D[0] [1] = 2; array2D[1] [0] = 3; array2D[1] [1] = 4; C. int [] [] [] array3D = {{0, 1}, {2, 3}, {4, 5}}; D. int [] [] [] array3D = new int [2] [2] [2]; array3D [0] [0] = array; array3D [0] [1] = array; array3D [1] [0] = array; array3D[0] [1] = array; E. int [] [] array2D = {0, 1}; QUESTION: 6 An unchecked exception occurs in a method dosomething() Should other code be added in the dosomething() method for it to compile and execute? A. The Exception must be caught B. The Exception must be declared to be thrown. C. The Exception must be caught or declared to be thrown. D. No other code needs to be added. QUESTION: 7 Given the code fragment: int b = 4; b -- ; System.out.println (-- b); System.out.println(b); What is the result? A. 2 2 B. 1 2 C. 3 2 D. 3 3 QUESTION: 8 Given the code fragment: interface SampleClosable { public void close () throws java.io.IOException; } Which three implementations are valid? A. public class Test implements SampleCloseable { Public void close () throws java.io.IOException { / / do something } } B. public class Test implements SampleCloseable { Public void close () throws Exception { / / do something } } C. public class Test implementations SampleCloseable { Public void close () throws Exception { / / do something } } D. public class Test extends SampleCloseable { Public void close () throws java.IO.IOException { / / do something } } QUESTION: 9 Given the code fragment: Int [] [] array = {{0}, {0, 1}, {0, 2, 4}, {0, 3, 6, 9}, {0, 4, 8, 12, 16}}; Systemout.printIn(array [4] [1]); System.out.printIn (array) [1][4]); int [] [] array = {{0}, {0, 1}, {0, 2, 4}, {0, 3, 6, 9}, {0, 4, 8, 12, 16}}; System.out.println(array [4][1]); System.out.println(array) [1][4]); What is the result? A. 4 Null B. Null 4 C. An IllegalArgumentException is thrown at run time D. 4 An ArrayIndexOutOfBoundException is thrown at run time QUESTION: 10 Given: public class DoCompare1 { public static void main(String[] args) { String[] table = {"aa", "bb", "cc"}; for (String ss: table) { int ii = 0; while (ii < table.length) { System.out.println(ss + ", " + ii); ii++; } } How many times is 2 printed as a part of the output? A. Zero B.Once C.Twice D.Thrice E. Compilation fails. QUESTION: 11 Given: import java.io.IOException; public class Y { public static void main(String[] args) { try { doSomething(); } catch (RuntimeException e) { System.out.println(e); } } static void doSomething() { if (Math.random() > 0.5) throw new IOException(); throw new RuntimeException(); } } Which two actions, used independently, will permit this class to compile? A. Adding throws IOException to the main() method signature B. Adding throws IOException to the doSoomething() method signature C. Adding throws IOException to the main() method signature and to the dosomething() method D. Adding throws IOException to the dosomething() method signature and changing the catch argument to IOException E. Adding throws IOException to the main() method signature and changing the catch argument to IOException QUESTION: 12 Given: class X { String str = "default"; X(String s) { str = s;} void print () { System.out.println(str); } public static void main(String[] args) { new X("hello").print(); } } What is the result? A. hello B. default C. Compilation fails D. The program prints nothing E. An exception is thrown at run time QUESTION: 13 Given: public class SampleClass { public static void main(String[] args) { AnotherSampleClass asc = new AnotherSampleClass(); SampleClass sc = new SampleClass(); // TODO code application logic here } } class AnotherSampleClass extends SampleClass { } Which statement, when inserted into line "// TODO code application logic here ", is valid change A. asc = sc; B. sc = asc; C. asc = (object) sc; D. asc = sc.clone () QUESTION: 14 Given the code fragment: System.out.println("Result: " + 2 + 3 + 5); System.out.println("Result: " + 2 + 3 * 5); What is the result? A. Result: 10 Result: 30 B. Result: 10 Result: 25 C. Result: 235 Result: 215 D. Result: 215 Result: 215 E. Compilation fails QUESTION: 15 Which code fragment is illegal? A. class Base1 { abstract class Abs1 { }} B. abstract class Abs1 { void doit () { }} C. class Basel {abstract class Abs1 extends Basel} D. abstract int var1 = 89; QUESTION: 16 Given the code fragment: int a = 0; a++; System.out.println(a++); System.out.println(a); What is the result? A.1 2 B.0 1 C.1 1 D.2 2 QUESTION: 17 Given: public class x{ public static void main (string [] args){ String theString = "Hello World"; System.out.println(theString.charAt(11)); } } What is the result? A. There is no output B. d is output C. A StringIndexOutOfBoundsException is thrown at runtime D. An ArrayIndexOutOfBoundsException is thrown at runtime E. A NullPointException is thrown at runtime F. A StringArrayIndexOutOfBoundsException is thrown at runtime QUESTION: 18 Given a java source file: class x { x () {} private void one () {} } public class Y extends x { Y () {} private void two () {one();} public static void main (string [] args) { new Y().two (); } } What changes will make this code compile? A. adding the public modifier to the declaration of class x B. adding the protected modifier to the x() constructor C. changing the private modifier on the declaration of the one() method to protected D. removing the Y () constructor E. removing the private modifier from the two () method QUESTION: 19 Given: #1 package handy.dandy; public class KeyStroke { public void typeExclamation() { System.out.println("!") } } #2 package handy; /* Line 1 */ public class Greet { /* Line 2 */ public static void main(String[] args) { /* Line 3 */ String greeting = "Hello"; /* Line 4 */ System.out.print(greeting); /* Line 5 */ Keystroke stroke = new Keystroke; /* Line 6 */ stroke.typeExclamation(); /* Line 7 */ } /* Line 8 */ } /* Line 9 */ What three modifications, made independently, made to class greet, enable the code to compile and run? A. Line 6 replaced with handy.dandy.keystroke stroke = new KeyStroke ( ); B. Line 6 replaced with handy.*.KeyStroke = new KeyStroke ( ); C. Line 6 replaced with handy.dandy.KeyStroke Stroke = new handy.dandy.KeyStroke(); D. import handy.*; added before line 1 E. import handy.dandy.*; added after line 1 F. import handy.dandy,KeyStroke; added after line 1 G. import handy.dandy.KeyStroke.typeException(); added before line 1 QUESTION: 20 Given: String message1 = "Wham bam!"; String message2 = new String("Wham bam!"); if (message1 == message2) System.out.println("They match"); if (message1.equals(message2)) System.out.println("They really match"); What is the result? A. They match They really match B. They really match C. They match D. Nothing Prints E. They really match They really match QUESTION: 21 Given: public class Speak { /* Line 1 */ public static void main(String[] args) { /* Line 2 */ Speak speakIT = new Tell(); /* Line 3 */ Tell tellIt = new Tell(); /* Line 4 */ speakIT.tellItLikeItIs(); /* Line 5 */ (Truth)speakIt.tellItLikeItIs(); /* Line 6 */ ((Truth)speakIt).tellItLikeItIs(); /* Line 7 */ tellIt.tellItLikeItIs(); /* Line 8 */ (Truth)tellIt.tellItLikeItIs(); /* Line 9 */ ((Truth)tellIt).tellItLikeItIs(); /* Line 10 */ } } class Tell extends Speak implements Truth { public void tellItLikeItIs() { System.out.println("Right on!"); } } interface Truth { public void tellItLikeItIs()}; Which three lines will compile and output “right on!”? A. Line 5 B. Line 6 C. Line 7 D. Line 8 E. Line 9 F. Line 10 QUESTION: 22 Given the code fragment: String h1 = "Bob"; String h2 = new String ("Bob"); What is the best way to test that the values of h1 and h2 are the same? A. if (h1 == h2) B. if (h1.equals(h2)) C. if (h1 = = h2) D. if (h1.same(h2)) QUESTION: 23 Which two are valid declarations of a two-dimensional array? A. int[][] array2D; B. int[2][2] array2D; C. int array2D[]; D. int[] array2D[]; E. int[][] array2D[]; QUESTION: 24 Given the code fragment: System.out.println ("Result:" +3+5); System.out.println ("result:" + (3+5)); What is the result? A. Result: 8 Result: 8 B. Result: 35 Result: 8 C. Result: 8 Result: 35 D. Result: 35 Result: 35 QUESTION: 25 Given: public class Main { public static void main(String[] args) throws Exception { doSomething(); } private static void doSomething() throws Exception { System.out.println("Before if clause"); if (Math.random() > 0.5) { throw new Exception(); } System.out.println ("After if clause"); } } Which two are possible outputs? (dono y) A. Before if clause Exception in thread “main” java.lang.Exception At Main.doSomething (Main.java:8) At Main.main (Main.java:3) B. Before if clause Exception in thread “main” java.lang.Exception At Main.doSomething (Main.java:8) At Main.main (Main.java:3) After if clause' C. Exception in thread “main” java.lang.Exception At Main.doSomething (Main.java:8) At Main.main (Main.java:3) D. Before if clause After if clause QUESTION: 26 A method doSomething () that has no exception handling code is modified to trail a method that throws a checked exception. Which two modifications, made independently, will allow the program to compile? A. Catch the exception in the method doSomething(). B. Declare the exception to be thrown in the doSomething() method signature. C. Cast the exception to a RunTimeException in the doSomething() method. D. Catch the exception in the method that calls doSomething(). QUESTION: 27 Given the code fragment: String color = "Red"; switch(color) { case "Red": System.out.println("Found Red"); case "Blue": System.out.println("Found Blue"); break; case "White": System.out.println("Found White"); break; default: System.out.println("Found Default"); } What is the result? A. Found Red B. Found Red Found Blue C. Found Red Found Blue Found White D. Found Red Found Blue Found White Found Default QUESTION: 28 Which two may precede the word "class" in a class declaration? A. local B. public C. static D. volatile E. synchronized QUESTION: 29 Which three are bad practices? A. Checking for ArrayindexoutofBoundsException when iterating through an array to determine when all elements have been visited B. Checking for Error and. If necessary, restarting the program to ensure that users are unaware problems C. Checking for FileNotFoundException to inform a user that a filename entered is not valid D. Checking for ArrayIndexoutofBoundsExcepcion and ensuring that the program can recover if one occur E. Checking for an IOException and ensuring that the program can recover if one Occurs QUESTION: 30 Given: public class Bark { // Insert code here - Line 5 public abstract void bark(); // Line 6 } // Line 7 // Line 8 // Insert code here - Line 9 public void bark() { System.out.println("woof"); } } What code should be inserted? A. 5. class Dog { 9. public class Poodle extends Dog} B. 5. abstract Dog { 9. public class poodle extends Dog} C. 5. abstract class Dog { 9. public class Poodle extends Dog} D. 5. abstract Dog { 9. public class Poodle implements Dog} E. 5. abstract Dog { 9. public class Poodle implements Dog { F. 5. abstract class Dog { 9. public class Poodle implements Dog { QUESTION: 31 Given: class X {} class Y {Y () {}} class Z {z(int i ) {} } Which class has a default constructor? A. X only B. Y only C. Z only D. X and Y E. Y and Z F. X and Z G. X, Y and Z QUESTION: 32 Given: Public static void main (String [] args) { int a, b, c = 0; int a, b, c; int g, int h, int i, = 0; int d, e, F; int k, l, m; = 0; Which two declarations will compile? A. int a, b, c = 0; B. int a, b, c; C. int g, int h, int i = 0; D. int d, e, F; E. int k, l, m = 0; QUESTION: 33 Given the code fragment: int j=0, k =0; for (int i=0; i < x; i++) { do { k=0; while (k < z) { k++; System.out.print(k + " "); } System.out.println(" "); j++; } while (j< y); System.out.println("----"); } What values of x, y, z will produce the following result? 1 2 3 4 1 2 3 4 1 2 3 4 ------ 1 2 3 4 ------ A. X = 4, Y = 3, Z = 2 B. X = 3, Y = 2, Z = 3 C. X = 2, Y = 3, Z = 3 D. X = 4, Y = 2, Z = 3 E. X = 2, Y = 3, Z = 4 QUESTION: 34 Which statement initializes a stringBuilder to a capacity of 128? A. StringBuilder sb = new String("128"); B. StringBuilder sb = StringBuilder.setCapacity(128); C. StringBuilder sb = StringBuilder.getInstance(128); D. StringBuilder sb = new StringBuilder(128); QUESTION: 35 Given: public class DoCompare4 { public static void main(String[] args) { String[] table = {"aa", "bb", "cc"}; int ii =0; do while (ii < table.length) System.out.println(ii++); while (ii < table.length); } } What is the result? A. 0 B. 0 1 2 C. 0 1 2 0 1 2 0 1 2 D. Compilation fails QUESTION: 36 A method is declared to take three arguments. A program calls this method and passes only two arguments. What is the result? A. Compilation fails. B. The third argument is given the value null. C. The third argument is given the value void. D. The third argument is given the value zero. E. The third argument is given the appropriate false value for its declared type. F. An exception occurs when the method attempts to access the third argument. QUESTION: 37 Given the fragment: //(src, srcpos, dest, destpos) int [] array = {1, 2, 3, 4, 5}; System.arraycopy (array, 2, array, 1, 2); System.out.print (array [1]); System.out.print (array[4]); What is the result? A. 14 B. 15 C. 24 D. 25 E. 34 F. 35 QUESTION: 38 Given the following code fragment: if (value >= 0) { if (value != 0) System.out.print("the "); else System.out.print("quick "); if (value < 10) System.out.print("brown "); if (value > 30) System.out.print("fox "); else if (value < 50) System.out.print("jumps "); else if (value < 10) System.out.print("over "); else System.out.print("the "); if (value > 10) System.out.print("lazy "); } else { System.out.print("dog"); } System.out.print("… "); } What is the result if the integer value is 33? A. The fox jump lazy … B. The fox lazy … C. Quick fox over laz D. Quick fox the …. QUESTION: 39 Which three are advantages of the Java exception mechanism? A. Improves the program structure because the error handling code is separated from the normal program function B. Provides a set of standard exceptions that covers all the possible errors C. Improves the program structure because the programmer can choose where to handle exceptions D. Improves the program structure because exceptions must be handled in the method in which they occurred E. allows the creation of new exceptions that are tailored to the particular program Being QUESTION: 40 Given: public class MyFor3 { public static void main(String [] args) { int [] xx = null; System.out.println(xx); } } What is the result? A. null B. compilation fails C. Java.lang.NullPointerException D. 0 QUESTION: 41 Given: public class Main { public static void main (String[] args) { doSomething(); } private static void doSomething() { doSomeThingElse(); } private static void doSomeThingElse() { throw new Exception(); } } Which approach ensures that the class can be compiled and run? A. Put the throw new Exception() statement in the try block of try – catch B. Put the doSomethingElse() method in the try block of a try – catch C. Put the doSomething() method in the try block of a try – catch D. Put the doSomething() method and the doSomethingElse() method in the try block of a try – catch QUESTION: 42 Given: public class ScopeTest1 { public static void main(String[] args) { doStuff(); int x1 = x2; // line x1 int x2 = j; // line x2 // line x3 } static void doStuff() { System.out.println(j); // line x4 } static int j; } Which line causes a compilation error? A. line x1 B. line x2 C. line x3 D. line x4 (Ans: x2 cannot be resolved to variable) QUESTION: 43 Given: class Overloading { void x(int i) { System.out.println("one"); } void x (String s) { System.out.println("two"); } void x (double d) { System.out.println("three"); } public static void main(String[] args) { new Overloading().x (4.0); } } What is the result? A. One B. Two C.Three D. Compilation fails QUESTION: 44 Which declaration initializes a boolean variable? A. boolean h = 1; B. boolean k = 0; C. boolean m = null; D. boolean j = (1 < 5); QUESTION: 45 Given: public class Basic { private static int letter; public static int getLetter(); public static void Main(String[] args) { System.out.println(getLetter()); } } Why will the code not compile? A. A static field cannot be private. B. The getLetter method has no body. C. There is no setletter method. D. The letter field is uninitialized. E. It contains a method named Main instead of ma QUESTION: 46 Given: public class Circle { double radius; public double area: public Circle (double r) { radius = r;} public double getRadius() {return radius;} public void setRadius(double r) {radius = r;} public double getArea() { return /* ??? */;} } class App { public static void main(String[] args) { Circle c1 = new Circle(17.4); c1.area = Math.PI * c1.getRadius() * c1.getRadius(); } } This class is poorly encapsulated. You need to change the circle class to compute and return the area instead. What three modifications are necessary to ensure that the class is being properly encapsulated? A. Change the access modifier of the setradius () method to private B. Change the getArea () method public double getArea () { return area; } C. When the radius is set in the Circle constructor and the setRadius () method, recomputed the area and store it into the area field D. Change the getRadius () method: public double getRadius () { area = Math.PI * radius * radius; return radius; } QUESTION: 47 Given a code fragment: StringBuilder sb = new StringBuilder (); String h1 = "HelloWorld"; sb.append("Hello").append ("world"); if (h1 == sb.toString()) { System.out.println("They match"); } if (h1.equals(sb.toString())) { System.out.println("They really match"); } What is the result? A. They match They really match B. They really match C. They match D. Nothing is printed to the screen QUESTION: 48 Given the following code: public class Simple { /* Line 1 */ public float price; /* Line 2 */ public static void main (String[] args) { /* Line 3 */ Simple price = new Simple (); /* Line 4 */ price = 4; /* Line 5 */ } /* Line 6 */ } /* Line 7 */ What will make this code compile and run? A. Change line 2 to the following: Public int price B. Change line 4 to the following: int price = new simple (); C. Change line 4 to the following: Float price = new simple (); D. Change line 5 to the following: Price = 4f; E. Change line 5 to the following: price.price = 4; F. Change line 5 to the following: Price = (float) 4: G. Change line 5 to the following: Price = (Simple) 4; (gues) H. The code compiles and runs properly; no changes are necessary QUESTION: 49 Given: public class DoWhile { public static void main (String [] args) { int ii = 2; do { System.out.println (ii); } while (--ii); } } What is the result? A. 2 1 B. 2 1 0 C. null D. an infinite loop E. compilation fails QUESTION: 50 You are writing a method that is declared not to return a value. Which two are permitted in the method body? A. omission of the return statement B. return null; C. return void; D. return; QUESTION: 51. Identify two benefits of using ArrayList over array in software development. A. reduces memory footprint B. implements the Collection API C. is multi.thread safe D. dynamically resizes based on the number of elements in the list QUESTION: 52. Which three are valid types for switch? A. int B. float C. double D. integer E. String F. Float QUESTION: 53. Give: public class MyFive { static void main(String[] args) { short ii; short jj = 0; for (ii = kk;ii > 6; ii -= 1) { // line x // jj++; } System.out.println("jj = " + jj); } } What value should replace KK in line x to cause jj = 5 to be output? A. -1 B. 1 C. 5 D. 8 E. 11 QUESTION: 54. Given the code fragment: Boolean b1 = true; Boolean b2 = false; int 1 = 0; while (foo) {} Which one is valid as a replacement for foo? A. b1.compareTo(b2) B. i = 1 C. i == 2? -1:0 D. "foo".equals("bar") QUESTION: 55. Given: public class SuperTest { public static void main(String[] args) { statement1 statement2 statement3 } } class Shape { public Shape() { System.out.println("Shape:constructor"); } public void foo() { System.out.println("Shape: foo"); } } class Square extends Shape { public Square() { super(); } public Square(String label) { System.out.println("Square:constructor"); } public void foo() { super.foo(); } public void foo(String label) { System.out.println("Square:foo"); } } What should statement1, statement2, and statement3, be respectively, in order to produce the result? Shape: constructor Square: foo Shape: foo A. Square square = new Square ("bar"); square.foo ("bar"); square.foo(); B. Square square = new Square ("bar"); square.foo ("bar"); square.foo ("bar"); C. Square square = new Square (); square.foo (); square.foo(bar); D. Square square = new Square (); square.foo (); square.foo("bar"); E. Square square = new Square (); square.foo (); square.foo (); QUESTION: 56. Give: Public Class Test { } Which two packages are automatically imported into the java source file by the java compiler? A. Java.lang B. Java.awt C. Javax.net D. Java.* E. The package with no name QUESTION: 57. Given: public class X implements Z { public String toString() { return "I am X"; } public static void main(String[] args) { Y myY = new Y(); X myX = myY; Z myZ = myX; System.out.println(myZ); } } class Y extends X { public String toString() { return "I am Y"; } } interface Z {} What is the reference type of myZ and what is the type of the object it references? A. Reference type is Z; object type is Z. B. Reference type is Y; object type is Y. C. Reference type is Z; object type is Y. D. Reference type is X; object type is Z. QUESTION: 58. Given: What is the result? A. sc: class.Object asc: class.AnotherSampleClass B. sc: class.SampleClass asc: class.AnotherSampleClass C. sc: class.AnotherSampleClass asc: class.SampleClass D. sc: class.AnotherSampleClass asc: class.AnotherSampleClass QUESTION: 59. Given the code fragment: public static void main(String[] args) { String [] table = {"aa", "bb", "cc"}; int ii = 0; for (String ss:table) { while (ii < table.length) { System.out.println (ii); ii++; break; } } } How many times is 2 printed? A. zero B. once C. twice D. thrice E. it is not printed because compilation fails QUESTION: 60. Given: public class SampleClass { public static void main(String[] args) { SampleClass sc, scA, scB; sc = new SampleClass(); scA = new SampleClassA(); scB = new SampleClassB(); System.out.println("Hash is : " + sc.getHash() + ", " + scA.getHash() + ", " + scB.getHash()); } public int getHash() { return 111111; } } class SampleClassA extends SampleClass { public long getHash() { return 44444444; } } class SampleClassB extends SampleClass { public long getHash() { return 999999999; } } What is the result? A. Compilation fails B. An exception is thrown at runtime C. There is no result because this is not correct way to determine the hash code D. Hash is: 111111, 44444444, 999999999 QUESTION: 61. Which two will compile, and can be run successfully using the command: Java fred hello walls A. class Fred1{ public static void main (String args) { System.out.println(args[1]); } } B. class Fred1{ public static void main (String [] args) { System.out.println(args[2]); } } C. class Fred1 { public static void main (String [] args) { System.out.println (args); } } D. class Fred1 { public static void main (String [] args) { System.out.println (args [1]); } } QUESTION: 62. Given: public abstract class Wow { private int wow; public wow (int wow) { this.wow = wow; } public void wow () {} private void wowza () {} } What is true about the class Wow? A. It compiles without error. B. It does not compile because an abstract class cannot have private methods. C. It does not compile because an abstract class cannot have instance variables. D. It does not compile because an abstract class must have at least one abstract method. E. It does not compile because an abstract class must have a constructor with no arguments. QUESTION: 63. Given: class X { static void m(int i) { } public static void main (String [] args) { int j = 12; m (j); System.out.println(j); } } What is the result? A. 7 B. 12 C. 19 D. Compilation fails E. An exception is thrown at run time QUESTION: 64. Which two statements are true? A. An abstract class can implement an interface. B. An abstract class can be extended by an interface. C. An interface CANNOT be extended by another interface. D. An interface can be extended by an abstract class. E. An abstract class can be extended by a concrete class. F. An abstract class CANNOT be extended by an abstract class. QUESTION: 65. Given: class Overloading { int x(double d) { System.out.println("one" ); return 0; } String x(double d) { System.out.println("two" ); return null; } double x(double d) { System.out.println("three" ); return 0.0; } public static void main(String[] args) { new Overloading().x(4.0) } } What is the result? A. One B. Two C. Three D. Compilation fails QUESTION: 66. The catch clause argument is always of type . A. Exception B. Exception but NOT including RuntimeException C. Throwable D. RuntimeException E. CheckedException F. Error QUESTION: 67. Given the code fragment: 1. ArrayList<Integer> list = new ArrayList<>(1); 2. list.add(1001); 3. list.add(1002); 4. System.out.println(list.get(list.size())); What is the result? A. Compilation fails due to an error on line 1. B. An exception is thrown at run time due to error on line 3 C. C. An exception is thrown at run time due to error on line 4 D. 1002 QUESTION: 68. View the Exhibit. public class Hat { public int ID =0; public String name = "hat"; public String size = "One Size Fit All"; public String color=""; public String getName() { return name; } public void setName(String name) { this.name = name; } } Given public class TestHat { public static void main(String[] args) { Hat blackCowboyHat = new Hat(); } } Which statement sets the name of the Hat instance? A. blackCowboyHat.setName = "Cowboy Hat"; B. setName("Cowboy Hat"); C. Hat.setName("Cowboy Hat"); D. blackCowboyHat.setName("Cowboy Hat"); QUESTION: 69. public class Two { public static void main(String[] args) { try { doStuff(); system.out.println("1"); } catch { system.out.println("2"); }} public static void do Stuff() { if (Math.random() > 0.5) throw new RunTimeException(); doMoreStuff(); System.out.println("3 "); } public static void doMoreStuff() { System.out.println("4"); } } Which two are possible outputs? A. 2 B. 4 C. 1 D. 1 QUESTION: 70. Given: public class MyFor { public static void main(String[] args) { for (int ii = 0; ii < 4; ii++) { System.out.println("ii = "+ ii); ii = ii +1; } } } What is the result? A. ii = 0 ii = 2 B. ii = 0 ii = 1 ii = 2 ii = 3 C. ii = D. Compilation fails QUESTION: 71 Given the code fragment: int [][] array2d = new int[2][3]; System.out.println("Loading the data."); for ( int x = 0; x < array2d.length; x++) { for ( int y = 0; y < array2d[0].length; y++) { System.out.println(" x = " + x); System.out.println(" y = " + y); // insert load statement here. } } System.out.println("Modify the data. "); for ( int x = 0; x < array2d.length; x++) { for ( int y = 0; y < array2d[0].length; y++) { System.out.println(" x = " + x); System.out.println(" y = " + y); // insert modify statement here. } } Which pair of load and modify statement should be inserted in the code? The load statement should set the array's x row and y column value to the sum of x and y The modify statement should modify the array's x row and y column value by multiplying it by 2 A. Load statement: array2d(x,y) = x + y; Modify statement: array2d(x,y) = array2d(x,y) * 2 B. Load statement: array2d[x y] = x + y; Modify statement: array2d[x y] = array2d[x y] * 2 C. Load statement: array2d[x,y] = x + y; Modify statement: array2d[x,y] = array2d[x,y] * 2 D. Load statement: array2d[x][y] = x + y; Modify statement: array2d[x][y] = array2d[x][y] * 2 E. Load statement: array2d[[x][y]] = x + y; Modify statement: array2d[[x][y]] = array2d[[x][y]] * 2. QUESTION: 72. Given: public class DoBreak1 { public static void main(String[] args) { String[] table = {"aa", "bb", "cc", "dd"}; for (String ss: table) { if ( "bb".equals(ss)) { continue; } System.out.println(ss); if ( "cc".equals(ss)) { break; }}}} What is the result? A. aa cc B. aa bb cc C. cc dd D. cc E. Compilation fails. QUESTION: 73. 1. class StaticMethods { 2. static void one() { 3. two(); 4. StaticMethods.two(); 5. three(); 6. StaticMethods.four(); 7. } 8. static void two() { } 9. void three() { 10. one(); 11. StaticMethods.two(); 12. four(); 13. StaticMethods.four(); 14. } 15. void four() { } 16. } Which three lines are illegal? A. line 3 B. line 4 C. line 5 D. line 6 E. line 10 F. line 11 G. line 12 H. line 13 QUESTION: 74 Which is a valid abstract class? A. public abstract class Car { protected void accelerate(); } B. public interface Car { protected abstract void accelerate(); } C. public abstract class Car { protected final void accelerate(); } D. public abstract class Car { protected abstract void accelerate(); } E. public abstract class Car { protected abstract void accelerate() { //more car can do }} QUESTION: 75 View the exhibit: public class Student { public String name = ""; public int age = 0; public String major = "Undeclared"; public boolean fulltime = true; public void display() { System.out.println("Name: " + name + " Major: " + major); } public boolean isFullTime() { return fulltime; } } Given: Public class TestStudent { public static void main(String[] args) { Student bob = new Student (); bob.name = "Bob"; bob.age = 18; bob.year = 1982; } } What is the result? A. year is set to 1982. B. bob.year is set to 1982 C. A runtime error is generated. D. A compile time error is generated. QUESTION: 76 Given the code fragment: String name = "Spot"; int age = 4; String str ="My dog " + name + " is " + age; System.out.println(str); And StringBuilder sb = new StringBuilder(); Using StringBuilder, which code fragment is the best potion to build and print the following string My dog Spot is 4 A. sb.append("My dog " + name + " is " + age); System.out.println(sb); B. sb.insert("My dog ").append( name + " is " + age); System.out.println(sb); C. sb.insert("My dog ").insert( name ).insert(" is " ).insert(age); System.out.println(sb); D. sb.append("My dog ").append( name ).append(" is " ).append(age); System.out.println(sb); QUESTION: 77 Given: public class Main { public static void main(String[] args) { try { doSomething(); } catch (SpecialException e) { System.out.println(e); }} static void doSomething() { int [] ages = new int[4]; ages[4] = 17; doSomethingElse(); } static void doSomethingElse() { throw new SpecialException("Thrown at end of doSomething() method"); } } What is the output? A. SpecialException: Thrown at end of doSomething() method B. Error in thread "main" java.lang. ArrayIndexOutOfBoundseror C. Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 4 at Main.doSomething(Main.java:12) at Main.main(Main.java:4) D. SpecialException: Thrown at end of doSomething() method at Main.doSomethingElse(Main.java:16) at Main.doSomething(Main.java:13) at Main.main(Main.java:4) QUESTION: 78 View the exhibit: public class Student { public String name = ""; public int age = 0; public String major = "Undeclared"; public boolean fulltime = true; public void display() { System.out.println("Name: " + name + " Major: " + major); } public boolean isFullTime() { return fulltime; } } Which line of code initializes a student instance? A. Student student1; B. Student student1 = Student.new(); C. Student student1 = new Student(); D. Student student1 = Student(); QUESTION: 79 int [] array = {1,2,3,4,5}; for (int i: array) { if ( i < 2) { keyword1 ; } System.out.println(i); if ( i == 3) { keyword2 ; }} What should keyword1 and keyword2 be respectively, in oreder to produce output 2345? A. continue, break B. break, break C. break, continue D. continue, continue QUESTION: 80 int i, j=0; i = (3* 2 +4 +5 ) ; j = (3 * ((2+4) + 5)); System.out.println("i:"+ i + "\nj":+j); What is the result? A. i: 16 B. 33 C. i: 15 D. 33 E. i: 33 F. 23 G. i: 15 H. 23 QUESTION: 81 boolean log3 = ( 5.0 != 6.0) && ( 4 != 5); boolean log4 = (4 != 4) || (4 == 4); System.out.println("log3:"+ log3 + \nlog4" + log4); What is the result? A. log3:false log4:true B. log3:true log4:true C. log3:true log4:false D. log3:false log4:false QUESTION: 82 Which statement will emoty the contents of a StringBuilder variable named sb? A. sb.deleteAll(); B. sb.delete(0, sb.size()); C. sb.delete(0, sb.length()); D. sb.removeAll(); QUESTION: 83 Class StaticField { static int i = 7; public static void main(String[] args) { StaticFied obj = new StaticField(); obj.i++; StaticField.i++; obj.i++; System.out.println(StaticField.i + " "+ obj.i); } } What is the result? A. 10 10 B. 8 9 C. 9 8 D. 7 10 QUESTION: 84 Which two are valid array declaration? A. Object array[]; B. Boolean array[3]; C. int[] array; D. Float[2] array; QUESTION: 85 Given: class Overloading { int x(double d) { System.out.println("one"); return 0; } String x(double d) { System.out.println("two"); return null; } double x(double d) { System.out.println("three"); return 0.0; } public static void main(String[] args) { new Overloading().x(4.0); } } What is the result? A. one B. two C. three D. Compilation fails. QUESTION: 86 Given: public class MainMethod { void main() { System.out.println("one"); } static void main(String args) { System.out.println("two"); } public static void main(String[] args) { System.out.println("three"); } void mina(Object[] args) { System.out.println("four"); } } What is printed out when the program is excuted? A. one B. two C. three D. four QUESTION: 87 Given: public class ScopeTest { int j, int k; public static void main(String[] args) { ew ScopeTest().doStuff(); } void doStuff() { nt x = 5; oStuff2(); System.out.println("x"); } void doStuff2() { nt y = 7; ystem.out.println("y"); or (int z = 0; z < 5; z++) { ystem.out.println("z"); ystem.out.println("y"); } Which two items are fields? A. j B. k C. x D. y E. z QUESTION: 88 A method is declared to take three arguments. A program calls this method and passes only two arguments. What is the results? A. Compilation fails. B. The third argument is given the value null. C. The third argument is given the value void. D. The third argument is given the value zero. E. The third argument is given the appropriate falsy value for its declared type. F. An exception occurs when the method attempts to access the third argument. QUESTION: 89 public class ForTest { public static void main(String[] args) { int[] arrar = {1,2,3}; for ( foo ) { } } } Which three are valid replacements for foo so that the program will compiled and run? A. int i: array B. int i = 0; i < 1; i++ C. ;; D. ; i < 1; i++ E. ; i < 1; QUESTION: 90 Given: public class SampleClass { public static void main(String[] args) { AnotherSampleClass asc = new AnotherSampleClass(); SampleClass sc = new SampleClass(); sc = asc; System.out.println("sc: " + sc.getClass()); System.out.println("asc: " + asc.getClass()); }} class AnotherSampleClass extends SampleClass { } What is the result? A. sc: class Object asc: class AnotherSampleClass B. sc: class SampleClass asc: class AnotherSampleClass C. sc: class AnotherSampleClass asc: class SampleClass D. sc: class AnotherSampleClass asc: class AnotherSampleClass QUESTION: 91 Given the code fragment: int b = 3; if ( !(b > 3)) { System.out.println("square "); }{ System.out.println("circle "); } System.out.println("..."); What is the result? A. square... B. circle... C. squarecircle... D. Compilation fails. QUESTION: 92 What is the proper way to defined a method that take two int values and returns their sum as an int value? A. int sum(int first, int second) { first + second; } B. int sum(int first, second) { return first + second; } C. sum(int first, int second) { return first + second; } D. int sum(int first, int second) { return first + second; } E. void sum (int first, int second) { return first + second; } QUESTION: 93 Which two are Java Exception classes? A. SercurityException B. DuplicatePathException C. IllegalArgumentException D. TooManyArgumentsException QUESTION: 94 Given the for loop construct: for ( expr1 ; expr2 ; expr3 ) { statement; } Which two statements are true? A. This is not the only valid for loop construct; there exits another form of for loop constructor. B. The expression expr1 is optional. it initializes the loop and is evaluated once, as the loop begin. C. When expr2 evaluates to false, the loop terminates. It is evaluated only after each iteration through the loop. D. The expression expr3 must be present. It is evaluated after each iteration through the loop. QUESTION: 95 public class StringReplace { public static void main(String[] args) { String message = "Hi everyone!"; System.out.println("message = " + message.replace("e", "X")); }} What is the result? A. message = Hi everyone! B. message = Hi XvXryonX! C. A compile time error is produced. D. A runtime error is produced. E. message = F. message = Hi Xveryone! QUESTION: 96 Which two statements are true for a two-dimensional array? A. It is implemented as an array of the specified element type. B. Using a row by column convention, each row of a two-dimensional array must be of the same size C. At declaration time, the number of elements of the array in each dimension must be specified D. All methods of the class Object may be invoked on the two-dimensional array. QUESTION: 97 Which three statements are benefits of encapsulation? A. allows a class implementation to change without changing the clients B. protects confidential data from leaking out of the objects C. prevents code from causing exceptions D. enables the class implementation to protect its invariants E. permits classes to be combined into the same package F. enables multiple instances of the same class to be created safely