Java Standard Test 14 Code 819

Question: NOTE: Although Class.isArray() and Object.clone() methods are not officially on the exam, you may still see a question or two in the exam that requires you to know about these methods.

Given the following declaration:

int[][] twoD = { { 1, 2, 3} , { 4, 5, 6, 7}, { 8, 9, 10 } };

What will the following lines of code print?

System.out.print(twoD[1].length);
System.out.print(twoD[2].getClass().isArray());
System.out.print(twoD[1][2]);
System.out.print(twoD[0] == twoD.clone()[0]);

Select 1 option(s)

Question: Which of the following statements are correct regarding synchronization and locks?

Select 2 option(s)

Question: What will be printed by the following code if it is run with command line: java TestClass -0.50 ?

public class TestClass{
public static double getSwitch(String str){
return Double.parseDouble(str.substring(1, str.length()-1) );
}
public static void main(String args []){
switch(getSwitch(args[0])){
case 0.0 : System.out.println("Hello");
case 1.0 : System.out.println("World"); break;
default : System.out.println("Good Bye");
}
}
}

Select 1 option(s)

Question: Given the following method code:

public void myMethod() throws MyException {

//method code

}

Select 1 option(s)

Question: Which of the following are valid implementations of java.util.Comparator?

Select 3 option(s)

Question: Which statements regarding the following code are correct?

class Outer
{
private void Outer() { }
protected class Inner
{
}
}

Select 1 option(s)

Question: What will be the output of the following program?

class Test
{
static int i1, i2, i3;
public static void main(String[] args)
{
try
{
test(i1 = 1, oops(i2=2), i3 = 3);
} catch (Exception e)
{
System.out.println(i1+" "+i2+" "+i3);
}
}
static int oops(int i) throws Exception
{
throw new Exception("oops");
}
static int test(int a, int b, int c) {
return a + b + c;
}
}

Select 1 option(s)

Question: Given:

class Course{
private String id;
private String name;

public Course(String id, String name){
this.id = id; this.name = name;
}
//accessors not shows
}

What will the following code print?

List cList = Arrays.asList(
new Course("803", "OCAJP 7"),
new Course("808", "OCAJP 8"),
new Course("809", "OCPJP 8")
);

cList.stream().filter(c->c.getName().indexOf("8")>-1)
.map(c->c.getId())
.collect(Collectors.joining("1Z0-"));
cList.stream().forEach(c->System.out.println(c.getId()));

Select 1 option(s)

Question: What will the following code print when compiled and run?

List ls = Arrays.asList(1, 2, 3);
ls.stream().forEach(System.out::print)
.map(a->a*2)
.forEach(System.out::print);

Select 1 option(s)

Question: Which of the following statements are true?

Select 2 option(s)

Question: What will be printed when the following code is compiled and run?

public class LoadTest{

public static void main(String[] args) throws Exception {
LoadTest t = new LoadTest();
int i = t.getLoad();
double d = t.getLoad();
System.out.println( i + d );
}

public int getLoad() {
return 1;
}

public double getLoad(){
return 3.0;
}

}

Select 1 option(s)

Question: Given the following code:

class M { }
class N{
private M m = new M();
public void makeItNull(M pM){
pM = null;
}
public void makeThisNull(){
makeItNull(m);
}
public static void main(String[] args){
N n = new N();
n.makeThisNull();
}
}

Which of the following statements are correct?

Select 1 option(s)

Question: Given:

public class Switcher{

public static void main(String[] args){
switch(Integer.parseInt(args[1])) //1
{
case 0 :
var b = false; //2
break;

case 1 :
b = true; // 3
break;
}

if(b) System.out.println(args[2]); //4
}
}

What will the above program print if compiled and run using the following command line:
java Switcher 1 2 3

Select 1 option(s)

Question: What would be the result of attempting to compile and run the following program?

class TestClass{
static TestClass ref;
String[] arguments;
public static void main(String args[]){
ref = new TestClass();
ref.func(args);
}
public void func(String[] args){
ref.arguments = args;
}
}

Select 1 option(s)

Question: Given that classes B1 and B2 extend class A and classes C1, C2 are subclasses of B1.

Further, assume that method public void m1(){ ... } is defined in all of these classes EXCEPT B1 and C1.


class A{
public void m1(){ }
}

class B1 extends A{
}
class B2 extends A{
public void m1(){ }
}

class C1 extends B1{
}
class C2 extends B1{
public void m1(){ }
}


Assume that "objectOfXX" means a variable that points to an object of class XX. So, objectOfC1 means a reference variable that is pointing to an object of class C1.

Which of the following statements are correct?

Select 1 option(s)

Question: What will the following code print when compiled and run?

List iList = Arrays.asList(1, 2, 3, 4, 5, 6, 7);
Predicate p = x->x%2==0;
List newList = iList.stream().filter(p).filter(x->x>3).collect(Collectors.toList());
System.out.println(newList);

Select 1 option(s)

Question: Identify correct statement about the following code -

class X{
int val = 10;
}

class Y extends X{
Y val = null; //1
}

public class TestClass extends X{

public static void main(String[] args){
Y y = new Y();
int k = (X) y.val ; //2
System.out.println(k);

}
}

Select 1 option(s)

Question: What can be inserted in the following code at //1 so that it will print the number of lines present in the given file?

public void countLines(String filePath) throws Exception{
//1
System.out.println(ref.count());
}

Select 1 option(s)

Question: Given the following declarations, identify which statements will return true:

Integer i1 = 1;
Integer i2 = new Integer(1);
int i3 = 1;
Byte b1 = 1;
Long g1 = 1L;
Double d = 1.0;

Select 2 option(s)

Question: What will the following program print?

public class TestClass{
public static void main(String[] args){
int x = 1;
int y = 0;
if( x/y ) System.out.println("Good");
else System.out.println("Bad");
}
}

Select 1 option(s)

Question: What will the following code print when compiled and run?

class Base{
void methodA(){
System.out.println("base - MethodA");
}
}

class Sub extends Base{
public void methodA(){
System.out.println("sub - MethodA");
}
public void methodB(){
System.out.println("sub - MethodB");
}
public static void main(String args[]){
Base b=new Sub(); //1
b.methodA(); //2
b.methodB(); //3
}
}

Select 1 option(s)

Question: Which of the following code snippets will compile without any errors?

(Assume that the statement int x = 0; exists prior to the statements below.)

Select 3 option(s)

Question: Given:

public static void createFile(String name) throws Exception{
try (
OutputStream os = new FileOutputStream(name); ) {

//INSERT CODE HERE

//flush and close the streams that are open
}

}

Which of the following combinations of the lines of code and their outcome when inserted above, are correct?

Select 2 option(s)

Question: You are creating a abc.payroll module that makes its two classes - com.abc.payroll.Hourly and com.abc.payroll.Yearly - available to all other modules for use.

Which of the following files correctly defines this module?

Select 1 option(s)

Question: What will the following program print?

public class TestClass{
static int someInt = 10;
public static void changeIt(int a){
a = 20;
}
public static void main(String[] args){
changeIt(someInt);
System.out.println(someInt);
}
}

Select 1 option(s)

Question: Given:

public class Course{
private String id;
private String category;

public Course(String id, String category){
this.id = id; this.category = category;
}

public String toString(){
return id+" "+category;
}

//accessors not shown
}

What will the following code print?

List s1 = Arrays.asList(
new Course("OCAJP", "Java"),
new Course("OCPJP", "Java"),
new Course("C#", "C#"),
new Course("OCEJPA", "Java")
);

s1.stream()
.collect(Collectors.groupingBy(c->c.getCategory()))
.forEach((m, n)->System.out.println(n));

Select 1 option(s)

Question: Given the following classes, what will be the output of compiling and running the class Truck?

class Automobile{
public void drive() { System.out.println("Automobile: drive"); }
}

public class Truck extends Automobile{
public void drive() { System.out.println("Truck: drive"); }
public static void main (String args [ ]){
Automobile a = new Automobile();
Truck t = new Truck();
a.drive(); //1
t.drive(); //2
a = t; //3
a.drive(); //4
}
}

//End of Code

Select 1 option(s)

Question: What will the following code print?

List s1 = new ArrayList();
String s = null;
s1.add("a");
s1.add(s); //1
s1.add("b");
s1.remove(s); //2
System.out.println(s1); //3

Select 1 option(s)

Question: Consider the following code:

public class FileCopier {
public static void copy(String records1, String records2) {
try {
InputStream is = new FileInputStream(records1);
OutputStream os = new FileOutputStream(records2);
byte[] buffer = new byte[1024];
int bytesRead = 0;
while ((bytesRead = is.read(buffer)) != -1) {
os.write(buffer, 0, bytesRead);
System.out.println("Read and written bytes " + bytesRead);
}
} catch (FileNotFoundException | IndexOutOfBoundsException e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
copy("c:\\temp\\test1.txt", "c:\\temp\\test2.txt");
}
}

Assuming appropriate import statements and the existence of both the files, what will happen when the program is compiled and run?

Select 1 option(s)

Question: Which of the following method implementations will write a boolean value to the underlying stream?

Select 3 option(s)

Question: Consider the following code written to generate a report containing customer data where each line is a pipe separated list of values.

String qr = "select EMAILID, NAME, PHONE from CUSTOMER order by EMAILID";
PreparedStatement stmt = connection.prepareStatement(qr);
ResultSet rs = stmt.executeQuery(); //LINE 10
while(rs.next()){
System.out.println(rs.getString(0)+"|"+rs.getString(1)+"|"+rs.getString(3));
}
connection.close();

Identify the correct statement about this code.

(Assume that items not specified such as import statements and try/catch block are all valid.)

Select 1 option(s)

Question: The signature of a method in a class is as follows:

public static List doIt(List nums)

This method is being called in the following code:

result = doIt(in);

Given that String implements CharSequence interface, what should be the reference type of 'in' and 'result' variables?

Select 1 option(s)

Question: Given:

@Retention(RetentionPolicy.RUNTIME)
public @interface DebugInfo {
String[] params() default {""};
String date() default "";
int depth() default 10;
String value() ;
}

Which of the following options correctly uses the above annotation?

Select 3 option(s)

Question: Consider the following class hierarchy.

class A{
public void m1() { }
}
class B extends A{
public void m1() { }
}
class C extends B{
public void m1(){
/* //1
... lot of code.
*/
}
}

Select 2 option(s)

Question: Consider the following code:

Statement stmt = null;
try(Connection c = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app"))
{
stmt = c.createStatement();
ResultSet rs = stmt.executeQuery("select * from STUDENT");
while(rs.next()){
System.out.println(rs.getString(1));
}

}
catch(SQLException e){
System.out.println("Exception "+e);
}

Which objects can be successfully used to query the database after the try block ends without any exception?

Select 1 option(s)

Question: Given:

public class Book{
private int id;
private String title;
//constructors and accessors not shown
}

Assuming that book is a reference to a valid Book object, which of the following code fragments correctly prints the details of the Book?

Select 1 option(s)

Question: What will be the output when the following class is compiled and run?

class ScopeTest{
static int x = 5;
public static void main(String[] args){
int x = ( x=3 ) * 4; // 1
System.out.println(x);
}
}

Select 1 option(s)

Question: Given that the file test.txt contains:

12345678

What will the following code print when compiled and run?

public static void main(String[] args) throws Exception{
try(var fis = new FileInputStream("c:\\temp\\test.txt");
var isr = new InputStreamReader(fis)){
while(isr.ready()){
isr.skip(1);
int i = isr.read();
char c = (char) i;
System.out.print(c);
}
}
}

Select 1 option(s)

Question: Identify correct statements about the following code:

import java.util.*;

class Student{
int marks;
}

class TestClass {
var k = new Student(); //1

public static void main(String[] args) {

var s = new Student(){ //2
@Override
public String toString(){ return "student obj"; };
};

var slist = Set.of(new Student()); //3

for(var i : slist){ //4
System.out.println(i);
}

slist.removeIf((var s1) -> s1.marks<0); //5
}
}

Select 1 option(s)

Question: What will the following code print when compiled and run?

HashSet keys = new HashSet(List.of("a", "b", "c"));
ArrayList values = new ArrayList(Set.of("1", "2", "3"));

Map m = new HashMap();
int i = 0;
for(var key : keys){
m.put(key, values.get(i++));
}
keys.clear(); //2
values.clear();
System.out.println(m.keySet().size()+" "+m.values().size());

Select 1 option(s)

Question: Given:

public static void createFile(String name) throws Exception{
try (
OutputStream os = new FileOutputStream(name); ) {

//INSERT CODE HERE

//flush and close the streams that are open
}

}

Which of the following combinations of the lines of code and their outcome when inserted above, are correct?

Select 2 option(s)

Question: Given:

var qr = "insert into USERINFO values( ?, ?, ?)";
try(PreparedStatement ps = c.prepareStatement(qr);)
{
ps.setObject(1, 1, JDBCType.INTEGER);
ps.setObject(2, "Ally A", JDBCType.VARCHAR);
ps.setObject(3, "101 main str", JDBCType.VARCHAR);
var i = ps.executeUpdate(); //1
ps.setObject(1, 2, JDBCType.INTEGER);
ps.setObject(2, "Bob B", JDBCType.VARCHAR);
i = ps.executeUpdate(); //2
}

What will be the result?

Select 1 option(s)

Question: What will the following program print when compiled and run?

class Boo implements Serializable {
transient int ti = 10;
static int si = 20;
}

public class TestClass
{
public static void main(String[] args) throws Exception
{

Boo boo = new Boo();
boo.si++;
System.out.println(boo.ti+" "+boo.si);
var fos = new FileOutputStream("c:\\temp\\boo.ser");
var os = new ObjectOutputStream(fos);
os.writeObject(boo);
os.close();

var fis = new FileInputStream("c:\\temp\\boo.ser");
var is = new ObjectInputStream(fis);
boo = (Boo) is.readObject();
is.close();
System.out.println(boo.ti+" "+boo.si);
}
}

Select 1 option(s)

Question: Given the following code that appears inside a method:

var values = new ArrayList();
//INSERT CODE HERE

What can be inserted at the given location without causing any compilation error?

Select 2 option(s)

Question: Consider the following two classes (in the same package but defined in different source files):

public class Square {
double side = 0;
double area;

public Square(double length){ this.side = length; }

public double getSide() { return side; }

public void setSide(double side) { this.side = side; }

double getArea() { return area; }
}
public class TestClass {
public static void main(String[] args) throws Exception {
Square sq = new Square(10.0);
sq.area = sq.getSide()*sq.getSide();
System.out.println(sq.getArea());
}
}
You are assigned the task of refactoring the Square class to make it better in terms of encapsulation. What changes will you make to this class?

Select 2 option(s)

Question: You have a file named customers.dat in c:\company\records directory. You want to copy all the lines in this file to another file named clients.dat in the same directory and you have the following code to do it:

public static void writeData() {
Path p1 = Paths.get("c:\\company\\records\\customers.dat");

//LINE 20 - INSERT CODE HERE

try (
var br = new BufferedReader(new FileReader(p1.toFile()));
var bw = new BufferedWriter(new FileWriter(p2.toFile()))) {
String line = null;
while ((line = br.readLine()) != null) {

bw.write(line);
bw.newLine();
}
}catch(Exception e){
e.printStackTrace();
}
}

Which of the following options can be inserted independent of each other at //LINE 20 to make it work?

Assume that the current directory for the program when it runs is c:\code.

Select 2 option(s)

Question: Given:

public class TestClass {
public void myMethod(String... params) {
var a = params;
var b = params[0];
}
}

What are the types of the variables a and b?

Select 1 option(s)

Question: Given:

module abc.print{
requires org.pdf;
provides org.pdf.Print with com.abc.print.PrintImpl;
}

Identify correct statements about the above module.

Select 1 option(s)

Question: Given:

package loops;
public class JustLooping {
private int j;
void showJ(){
while(j<=5){
for(int j=1; j <= 5;){
System.out.print(j+" ");
j++;
}
j++;
}
}
public static void main(String[] args) {
new JustLooping().showJ();
}
}

What is the result?

Select 1 option(s)

Question: Which statements about the following code contained in BankAccount.java are correct?

interface Account{
public default String getId(){
return "0000";
}
}

interface PremiumAccount extends Account{
public String getId();
}

public class BankAccount implements PremiumAccount{
public static void main(String[] args) {
Account acct = new BankAccount();
System.out.println(acct.getId());
}

}

Select 1 option(s)

Question: Which of the following method definitions will prevent overriding of that method?

Select 4 option(s)

Question: Consider the following class...

class TestClass{
void probe(Object x) { System.out.println("In Object"); } //3

void probe(Number x) { System.out.println("In Number"); } //2

void probe(Integer x) { System.out.println("In Integer"); } //2

void probe(Long x) { System.out.println("In Long"); } //4

public static void main(String[] args){
double a = 10;
new TestClass().probe(a);
}
}

What will be printed?

Select 1 option(s)

Question: Which of the following lines will cause the compilation to fail?

interface I { }

public enum EnumA implements I, Serializable { A, AA, AAA}; //1


class TestClass
{
public enum EnumB{ B, BB, BBB;
public Object clone(){ return B; } //2
}

public static enum EnumC{ C, CC, CCC };

public static enum EnumD extends EnumC{ DDD }; //3

public TestClass()
{
System.out.println(EnumC.CC.index()); //4
}


public static void main(String[] args)
{
System.out.println(EnumC.valueOf("ccc")); //5
System.out.println(EnumC.CCC.name()); //6
}
}

Select 3 option(s)

Question: Given:

module broker{
exports org.broker.api;
}

The broker module contains org.broker.api.Installer interface, which is implemented by com.foo.AppInstaller class of com.foo module.

Which of the following is a valid module definition for com.foo module?

Select 1 option(s)

Question: Given:

interface Process{
public void process(int a, int b);
}

public class Data{
int value;
Data(int value){
this.value = value;
}
}

and the following code fragments:
public void processList(ArrayList dataList, Process p){
for(Data d: dataList){
p.process(d.value, d.value);
}
}

....
ArrayList al = new ArrayList();
al.add(new Data(1));al.add(new Data(2));al.add(new Data(3));

//INSERT METHOD CALL HERE

Which of the following options can be inserted above so that it will print 1 4 9?

Select 3 option(s)