Infosys Certified Java Programmer

Predict the output of the following code snippet:

public class TestDemo {

public static void main(String[] args) {
try {
Marks(4);
Marks(3);
Marks(2);
Marks(1);
} catch (ArrayIndexOutOfBoundsException e) {
System.out.println("Array index is out of bounds at main");
}
}

public static void Marks(int x) {
int marks[][] = {{10, 20}, {9, 12}, {8, 16}, {7, 15}};
int total[] = {0, 0, 0, 0};
try {
total[x] = (marks[x][0] + marks[x][1]);
System.out.println(total[x]);

} catch (ArrayIndexOutOfBoundsException e) {
System.out.println("Array index is out of bounds at method");
}

}

}

What will be the output of the following code when executed?
public class StringTester{
public static void main(String[] args){
String str1=null;
String str2=new String(“null”);
System.out.println(“null”.equals(str1));
System.out.println(“null”.equals(str2));
System.out.println(str1.equals(null));
}
}

What will be the output of the following code?

public class BaseClass {

private int display1(int i)

{ return i++ + --i; }

public int display2(int i)

{ return display1(--i + 1); }

}

class ChildClass extends BaseClass

{

int display1(int i) // Line1

{ return display2(++i + ++i + --i); // Line2 }

}

class MainClass {

public static void main(String[] args) {

System.out.println("Value is " + new ChildClass().display1(27));

}}

Which of the following are valid Functional Interfaces?(Choose any 3)

What is the output of the following code?
interface Test {

void display();
}

class Figure implements Test {

public void display()//line 1
{
System.out.println("Inside class Figure");
}
}

public class ChildFigure extends Figure {//line 2

public void display() {
System.out.println("Inside class ChildFigure");
}

public static void main(String args[]) {
Test ref = new ChildFigure();
ref.display();
Figure obj = (Figure) ref;//line 3
obj.display();
}
}

What will be the output of the code given below?

public static void main(String[] args) {

LocalDateTime date1 = LocalDateTime.now();

System.out.println(date1.isAfter(date1.plusDays(1)));

}

Given student table:

stuId stuName

----- -------

1001 Jack

1002 Jill

1003 John

1004 Jason

Given code snippet:

ResultSet resultSet = statement.executeQuery("select * from student");

while(resultSet.hasNext()) {

resultSet.next();

String stuName = resultSet.getString(2);

System.out.print(stuName + " ");

resultSet.next();

}

What will be the output?

For the given code, if con is a valid Connection object, and the table Customer is empty, what will be output of this code?

try {
con = DriverManager.getConnection(url,uid,pwd);
Statement stmnt = con.createStatement();
rs = stmnt.executeQuery("select * from customer");
if (rs.next())
rs.getString(2);
} catch (SQLException e) {
e.printStackTrace();
}

Which out of the following are true in regard to interfaces in Java ?(Select two)

Refer the below code snippet and predict the outcome.

public static void main(String args[]){
Integer intVar1 = null;
Integer intVar2 = new Integer(110);
Optional<Integer> optinalVar1 = Optional.ofNullable(intVar1);
Optional<Integer> optinalVar2 = Optional.of(intVar2);
System.out.println(optinalVar1.orElse(new Integer(0))+optinalVar2.get()); // Line9
}