Test de DSE

Which of the following statements are true?

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?

Consider the following program:
class Point2D {
private int x, y;
public Point2D(int x, int y) {
x = x;
}
public String toString() {
return "[" + x + ", " + y + "]";
}
public static void main(String[] args) {
Point2D point = new Point2D(10, 20);
System.out.println(point);
}
}
Which one of the following options provides the output of this program when executed?

Given:
public static void main(String[] args) {
double a = 2 + 5 * 6 / 7.0 % 6 + 7 - 9;
System.out.println(a);
}
What is the result?

What will be result of attempting to compile this class?
import java.util.*;
package test;
public class TestClass {
public OtherClass oc = new OtherClass();
}
class OtherClass {
int value;
}

Given:
public class SuperLoop3 {
public static void main(String[] args) {
int suma = 0;
for (int i = 0, j = 9, z = 1; i < 4 && j > 0; i++, --j, j--) {
do {
suma += i * j % z + 3;
} while (z++ <= 1);
}
System.out.println("suma:: " + suma);
}
}
What is the result?

Given:
class Test {
public static void main(String[] args) {
int var = 3;
switch (var) {
case 1:
try {
throw new IllegalArgumentException();
} catch (RuntimeException e) {
e.printStackTrace();
}
default:
try {
throw new ArrayIndexOutOfBoundsException();
} catch (RuntimeException e) {
e.printStackTrace();
}
case 2:
try {
throw new ArithmeticException();
} catch (RuntimeException e) {
e.printStackTrace();
}
}
}
}
What is the result?

Given:
public class Foo {
public static void main(String[] args) {
int a = 10;
long b = 20;
short c = 30;
System.out.println(++a + b++ * c);
}
}

class EJavaGuruStringBuilder {
public static void main(String args[]) {
StringBuilder ejg = new StringBuilder(10 + 2 + "SUN" + 4 + 5);
ejg.append(ejg.delete(3, 6));
System.out.println(ejg);
}
}
What is the output of the following code?