Java java core 1 quiz

What is the outcome?

int value = (int) 2.0 / 3.0;
System.out.println(value);

What is wrong with this code?

public String readLine() {
    try {
      BufferedReader br = 
         new BufferedReader(new FileReader("file.txt"));
      String line = br.readLine();
      br.close();
      return line;
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
}

What will be printed?

int i = 255;
byte b = (byte) i;
System.out.println(b);

What will be printed?

double value = -0.0;
System.out.println(value);

What will be printed?

boolean value = -0.0 == 0.0;
System.out.println(value);

What will be printed?

boolean value = Double.NaN == Double.NaN;
System.out.println(value);

What will be printed?

boolean value = 
  Double.POSITIVE_INFINITY == Double.POSITIVE_INFINITY;
System.out.println(value);

What will be printed?

int a = -1;
a = a >> 1;
System.out.println(a);

What will be printed?

int a = -1;
a = a >>> 1;
System.out.println(a);

What will be printed?

byte b = (byte) 128;
b >>>= 1;
System.out.println(b);

What will be the result of executing this code?

String s = null;
if ((s != null) || (!s.isEmpty())) {
  System.out.println(s);
} else {
  System.out.println("the string is null");
}

What will be printed?

String s1 = new String("a");
String s2 = new String("a");
System.out.println(s1 == s2);

What will be the result of running this code?

public class Test {
  static boolean printAndReturn(boolean value) {
    System.out.println(value);
    return value;
  }
  public static void main(String[] args) {
    if (printAndReturn(false) && printAndReturn(true)) {
      System.out.println(true);
    } else {
      System.out.println(false);
    }
  }
}

What will be printed?

int a = 1;
a += ++a * a;
System.out.println(a);

What will be printed?

String s1 = "a";
String s2 = "a";
System.out.println(s1 == s2);

What will be printed?

String s1 = "a";
String s2 = s1;
s1 += "b";
System.out.println(s2);

What will be printed?

int a = 10;
System.out.println(a + ~a);

What will be the output of the program?

String a = "newspaper";
a = a.substring(5,7);
char b = a.charAt(1);
a = a + b;
System.out.println(a);

What will be the output of the program?

String a = "ABCD"; 
String b = a.toLowerCase(); 
b.replace('a','d'); 
b.replace('b','c'); 
System.out.println(b);

Which of the following is true?

public final class Main {
  static final String s = "hello";
  public void main(String[] args) {
    System.out.println(s);
  }
}