Java · Theory

Java Operators

Theory

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Java Operators

Operators do work on values. + - * / % for maths. % is remainder — handy for even/odd. 5 / 2 is 2 in int maths, not 2.5. That surprise fails many viva questions.

> < >= <= == != compare and give true or false. && || ! join conditions. = assigns. == compares. x += 1 is x = x + 1.

condition ? a : b is a short if-else. The classic bug is writing = inside if when you meant ==. In an exam, show both traps: = vs ==, and 5/2 becoming 2.

Let's take this on the board with one tiny Main class — no extra files. Java Operators — output: 1 then true. 10 % 3 is 1. 10 > 3 && 3 > 0 is true. Start from main, go line by line, and stop at each print. That output is the proof for Operators.

Exam tip

Show two traps: = vs ==, and 5/2 becoming 2 (int division).

Example

public class Main {
  public static void main(String[] args) {
    int a = 10, b = 3;
    System.out.println(a % b);
    System.out.println(a > b && b > 0);
  }
}

Java Operators — output: 1 then true. 10 % 3 is 1. 10 > 3 && 3 > 0 is true.

Short notes

DefOperators do work on values — maths, compare, assign, join conditions.
Rule% = remainder. 5 / 2 → 2 in int maths, not 2.5.
Diff= assigns. == compares.
TrapWriting = inside if when you meant ==.

Java · Theory

Java Operators

← All stacks

Theory

13/270

Java Operators

Operators do work on values. + - * / % for maths. % is remainder — handy for even/odd. 5 / 2 is 2 in int maths, not 2.5. That surprise fails many viva questions.

> < >= <= == != compare and give true or false. && || ! join conditions. = assigns. == compares. x += 1 is x = x + 1.

condition ? a : b is a short if-else. The classic bug is writing = inside if when you meant ==. In an exam, show both traps: = vs ==, and 5/2 becoming 2.

Exam tip

Show two traps: = vs ==, and 5/2 becoming 2 (int division).

Example

public class Main {
  public static void main(String[] args) {
    int a = 10, b = 3;
    System.out.println(a % b);
    System.out.println(a > b && b > 0);
  }
}

Java Operators — output: 1 then true. 10 % 3 is 1. 10 > 3 && 3 > 0 is true.

Short notes

DefOperators do work on values — maths, compare, assign, join conditions.
Rule% = remainder. 5 / 2 → 2 in int maths, not 2.5.
Diff= assigns. == compares.
TrapWriting = inside if when you meant ==.

Java Operators

Example

Short notes

Questions

Java Operators

Example

Short notes

Questions