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java equivalent of Delphi NOT

In Delphi I can do the following with a boolean variable:

If NOT bValue then
begin
  //开发者_如何学编程do some stuff
end;

Does the equivalent in Java use the !?

If !(bValue) {
  //do some stuff
}


You're close; the proper syntax is:

if (!bValue) {
  //do some stuff
}

The entire conditional expression must be inside the parenthesis; the condition in this case involve the unary logical complement operator ! (JLS 15.15.6).

Additionally, Java also has the following logical binary operators:

  • JLS 15.22.2 Boolean Logical Operators &, ^ and |
    • casually "and", "xor" and "or"
  • JLS 15.23 Conditional-and && and JLS 15.24 Conditional-or ||
    • the much more frequently used short-circuiting "and" and "or"

There are also compound assignment operators (JLS 15.26.2) &=, |=, ^=.


Other relevant questions on stackoverflow:

  • Shortcut "or-assignment" (|=) operator in Java
  • Why doesn’t Java have compound assignment versions of the conditional-and and conditional-or operators? (&&=, ||=)
  • What’s the difference between | and || in Java?
  • Cleanest way to toggle a Boolean variable in Java?
  • Getting confused in with == and = in “if” statement
    • There are plenty of similar questions on stackoverflow due to accidental boolean assignment instead of comparison
    • You never need to write == true and == false
      • Omit explicit comparison with true and false
      • use ! when necessary


Yes, but inside the bracket:

if (!bValue) {
}

You'd normally not use any sort of data type prefix in Java as well, so it would more likely be something like:

if (!isGreen) { // or some other meaningful variable name
}


if (!bValue) {
    // do some stuff
}
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