What does “?” mean in Java? [duplicate]

Answer 1

It is called conditional operator.This is how it works. if min is greater than or equal to 2 ,then first value after ? that is 2 here will be assign to corresponding variable ,otherwise second value that is 1 here will be assign.

Answer 2

This link will tell you all you need.

Summary for archival sakes:

It's called the conditional operator. It's a ternary operator that takes three terms:

BooleanExpression ? Expr1 : Expr2

The BooleanExpressionis evaluated. If it's true, the value of the whole expression is Expr1. If it's false, the value of the whole expression is Expr2.

So it serves the same kind of purpose as an if statement, but it's a term rather than a whole statement. That means you can embed it in places where you can't use a whole statement.

Answer 3

That's a Ternary Operator. Check Oracle's doc for further info. Long story short, it is an if-else statement that can be done in a single line and used inside methods and to define variable values.

Syntax:

boolean_expression ? do_if_true : do_if_false;

Parallelism with if-else statement:

if(boolean_expression)
    //do_if_true;
else 
    //do_if_false;

I didn't use brackets on purpose, since you can only execute one line of code in do_if_true and do_if_false.

Example of use:

boolean hello = true;
String greetings = hello ? "Hello World!" : "No hello for you...";

This will set someString as "Hello World!" since the boolean variable hello evaluates to true. On the other hand, you can nest this expressions:

boolean hello = true;
boolean world = false;

String greetings = hello ? (world ? "Hello World!" : "Hello Stranger!") : "No hello for you...";

In this case, greetings will have as a value "Hello Stranger!";

Answer 4

someval = (min >= 2) ? 2 : 1;

This is called ternary operator, which can be used as if-else. this is equivalent to

if((min >= 2) {
   someval =2;
} else {
   someval =1
}

Follow this tutorial for more info and usage.

Answer 5

Its ternary operator also referred to as the conditional operator, have a look reference

like Object bar = foo.isSelected() ? getSelected(foo) : getSelected(baz);

eg. operand1 ? operand2 : operand3

• if operand1 is true, operand2 is returned, else operand3 is returned
• operand1 must be a boolean type
• operand1 can be an expression that evaluates to a boolean type
• operand1 and operand2 must be promotable numeric types or castable object references, or null
• if one of operand2 or operand3 is a byte and the other a short, the type of the returned value will be a short
• if one of operand2 or operand3 is a byte, short or char and the other is a constant int value which will fit within the other operands range, the type of the returned value will be the type of the other operand
• otherwise, normal binary numeric promotion applies
• if one of operand2 or operand3 is a null, the type of the return will be the type of the other operand
• if both operand2 and operand3 are different types, one of them must be compatible (castable) to the other type reference

Answer 6

It's called the Ternary If operator, it's just short-hand for an if...else