Java Programming/Statements/if

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The if ... else statement is used to conditionally execute one of two statements, depending on the result of a boolean condition.


if (list == null) {
  {{Java://|this block of statements executes if the condition is true
else {
  {{Java://|this block of statements executes if the condition is false

An if statement has two forms:

if (boolean-condition)


if (boolean-condition)

Use the second form if you have different statements to execute if the boolean-condition is true or if it is false. Use the first if you only wish to execute statement1 if the condition is true and you do not wish to execute alternate statements if the condition is false.

The following example calls two int methods, f() and f(), stores the results, then uses an if statement to test if x is less than y and if it is, the statement1 body will swap the values. The end result is x always contains the larger result and y always contains the smaller result.

int x = f();
int y = y();
if ( x < y ) {
  int z = x;
  x = y;
  y = z;