ArrayBracketNoWhitespace

Since Checkstyle 13.1.0

Description

Checks that the whitespace around square-bracket tokens [ and ] follows the typical Java convention for array declarations, array creation, and array indexing.

Left square bracket ("["):

must not be preceded with whitespace when preceded by a TYPE or IDENT in array declarations or array access
must not be followed with whitespace

Right square bracket ("]"):

must not be preceded with whitespace
must be followed with whitespace in all cases, except when followed by:
- another bracket: [][]
- a dot for member access: arr[i].length
- a comma or semicolon: arr[i], or arr[i];
- postfix operators: arr[i]++ or arr[i]--
- a right parenthesis or another closing construct: (arr[i])

Examples

To configure the check:


<module name="Checker">
  <module name="TreeWalker">
    <module name="ArrayBracketNoWhitespace"/>
  </module>
</module>

Examples with incorrect array bracket whitespace:


class Example1 {
  int array1[] ; // violation, space before ;
  int array2[ ] = new int[ 5 ]; // 3 violations, space in [] and before ;
  int[] array3 = new int[5 ]; // violation, space before ]
  int array4 [] = new int [ 5 ] ;
  // 5 violations, space after variable name, in all []
  int array5
    [ ]
    =
    new int
    [ 1 ] ; // violations, space in []
  void method1(int param[ ]) { // violation, space in []
  }
  void method2() {
    int arr [  ] = { 1, 2, 3 }; // violations, spaces in []
  }
}

Examples without violations:


class Example2 {
  int[] array1;
  int[] array2 = new int[5];
  int[] array3 = new int[]{1, 2, 3};
  void method1(int[] param) {
  }
  void method2() {
    int[] arr = { 1, 2, 3 };
  }
}

Example of Usage

Checkstyle Style

Violation Messages

All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.

Package

com.puppycrawl.tools.checkstyle.checks.whitespace

Parent Module

TreeWalker