LeftCurly

Since Checkstyle 3.0

Description

Checks for the placement of left curly braces ('{') for code blocks.

Properties

name	description	type	default value	since
ignoreEnums	Allow to ignore enums when left curly brace policy is EOL.	boolean	`true`	6.9
option	Specify the policy on placement of a left curly brace (`'{'`).	LeftCurlyOption	`eol`	3.0
tokens	tokens to check	subset of tokens ANNOTATION_DEF , CLASS_DEF , CTOR_DEF , ENUM_CONSTANT_DEF , ENUM_DEF , INTERFACE_DEF , LAMBDA , LITERAL_CASE , LITERAL_CATCH , LITERAL_DEFAULT , LITERAL_DO , LITERAL_ELSE , LITERAL_FINALLY , LITERAL_FOR , LITERAL_IF , LITERAL_SWITCH , LITERAL_SYNCHRONIZED , LITERAL_TRY , LITERAL_WHILE , METHOD_DEF , OBJBLOCK , STATIC_INIT , RECORD_DEF , COMPACT_CTOR_DEF .	ANNOTATION_DEF , CLASS_DEF , CTOR_DEF , ENUM_CONSTANT_DEF , ENUM_DEF , INTERFACE_DEF , LAMBDA , LITERAL_CASE , LITERAL_CATCH , LITERAL_DEFAULT , LITERAL_DO , LITERAL_ELSE , LITERAL_FINALLY , LITERAL_FOR , LITERAL_IF , LITERAL_SWITCH , LITERAL_SYNCHRONIZED , LITERAL_TRY , LITERAL_WHILE , METHOD_DEF , OBJBLOCK , STATIC_INIT , RECORD_DEF , COMPACT_CTOR_DEF .	3.0

Examples

To configure the check:


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

Example:


class Example1
{ // violation, ''{' at column 1 should be on the previous line.'
  private interface TestInterface
  { // violation, ''{' at column 3 should be on the previous line.'
  }

  private
    class
    MyClass { // OK
  }

  enum Colors {RED, // OK
    BLUE,
    GREEN;
  }
}

To configure the check to apply the nl policy to type blocks:


<module name="Checker">
  <module name="TreeWalker">
    <module name="LeftCurly">
      <property name="option" value="nl"/>
      <property name="tokens" value="CLASS_DEF,INTERFACE_DEF"/>
    </module>
  </module>
</module>

Example:


class Example2
{ // OK
  private interface TestInterface
  { // OK
  }

  private
    class
    MyClass { // violation, ''{' at column 13 should be on a new line.'
  }

  enum Colors {RED, // OK
    BLUE,
    GREEN;
  }
}

To configure the check to apply the nlow policy to type blocks:


<module name="Checker">
  <module name="TreeWalker">
    <module name="LeftCurly">
      <property name="option" value="nlow"/>
      <property name="tokens" value="CLASS_DEF,INTERFACE_DEF"/>
    </module>
  </module>
</module>

Example:


class Example3
{ // violation, ''{' at column 1 should be on the previous line.'
  private interface TestInterface { // OK
  }

  private
    class
    MyClass { // violation, ''{' at column 13 should be on a new line.'
  }

  enum Colors {RED, // OK
    BLUE,
    GREEN;
  }
}

An example of how to configure the check to validate enum definitions:


<module name="Checker">
  <module name="TreeWalker">
    <module name="LeftCurly">
      <property name="ignoreEnums" value="false"/>
    </module>
  </module>
</module>

Example:


class Example4
{ // violation, ''{' at column 1 should be on the previous line.'
  private interface TestInterface
  { // violation, ''{' at column 3 should be on the previous line.'
  }

  private
    class
    MyClass { // OK
  }

  enum Colors {RED, // violation, ''{' at column 15 should have line break after.'
    BLUE,
    GREEN;
  }
}

Example of Usage

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.blocks

Parent Module

TreeWalker