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