Class DeclarationOrderCheck

All Implemented Interfaces:
Configurable, Contextualizable

public class DeclarationOrderCheck extends AbstractCheck

Checks that the parts of a class, record, or interface declaration appear in the order suggested by the Code Conventions for the Java Programming Language.

According to Code Conventions for the Java Programming Language, the parts of a class or interface declaration should appear in the following order:

  1. Class (static) variables. First the public class variables, then protected, then package level (no access modifier), and then private.
  2. Instance variables. First the public class variables, then protected, then package level (no access modifier), and then private.
  3. Constructors
  4. Methods

Purpose of ignore* option is to ignore related violations, however it still impacts on other class members.

ATTENTION: the check skips class fields which have forward references from validation due to the fact that we have Checkstyle's limitations to clearly detect user intention of fields location and grouping. For example:

 public class A {
   private double x = 1.0;
   private double y = 2.0;
   public double slope = x / y; // will be skipped from validation due to forward reference
 }
 
  • Property ignoreConstructors - control whether to ignore constructors. Type is boolean. Default value is false.
  • Property ignoreModifiers - control whether to ignore modifiers (fields, ...). Type is boolean. Default value is false.

To configure the check:

 <module name="DeclarationOrder"/>
 

With default options:

 class K {
   int a;
   void m(){}
   K(){}  <-- "Constructor definition in wrong order"
   int b; <-- "Instance variable definition in wrong order"
 }
 

With ignoreConstructors option:

 class K {
   int a;
   void m(){}
   K(){}
   int b; <-- "Instance variable definition in wrong order"
 }
 

With ignoreConstructors option and without a method definition in a source class:

 class K {
   int a;
   K(){}
   int b; <-- "Instance variable definition in wrong order"
 }
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • declaration.order.access
  • declaration.order.constructor
  • declaration.order.instance
  • declaration.order.static
Since:
3.2
  • Field Details

    • MSG_CONSTRUCTOR

      public static final String MSG_CONSTRUCTOR
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:
    • MSG_STATIC

      public static final String MSG_STATIC
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:
    • MSG_INSTANCE

      public static final String MSG_INSTANCE
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:
    • MSG_ACCESS

      public static final String MSG_ACCESS
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:
  • Constructor Details

    • DeclarationOrderCheck

      public DeclarationOrderCheck()
  • Method Details

    • getDefaultTokens

      public int[] getDefaultTokens()
      Description copied from class: AbstractCheck
      Returns the default token a check is interested in. Only used if the configuration for a check does not define the tokens.
      Specified by:
      getDefaultTokens in class AbstractCheck
      Returns:
      the default tokens
      See Also:
    • getAcceptableTokens

      public int[] getAcceptableTokens()
      Description copied from class: AbstractCheck
      The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.
      Specified by:
      getAcceptableTokens in class AbstractCheck
      Returns:
      the token set this check is designed for.
      See Also:
    • getRequiredTokens

      public int[] getRequiredTokens()
      Description copied from class: AbstractCheck
      The tokens that this check must be registered for.
      Specified by:
      getRequiredTokens in class AbstractCheck
      Returns:
      the token set this must be registered for.
      See Also:
    • beginTree

      public void beginTree(DetailAST rootAST)
      Description copied from class: AbstractCheck
      Called before the starting to process a tree. Ideal place to initialize information that is to be collected whilst processing a tree.
      Overrides:
      beginTree in class AbstractCheck
      Parameters:
      rootAST - the root of the tree
    • visitToken

      public void visitToken(DetailAST ast)
      Description copied from class: AbstractCheck
      Called to process a token.
      Overrides:
      visitToken in class AbstractCheck
      Parameters:
      ast - the token to process
    • leaveToken

      public void leaveToken(DetailAST ast)
      Description copied from class: AbstractCheck
      Called after all the child nodes have been process.
      Overrides:
      leaveToken in class AbstractCheck
      Parameters:
      ast - the token leaving
    • setIgnoreConstructors

      public void setIgnoreConstructors(boolean ignoreConstructors)
      Setter to control whether to ignore constructors.
      Parameters:
      ignoreConstructors - whether to ignore constructors.
    • setIgnoreModifiers

      public void setIgnoreModifiers(boolean ignoreModifiers)
      Setter to control whether to ignore modifiers (fields, ...).
      Parameters:
      ignoreModifiers - whether to ignore modifiers.