com.puppycrawl.tools.checkstyle.checks.coding

Class DeclarationOrderCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.puppycrawl.tools.checkstyle.checks.coding.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"/>
 

Example:

 public class Test {

   public int a;
   protected int b;
   public int c;            // violation, variable access definition in wrong order

   Test() {
     this.a = 0;
   }

   public void foo() {
     // This method does nothing
   }

   Test(int a) {            // violation, constructor definition in wrong order
     this.a = a;
   }

   private String name;     // violation, instance variable declaration in wrong order
 }
 

To configure the check to ignore validation of constructors:

 <module name="DeclarationOrder">
   <property name="ignoreConstructors" value="true"/>
 </module>
 

Example:

 public class Test {

   public int a;
   protected int b;
   public int c;            // violation, variable access definition in wrong order

   Test() {
     this.a = 0;
   }

   public void foo() {
     // This method does nothing
   }

   Test(int a) {            // OK, validation of constructors ignored
     this.a = a;
   }

   private String name;     // violation, instance variable declaration in wrong order
 }
 

To configure the check to ignore modifiers:

 <module name="DeclarationOrder">
   <property name="ignoreModifiers" value="true"/>
 </module>
 

Example:

 public class Test {

   public int a;
   protected int b;
   public int c;            // OK, access modifiers not considered while validating

   Test() {
     this.a = 0;
   }

   public void foo() {
     // This method does nothing
   }

   Test(int a) {            // violation, constructor definition in wrong order
     this.a = a;
   }

   private String name;     // violation, instance variable declaration 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

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	DeclarationOrderCheck.ScopeState Private class to encapsulate the state.

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Set<java.lang.String>	classFieldNames Set of all class field names.
private boolean	ignoreConstructors Control whether to ignore constructors.
private boolean	ignoreModifiers Control whether to ignore modifiers (fields, ...).
static java.lang.String	MSG_ACCESS A key is pointing to the warning message text in "messages.properties" file.
static java.lang.String	MSG_CONSTRUCTOR A key is pointing to the warning message text in "messages.properties" file.
static java.lang.String	MSG_INSTANCE A key is pointing to the warning message text in "messages.properties" file.
static java.lang.String	MSG_STATIC A key is pointing to the warning message text in "messages.properties" file.
private java.util.Deque<DeclarationOrderCheck.ScopeState>	scopeStates List of Declaration States.
private static int	STATE_CTOR_DEF State for the CTOR_DEF.
private static int	STATE_INSTANCE_VARIABLE_DEF State for the VARIABLE_DEF.
private static int	STATE_METHOD_DEF State for the METHOD_DEF.
private static int	STATE_STATIC_VARIABLE_DEF State for the VARIABLE_DEF.

Constructor Summary

Constructors

Constructor and Description
DeclarationOrderCheck()

Method Summary

Modifier and Type	Method and Description
void	beginTree(DetailAST rootAST) Called before the starting to process a tree.
int[]	getAcceptableTokens() The configurable token set.
private static java.util.Set<DetailAST>	getAllTokensOfType(DetailAST ast, int tokenType) Collects all tokens of specific type starting with the current ast node.
int[]	getDefaultTokens() Returns the default token a check is interested in.
int[]	getRequiredTokens() The tokens that this check must be registered for.
private boolean	isForwardReference(DetailAST fieldDef) Checks whether an identifier references a field which has been already defined in class.
void	leaveToken(DetailAST ast) Called after all the child nodes have been process.
private void	processConstructor(DetailAST ast) Processes constructor.
private void	processModifiers(DetailAST ast) Processes modifiers.
private boolean	processModifiersState(DetailAST modifierAst, DeclarationOrderCheck.ScopeState state) Process if given modifiers are appropriate in given state (STATE_STATIC_VARIABLE_DEF, STATE_INSTANCE_VARIABLE_DEF, (STATE_CTOR_DEF, STATE_METHOD_DEF), if it is it updates states where appropriate or logs violation.
private void	processModifiersSubState(DetailAST modifiersAst, DeclarationOrderCheck.ScopeState state, boolean isStateValid) Checks if given modifiers are valid in substate of given state(Scope), if it is it updates substate or else it logs violation.
void	setIgnoreConstructors(boolean ignoreConstructors) Setter to control whether to ignore constructors.
void	setIgnoreModifiers(boolean ignoreModifiers) Setter to control whether to ignore modifiers (fields, ...).
void	visitToken(DetailAST ast) Called to process a token.

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

clearViolations, destroy, finishTree, getFileContents, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, isCommentNodesRequired, log, log, log, setFileContents, setTabWidth, setTokens

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

finishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

configure, contextualize, getConfiguration, setupChild

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MSG_CONSTRUCTOR

public static final java.lang.String MSG_CONSTRUCTOR

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

MSG_STATIC

public static final java.lang.String MSG_STATIC

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

MSG_INSTANCE

public static final java.lang.String MSG_INSTANCE

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

MSG_ACCESS

public static final java.lang.String MSG_ACCESS

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

STATE_STATIC_VARIABLE_DEF

private static final int STATE_STATIC_VARIABLE_DEF

State for the VARIABLE_DEF.

See Also:

Constant Field Values

STATE_INSTANCE_VARIABLE_DEF

private static final int STATE_INSTANCE_VARIABLE_DEF

State for the VARIABLE_DEF.

See Also:

Constant Field Values

STATE_CTOR_DEF

private static final int STATE_CTOR_DEF

State for the CTOR_DEF.

See Also:

Constant Field Values

STATE_METHOD_DEF

private static final int STATE_METHOD_DEF

State for the METHOD_DEF.

See Also:

Constant Field Values

scopeStates

private java.util.Deque<DeclarationOrderCheck.ScopeState> scopeStates

List of Declaration States. This is necessary due to inner classes that have their own state.

classFieldNames

private java.util.Set<java.lang.String> classFieldNames

Set of all class field names.

ignoreConstructors

private boolean ignoreConstructors

Control whether to ignore constructors.

ignoreModifiers

private boolean ignoreModifiers

Control whether to ignore modifiers (fields, ...).

Constructor Detail

DeclarationOrderCheck

public DeclarationOrderCheck()

Method Detail

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:

TokenTypes

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:

TokenTypes

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:

TokenTypes

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

processConstructor

private void processConstructor(DetailAST ast)

Processes constructor.

Parameters:

ast - constructor AST.

processModifiers

private void processModifiers(DetailAST ast)

Processes modifiers.

Parameters:

ast - ast of Modifiers.

processModifiersState

private boolean processModifiersState(DetailAST modifierAst,
                                      DeclarationOrderCheck.ScopeState state)

Process if given modifiers are appropriate in given state (STATE_STATIC_VARIABLE_DEF, STATE_INSTANCE_VARIABLE_DEF, (STATE_CTOR_DEF, STATE_METHOD_DEF), if it is it updates states where appropriate or logs violation.

Parameters:

modifierAst - modifiers to process

state - current state

Returns:

true if modifierAst is valid in given state, false otherwise

processModifiersSubState

private void processModifiersSubState(DetailAST modifiersAst,
                                      DeclarationOrderCheck.ScopeState state,
                                      boolean isStateValid)

Checks if given modifiers are valid in substate of given state(Scope), if it is it updates substate or else it logs violation.

Parameters:

modifiersAst - modifiers to process

state - current state

isStateValid - is main state for given modifiers is valid

isForwardReference

private boolean isForwardReference(DetailAST fieldDef)

Checks whether an identifier references a field which has been already defined in class.

Parameters:

fieldDef - a field definition.

Returns:

true if an identifier references a field which has been already defined in class.

getAllTokensOfType

private static java.util.Set<DetailAST> getAllTokensOfType(DetailAST ast,
                                                           int tokenType)

Collects all tokens of specific type starting with the current ast node.

Parameters:

ast - ast node.

tokenType - token type.

Returns:

a set of all tokens of specific type starting with the current ast node.

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.