Rule (PMD Core 5.8.0 API)

All Superinterfaces:

PropertySource

All Known Subinterfaces:

CodeClimateRule, DFAGraphRule, StatisticalRule

All Known Implementing Classes:

AbstractDelegateRule, AbstractRule, MockRule, RuleReference, XPathRule
```
public interface Rule
extends PropertySource
```
This is the basic Rule interface for PMD rules.
Thread safety: PMD will create one instance of a rule per thread. The instances are not shared across different threads. However, a single rule instance is reused for analyzing multiple files.

Field Summary

Fields
Modifier and Type	Field and Description
`static StringProperty`	`VIOLATION_SUPPRESS_REGEX_DESCRIPTOR` The property descriptor to universally suppress violations with messages matching a regular expression.
`static StringProperty`	`VIOLATION_SUPPRESS_XPATH_DESCRIPTOR` Name of the property to universally suppress violations on nodes which match a given relative XPath expression.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`addExample(String example)` Add a single example for this Rule.
`void`	`addRuleChainVisit(Class<? extends Node> nodeClass)` Adds an AST node by class to be visited by the Rule on the RuleChain.
`void`	`addRuleChainVisit(String astNodeName)` Adds an AST node by name to be visited by the Rule on the RuleChain.
`void`	`apply(List<? extends Node> nodes, RuleContext ctx)` Apply this rule to the given collection of nodes, using the given context.
`void`	`end(RuleContext ctx)` End processing.
`String`	`getDescription()` Get the description of this Rule.
`List<String>`	`getExamples()` Get the list of examples for this Rule.
`String`	`getExternalInfoUrl()` Get a URL for external information about this Rule.
`Language`	`getLanguage()` Get the Language of this Rule.
`LanguageVersion`	`getMaximumLanguageVersion()` Get the maximum LanguageVersion to which this Rule applies.
`String`	`getMessage()` Get the message to show when this Rule identifies a violation.
`LanguageVersion`	`getMinimumLanguageVersion()` Get the minimum LanguageVersion to which this Rule applies.
`String`	`getName()` Get the name of this Rule.
`ParserOptions`	`getParserOptions()` Get the parser options for this Rule.
`RulePriority`	`getPriority()` Get the priority of this Rule.
`List<String>`	`getRuleChainVisits()` Gets the collection of AST node names visited by the Rule on the RuleChain.
`String`	`getRuleClass()` Get the implementation class of this Rule.
`String`	`getRuleSetName()` Get the name of the RuleSet containing this Rule.
`String`	`getSince()` Get the version of PMD in which this Rule was added.
`boolean`	`isDeprecated()` Gets whether this Rule is deprecated.
`void`	`setDeprecated(boolean deprecated)` Sets whether this Rule is deprecated.
`void`	`setDescription(String description)` Set the description of this Rule.
`void`	`setExternalInfoUrl(String externalInfoUrl)` Set a URL for external information about this Rule.
`void`	`setLanguage(Language language)` Set the Language of this Rule.
`void`	`setMaximumLanguageVersion(LanguageVersion maximumLanguageVersion)` Set the maximum LanguageVersion to which this Rule applies.
`void`	`setMessage(String message)` Set the message to show when this Rule identifies a violation.
`void`	`setMinimumLanguageVersion(LanguageVersion minimumLanguageVersion)` Set the minimum LanguageVersion to which this Rule applies.
`void`	`setName(String name)` Set the name of this Rule.
`void`	`setPriority(RulePriority priority)` Set the priority of this Rule.
`void`	`setRuleClass(String ruleClass)` Set the class of this Rule.
`void`	`setRuleSetName(String name)` Set the name of the RuleSet containing this Rule.
`void`	`setSince(String since)` Set the version of PMD in which this Rule was added.
`void`	`setUsesDFA()` Sets whether this Rule uses Data Flow Analysis.
`void`	`setUsesMetrics()` Sets whether this Rule uses Object-Oriented Metrics.
`void`	`setUsesTypeResolution()` Sets whether this Rule uses Type Resolution.
`void`	`start(RuleContext ctx)` Start processing.
`boolean`	`usesDFA()` Gets whether this Rule uses Data Flow Analysis.
`boolean`	`usesMetrics()` Gets whether this Rule uses Object-Oriented Metrics.
`boolean`	`usesRuleChain()` Gets whether this Rule uses the RuleChain.
`boolean`	`usesTypeResolution()` Gets whether this Rule uses Type Resolution.

Methods inherited from interface net.sourceforge.pmd.PropertySource
definePropertyDescriptor, dysfunctionReason, getPropertiesByPropertyDescriptor, getProperty, getPropertyDescriptor, getPropertyDescriptors, hasDescriptor, ignoredProperties, setProperty, useDefaultValueFor, usesDefaultValues

- Field Detail
  - VIOLATION_SUPPRESS_REGEX_DESCRIPTOR
```
static final StringProperty VIOLATION_SUPPRESS_REGEX_DESCRIPTOR
```
    The property descriptor to universally suppress violations with messages matching a regular expression.
  - VIOLATION_SUPPRESS_XPATH_DESCRIPTOR
```
static final StringProperty VIOLATION_SUPPRESS_XPATH_DESCRIPTOR
```
    Name of the property to universally suppress violations on nodes which match a given relative XPath expression.
- Method Detail
  - getLanguage
```
Language getLanguage()
```
    Get the Language of this Rule.
    
    Returns:
    the language
  - setLanguage
```
void setLanguage(Language language)
```
    Set the Language of this Rule.
    
    Parameters:
    language - the language
  - getMinimumLanguageVersion
```
LanguageVersion getMinimumLanguageVersion()
```
    Get the minimum LanguageVersion to which this Rule applies. If this value is null it indicates there is no minimum bound.
    
    Returns:
    the minimum language version
  - setMinimumLanguageVersion
```
void setMinimumLanguageVersion(LanguageVersion minimumLanguageVersion)
```
    Set the minimum LanguageVersion to which this Rule applies.
    
    Parameters:
    minimumLanguageVersion - the minimum language version
  - getMaximumLanguageVersion
```
LanguageVersion getMaximumLanguageVersion()
```
    Get the maximum LanguageVersion to which this Rule applies. If this value is null it indicates there is no maximum bound.
    
    Returns:
    the maximum language version
  - setMaximumLanguageVersion
```
void setMaximumLanguageVersion(LanguageVersion maximumLanguageVersion)
```
    Set the maximum LanguageVersion to which this Rule applies.
    
    Parameters:
    maximumLanguageVersion - the maximum language version
  - isDeprecated
```
boolean isDeprecated()
```
    Gets whether this Rule is deprecated. A deprecated Rule is one which:
    - is scheduled for removal in a future version of PMD
    - or, has been removed and replaced with a non-functioning place-holder and will be completely removed in a future version of PMD
    - or, has been renamed/moved and the old name will be completely removed in a future version of PMD
    Returns:
    true if this rule is deprecated
  - setDeprecated
```
void setDeprecated(boolean deprecated)
```
    Sets whether this Rule is deprecated.
    
    Parameters:
    deprecated - whether this rule is deprecated
  - getName
```
String getName()
```
    Get the name of this Rule.
    
    Returns:
    the name
  - setName
```
void setName(String name)
```
    Set the name of this Rule.
    
    Parameters:
    name - the name
  - getSince
```
String getSince()
```
    Get the version of PMD in which this Rule was added. Return null if not applicable.
    
    Returns:
    version of PMD since when this rule was added
  - setSince
```
void setSince(String since)
```
    Set the version of PMD in which this Rule was added.
    
    Parameters:
    since - the version of PMD since when this rule was added
  - getRuleClass
```
String getRuleClass()
```
    Get the implementation class of this Rule.
    
    Returns:
    the implementation class name of this rule.
  - setRuleClass
```
void setRuleClass(String ruleClass)
```
    Set the class of this Rule.
    
    Parameters:
    ruleClass - the class name of this rule.
  - getRuleSetName
```
String getRuleSetName()
```
    Get the name of the RuleSet containing this Rule.
    
    Returns:
    the name of th ruleset containing this rule.
    See Also:
    RuleSet
  - setRuleSetName
```
void setRuleSetName(String name)
```
    Set the name of the RuleSet containing this Rule.
    
    Parameters:
    name - the name of the ruleset containing this rule.
    See Also:
    RuleSet
  - getMessage
```
String getMessage()
```
    Get the message to show when this Rule identifies a violation.
    
    Returns:
    the message to show for a violation.
  - setMessage
```
void setMessage(String message)
```
    Set the message to show when this Rule identifies a violation.
    
    Parameters:
    message - the message to show for a violation.
  - getDescription
```
String getDescription()
```
    Get the description of this Rule.
    
    Returns:
    the description
  - setDescription
```
void setDescription(String description)
```
    Set the description of this Rule.
    
    Parameters:
    description - the description
  - getExamples
```
List<String> getExamples()
```
    Get the list of examples for this Rule.
    
    Returns:
    the list of examples for this rule.
  - addExample
```
void addExample(String example)
```
    Add a single example for this Rule.
    
    Parameters:
    example - a single example to add
  - getExternalInfoUrl
```
String getExternalInfoUrl()
```
    Get a URL for external information about this Rule.
    
    Returns:
    the URL for external information about this rule.
  - setExternalInfoUrl
```
void setExternalInfoUrl(String externalInfoUrl)
```
    Set a URL for external information about this Rule.
    
    Parameters:
    externalInfoUrl - the URL for external information about this rule.
  - getPriority
```
RulePriority getPriority()
```
    Get the priority of this Rule.
    
    Returns:
    the priority
  - setPriority
```
void setPriority(RulePriority priority)
```
    Set the priority of this Rule.
    
    Parameters:
    priority - the priority
  - getParserOptions
```
ParserOptions getParserOptions()
```
    Get the parser options for this Rule. Parser options are used to configure the Parser to create an AST in the form the Rule is expecting. Because ParserOptions are mutable, a Rule should return a new instance on each call.
    
    Returns:
    the parser options
  - setUsesDFA
```
void setUsesDFA()
```
    Sets whether this Rule uses Data Flow Analysis.
  - usesDFA
```
boolean usesDFA()
```
    Gets whether this Rule uses Data Flow Analysis.
    
    Returns:
    true if Data Flow Analysis is used.
  - setUsesTypeResolution
```
void setUsesTypeResolution()
```
    Sets whether this Rule uses Type Resolution.
  - usesTypeResolution
```
boolean usesTypeResolution()
```
    Gets whether this Rule uses Type Resolution.
    
    Returns:
    true if Type Resolution is used.
  - setUsesMetrics
```
void setUsesMetrics()
```
    Sets whether this Rule uses Object-Oriented Metrics.
  - usesMetrics
```
boolean usesMetrics()
```
    Gets whether this Rule uses Object-Oriented Metrics.
    
    Returns:
    true if the Metrics Framework is used.
  - usesRuleChain
```
boolean usesRuleChain()
```
    Gets whether this Rule uses the RuleChain.
    
    Returns:
    true if RuleChain is used.
  - getRuleChainVisits
```
List<String> getRuleChainVisits()
```
    Gets the collection of AST node names visited by the Rule on the RuleChain.
    
    Returns:
    the list of AST node names
  - addRuleChainVisit
```
void addRuleChainVisit(Class<? extends Node> nodeClass)
```
    Adds an AST node by class to be visited by the Rule on the RuleChain.
    
    Parameters:
    nodeClass - the AST node to add to the RuleChain visit list
  - addRuleChainVisit
```
void addRuleChainVisit(String astNodeName)
```
    Adds an AST node by name to be visited by the Rule on the RuleChain.
    
    Parameters:
    astNodeName - the AST node to add to the RuleChain visit list as string
  - start
```
void start(RuleContext ctx)
```
    Start processing. Called once, before apply() is first called.
    
    Parameters:
    ctx - the rule context
  - apply
```
void apply(List<? extends Node> nodes,
         RuleContext ctx)
```
    Apply this rule to the given collection of nodes, using the given context.
    
    Parameters:
    nodes - the nodes
    ctx - the rule context
  - end
```
void end(RuleContext ctx)
```
    End processing. Called once, after apply() is last called.
    
    Parameters:
    ctx - the rule context

Interface Rule

Field Summary

Method Summary

Methods inherited from interface net.sourceforge.pmd.PropertySource

Field Detail

VIOLATION_SUPPRESS_REGEX_DESCRIPTOR

VIOLATION_SUPPRESS_XPATH_DESCRIPTOR

Method Detail

getLanguage

setLanguage

getMinimumLanguageVersion

setMinimumLanguageVersion

getMaximumLanguageVersion

setMaximumLanguageVersion

isDeprecated

setDeprecated

getName

setName

getSince

setSince

getRuleClass

setRuleClass

getRuleSetName

setRuleSetName

getMessage

setMessage

getDescription

setDescription

getExamples

addExample

getExternalInfoUrl

setExternalInfoUrl

getPriority

setPriority

getParserOptions

setUsesDFA

usesDFA

setUsesTypeResolution

usesTypeResolution

setUsesMetrics

usesMetrics

usesRuleChain

getRuleChainVisits

addRuleChainVisit

addRuleChainVisit

start

apply

end