# Documentation | PMD Source Code Analyzer
Keywords: Documentation, CommentContent, CommentRequired, CommentSize, UncommentedEmptyConstructor, UncommentedEmptyMethodBody

# Documentation

Rules that are related to code documentation.

## CommentContent

Since: PMD 5.0

Priority: Medium (3)

A rule for the politically correct… we don’t want to offend anyone.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.documentation.CommentContentRule

Example(s):

    //OMG, this is horrible, Bob is an idiot !!!

This rule has the following properties:

Name | Default Value | Description | Multivalued
--- | --- | --- | ---
caseSensitive | false | Case sensitive | no
disallowedTerms | idiot | jerk | Illegal terms or phrases | yes. Delimiter is ‘|’.

Use this rule with the default properties by just referencing it:

    <rule ref="category/java/documentation.xml/CommentContent" />

Use this rule and customize it:

    <rule ref="category/java/documentation.xml/CommentContent">
        <properties>
            <property name="caseSensitive" value="false" />
            <property name="disallowedTerms" value="idiot|jerk" />
        </properties>
    </rule>

## CommentRequired

Since: PMD 5.1

Priority: Medium (3)

Denotes whether javadoc (formal) comments are required (or unwanted) for specific language elements.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.documentation.CommentRequiredRule

Example(s):

    /**
    *
    *
    * @author Jon Doe
    */

This rule has the following properties:

Name | Default Value | Description | Multivalued
--- | --- | --- | ---
methodWithOverrideCommentRequirement | Ignored | Comments on @Override methods. Possible values: [Required, Ignored, Unwanted] | no
accessorCommentRequirement | Ignored | Comments on getters and setters". Possible values: [Required, Ignored, Unwanted] | no
classCommentRequirement | Required | Class comments. Possible values: [Required, Ignored, Unwanted] | no
headerCommentRequirement | Required | Deprecated Header comments. Please use the property "classCommentRequired" instead.. Possible values: [Required, Ignored, Unwanted] | no
fieldCommentRequirement | Required | Field comments. Possible values: [Required, Ignored, Unwanted] | no
publicMethodCommentRequirement | Required | Public method and constructor comments. Possible values: [Required, Ignored, Unwanted] | no
protectedMethodCommentRequirement | Required | Protected method constructor comments. Possible values: [Required, Ignored, Unwanted] | no
enumCommentRequirement | Required | Enum comments. Possible values: [Required, Ignored, Unwanted] | no
serialVersionUIDCommentRequired | Ignored | Serial version UID comments. Possible values: [Required, Ignored, Unwanted] | no
serialPersistentFieldsCommentRequired | Ignored | Serial persistent fields comments. Possible values: [Required, Ignored, Unwanted] | no

Use this rule with the default properties by just referencing it:

    <rule ref="category/java/documentation.xml/CommentRequired" />

Use this rule and customize it:

    <rule ref="category/java/documentation.xml/CommentRequired">
        <properties>
            <property name="methodWithOverrideCommentRequirement" value="Ignored" />
            <property name="accessorCommentRequirement" value="Ignored" />
            <property name="classCommentRequirement" value="Required" />
            <property name="fieldCommentRequirement" value="Required" />
            <property name="publicMethodCommentRequirement" value="Required" />
            <property name="protectedMethodCommentRequirement" value="Required" />
            <property name="enumCommentRequirement" value="Required" />
            <property name="serialVersionUIDCommentRequired" value="Ignored" />
            <property name="serialPersistentFieldsCommentRequired" value="Ignored" />
        </properties>
    </rule>

## CommentSize

Since: PMD 5.0

Priority: Medium (3)

Determines whether the dimensions of non-header comments found are within the specified limits.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.documentation.CommentSizeRule

Example(s):

    /**
    *
    *   too many lines!
    *
    *
    *
    *
    *
    *
    *
    *
    *
    *
    *
    *
    */

This rule has the following properties:

Name | Default Value | Description | Multivalued
--- | --- | --- | ---
maxLines | 6 | Maximum lines | no
maxLineLength | 80 | Maximum line length | no

Use this rule with the default properties by just referencing it:

    <rule ref="category/java/documentation.xml/CommentSize" />

Use this rule and customize it:

    <rule ref="category/java/documentation.xml/CommentSize">
        <properties>
            <property name="maxLines" value="6" />
            <property name="maxLineLength" value="80" />
        </properties>
    </rule>

## UncommentedEmptyConstructor

Since: PMD 3.4

Priority: Medium (3)

Uncommented Empty Constructor finds instances where a constructor does not contain statements, but there is no comment. By explicitly commenting empty constructors it is easier to distinguish between intentional (commented) and unintentional empty constructors.

This rule is defined by the following XPath expression:

    //ConstructorDeclaration[@Private= false()]
                            [@containsComment = false()]
                            [not(BlockStatement)]
                            [$ignoreExplicitConstructorInvocation = true() or not(ExplicitConstructorInvocation)]
                            [not(../Annotation/MarkerAnnotation/Name[
                                                                    pmd-java:typeIs('javax.inject.Inject')
                                                                 or pmd-java:typeIs('org.springframework.beans.factory.annotation.Autowired')
                                                                    ])]

Example(s):

    public Foo() {
      // This constructor is intentionally empty. Nothing special is needed here.
    }

This rule has the following properties:

Name | Default Value | Description | Multivalued
--- | --- | --- | ---
ignoreExplicitConstructorInvocation | false | Ignore explicit constructor invocation when deciding whether constructor is empty or not | no

Use this rule with the default properties by just referencing it:

    <rule ref="category/java/documentation.xml/UncommentedEmptyConstructor" />

Use this rule and customize it:

    <rule ref="category/java/documentation.xml/UncommentedEmptyConstructor">
        <properties>
            <property name="ignoreExplicitConstructorInvocation" value="false" />
        </properties>
    </rule>

## UncommentedEmptyMethodBody

Since: PMD 3.4

Priority: Medium (3)

Uncommented Empty Method Body finds instances where a method body does not contain statements, but there is no comment. By explicitly commenting empty method bodies it is easier to distinguish between intentional (commented) and unintentional empty methods.

This rule is defined by the following XPath expression:

    //MethodDeclaration/Block[count(BlockStatement) = 0 and @containsComment = false()]

Example(s):

    public void doSomething() {
    }

Use this rule by referencing it:

    <rule ref="category/java/documentation.xml/UncommentedEmptyMethodBody" />