pmd/docs/_data/xpath_funs.yml

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# This file describes custom XPath functions per language
# This is rendered using _includes/custom/xpath_fun_doc.html
aliases:
- &qname_param
name: javaQualifiedName
type: "xs:string"
description: "The qualified name of a Java class, possibly with pairs of brackets to indicate an array type.
Can also be a primitive type name."
- &node_param
name: element
type: "xs:element"
description: "Any element node"
- &needs_typenode "The context node must be a {% jdoc jast::TypeNode %}"
- &coord_fun_note |
The function is not context-dependent, but takes a node as its first parameter.
- &needs_node_ctx "The requires the context node to be an element"
langs:
- name: "All languages"
ns: "pmd"
header: "Functions available to all languages are in the namespace `pmd`."
funs:
- name: fileName
returnType: "xs:string"
shortDescription: "Returns the simple name of the current file"
description: |
Returns the current simple file name, without path but including the extension.
This can be used to write rules that check file naming conventions.
since: 6.38.0
notes: *needs_node_ctx
examples:
- code: "//b[pmd:fileName() = 'Foo.xml']"
outcome: "Matches any `<b>` tags in files called `Foo.xml`."
- name: startLine
returnType: "xs:int"
parameters:
- *node_param
shortDescription: "Returns the start line of the given node"
description: |
Returns the line where the node starts in the source file.
Line numbers are 1-based.
since: 6.44.0
notes: *coord_fun_note
examples:
- code: "//b[pmd:startLine(.) > 5]"
outcome: "Matches any `<b>` node which starts after the fifth line."
- name: endLine
returnType: "xs:int"
parameters:
- *node_param
shortDescription: "Returns the end line of the given node"
description: |
Returns the line where the node ends in the source file.
Line numbers are 1-based.
since: 6.44.0
notes: *coord_fun_note
examples:
- code: "//b[pmd:endLine(.) == pmd:startLine(.)]"
outcome: "Matches any `<b>` node which doesn't span more than one line."
- name: startColumn
returnType: "xs:int"
parameters:
- *node_param
shortDescription: "Returns the start column of the given node (inclusive)"
description: |
Returns the column number where the node starts in the source file.
Column numbers are 1-based. The start column is inclusive.
since: 6.44.0
notes: *coord_fun_note
examples:
- code: "//b[pmd:startColumn(.) = 1]"
outcome: "Matches any `<b>` node which starts on the first column of a line"
- name: endColumn
returnType: "xs:int"
parameters:
- *node_param
shortDescription: "Returns the end column of the given node (exclusive)"
description: |
Returns the column number where the node ends in the source file.
Column numbers are 1-based. The end column is exclusive.
since: 6.44.0
notes: *coord_fun_note
examples:
- code: "//b[pmd:startLine(.) = pmd:endLine(.) and pmd:endColumn(.) - pmd:startColumn(.) = 1]"
outcome: "Matches any `<b>` node which spans exactly one character"
- name: "Java"
ns: "pmd-java"
funs:
- name: nodeIs
returnType: "xs:boolean"
shortDescription: "Tests the runtime type of the node instance"
description: "Returns true if the runtime type of the AST node is a subtype of the given class.
Contrary to typeIs, this tests the type of the AST node.
For example, the AST node for a literal (e.g. `5d`) has type ASTNumericLiteral,
and this function will ignore the static type of the expression (double)"
parameters:
- name: nodeClassName
type: "xs:string"
description: "Simple name of a class or interface in package {% jdoc_package :jast %}, without the 'AST' prefix"
examples:
- code: '//*[pmd-java:nodeIs("Expression")]'
outcome: "Matches all nodes that implement {% jdoc jast::ASTExpression %}"
- code: '//*[pmd-java:nodeIs("TypeDeclaration")]'
outcome: "Matches all nodes that implement {% jdoc jast::ASTTypeDeclaration %}"
- code: '//*[pmd-java:nodeIs("Foo")]'
outcome: "Runtime error, there's no class ASTFoo in the package"
- name: typeIs
returnType: "xs:boolean"
shortDescription: "Tests a node's static type"
description: "Returns true if the context node's static Java type is a subtype of the given type.
This tests for the resolved type of the Java construct, not the type of the AST node.
For example, the AST node for a literal (e.g. `5d`) has type ASTNumericLiteral, however this
function will compare the type of the literal (eg here, `double`) against the argument."
notes: *needs_typenode
parameters:
- *qname_param
examples:
- code: '//FormalParameter[pmd-java:typeIs("java.lang.String[]")]'
outcome: "Matches formal parameters of type `String[]` (including vararg parameters)"
- code: '//VariableId[pmd-java:typeIs("java.lang.List")]'
outcome: "Matches variable declarators of type `List` or any of its subtypes (including e.g. `ArrayList`)"
- name: typeIsExactly
returnType: "xs:boolean"
shortDescription: "Tests a node's static type, ignoring subtypes"
description: "Returns true if the context node's static type is exactly the given type.
In particular, returns false if the context node's type is
a subtype of the given type."
notes: *needs_typenode
parameters:
- *qname_param
examples:
- code: '//VariableId[pmd-java:typeIsExactly("java.lang.List")]'
outcome: "Matches variable declarators of type `List` (but not e.g. `ArrayList`)"
- name: metric
returnType: "xs:decimal?"
shortDescription: "Computes and returns the value of a metric"
description:
Returns the value of the metric as evaluated on the context node.
If the metric cannot be computed on that node, returns an empty sequence
(which is falsy).
parameters:
- name: "metricKey"
type: "xs:string"
description: "The name of a metric in {% jdoc jmx::JavaMetrics %} (or an alias thereof)."
examples:
- code: "//ClassDeclaration[metric('NCSS') > 200]"
outcome: ""
- code: "//MethodDeclaration[metric('CYCLO') > 10 and metric('NCSS') > 20]"
outcome: ""
- code: "//TypeParameter[metric('idontexist') > 50]"
outcome: "Error: no such metric"
- name: hasAnnotation
returnType: "xs:boolean"
shortDescription: "Tests whether an annotation is present on the node"
description: "Returns true if the node has an annotation with the given qualified name"
notes: "The context node must be an {% jdoc jast::Annotatable %}, otherwise this returns false"
parameters:
- name: annotationClassName
type: "xs:string"
description: "Canonical name of an annotation type"
examples:
- code: '//MethodDeclaration[pmd-java:hasAnnotation("java.lang.Override")]'
outcome: "Matches all method declarations that are annotated with @Override"
- name: modifiers
returnType: "xs:string*"
shortDescription: "Produce the effective modifiers of a node"
description: >-
Returns a sequence of the effective modifiers of a node as strings.
This is documented on {% jdoc jast::ASTModifierList#getEffectiveModifiers() %}.
notes: "The context node must be an {% jdoc jast::ModifierOwner %}, otherwise this returns an empty sequence"
parameters:
examples:
- code: '//MethodDeclaration[pmd-java:modifiers() = "native"]'
outcome: "Matches native method declarations"
- code: '//MethodDeclaration[pmd-java:modifiers() = ("native", "static")]'
outcome: >-
Matches method declarations that have a 'native' OR a 'static' modifier.
This may be counter-intuitive.
- code: '//MethodDeclaration[pmd-java:modifiers() = "public"]'
outcome: >-
Matches method declarations that have a 'public' modifier, explicit or implicit.
For example, this would match methods in interfaces, which implicitly have the
modifier. Use the `explicitModifiers` function if you don't want the implicit part.
Also note that `@Visibility = 'public'` is a better use of the API, in this particular
instance.
- name: explicitModifiers
returnType: "xs:string*"
shortDescription: "Produce the explicit modifiers of a node"
description: >-
Returns a sequence of the explicit modifiers of a node as strings.
This is documented on {% jdoc jast::ASTModifierList#getExplicitModifiers() %}.
notes: "The context node must be an {% jdoc jast::ModifierOwner %}, otherwise this returns an empty sequence"
parameters:
examples:
- code: '//MethodDeclaration[pmd-java:explicitModifiers() = "public"]'
outcome: "Matches method declarations that have an explicit 'public' modifier."
- name: matchesSig
returnType: "xs:boolean"
shortDescription: "Matches the signature called by a method or constructor call"
description: >-
Uses an {% jdoc java::lang.java.types.TypeTestUtil.InvocationMatcher %} to test
the method signature called by the context node. The format of the parameter is
described on that class.
notes: "The context node must be an {% jdoc jast::InvocationNode %}, otherwise this returns false"
parameters:
- name: "sig"
type: "xs:string"
description: "A signature, in the format described on {% jdoc java::lang.java.types.TypeTestUtil.InvocationMatcher %}"
examples:
- code: '//MethodCall[pmd-java:matchesSig("_#equals(java.lang.Object)")]'
outcome: "Matches calls to the method `equals` on any receiver type"
- code: '//MethodCall[pmd-java:matchesSig("java.lang.Enum#equals(java.lang.Object)")]'
outcome: "Matches calls to the method `equals` on receiver that is a subtype of Enum"
- code: '//MethodCall[pmd-java:matchesSig("java.lang.String#toString()")]'
outcome: "Matches calls to the method `toString` on String receivers"
- code: '//MethodCall[pmd-java:matchesSig("_#_(int,int)")]'
outcome: "Matches calls to any method with 2 `int` parameters (!= argument)"
- code: '//ConstructorCall[pmd-java:matchesSig("java.util.ArrayList#new(int)")]'
outcome: "Matches constructors calls of ArrayList with a single int parameter"