PMD 7.3.0

Release date: 28-June-2024

About
User Documentation
Rule Reference
- Apex Rules
  - Index
  - Best Practices
  - Code Style
  - Design
  - Documentation
  - Error Prone
  - Performance
  - Security
- HTML Rules
  - Index
  - Best Practices
- Java Rules
- Java Server Pages Rules
  - Index
  - Best Practices
  - Code Style
  - Design
  - Error Prone
  - Security
- JavaScript Rules
- Kotlin Rules
- Maven POM Rules
  - Index
  - Error Prone
- Modelica Rules
  - Index
  - Best Practices
- PLSQL Rules
- Salesforce Visualforce Rules
  - Index
  - Security
- Scala Rules
  - Index
- Swift Rules
- Velocity Template Language (VTL) Rules
- WSDL Rules
  - Index
- XML Rules
- XSL Rules
Language-Specific Documentation
- Overview
- Language configuration
- Apex
- C/C++
- C#
- Coco
- Dart
- Fortran
- Gherkin
- Go
- HTML
- Java
- JavaScript / TypeScript
- JSP
- Julia
- Kotlin
- Lua
- Matlab
- Modelica
- Objective-C
- Perl
- PHP
- PLSQL
- Python
- Ruby
- Scala
- Swift
- T-SQL
- Visualforce
- Velocity Template Language (VTL)
- XML and XML dialects
Developer Documentation
Project documentation

» Code Style Edit on GitHub

Code Style

Rules which enforce a specific coding style.

Table of Contents

UseConcatOnce

Since: PMD 5.0

Priority: Medium (3)

The XPath concat() functions accepts as many arguments as required so you can have "concat($a,’b’,$c)" rather than "concat($a,concat(‘b’,$c)".

This rule is defined by the following XPath expression:

//node()[contains(substring-after(@select,'concat'),'concat')]

Example(s):

<xsl:variable name="var" select="concat("Welcome",concat("to you ",$name))"/>
<xsl:variable name="var" select="concat("Welcome","to you ",$name))">

Use this rule by referencing it:

<rule ref="category/xsl/codestyle.xml/UseConcatOnce" />