Class StringLiteralsConcatenationCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.AbstractAutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.qulice.checkstyle.StringLiteralsConcatenationCheck
All Implemented Interfaces:
com.puppycrawl.tools.checkstyle.api.Configurable, com.puppycrawl.tools.checkstyle.api.Contextualizable

public final class StringLiteralsConcatenationCheck extends com.puppycrawl.tools.checkstyle.api.AbstractCheck
Checks for not using concatenation of string literals in any form.

The following constructs are prohibited:

 String a = "done in " + time + " seconds";
 System.out.println("File not found: " + file);
 x += "done";
 

You should avoid string concatenation at all cost. Why? There are two reasons: readability of the code and translateability. First of all it's difficult to understand how the text will look after concatenation, especially if the text is long and there are more than a few + operators. Second, you won't be able to translate your text to other languages later, if you don't have solid string literals.

There are two alternatives to concatenation: StringBuilder and String.format(String,Object[]).

Since:
0.3
  • Nested Class Summary

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

    com.puppycrawl.tools.checkstyle.AbstractAutomaticBean.OutputStreamOptions
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
     
    int[]
     
    int[]
     
    void
    visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST ast)
     

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

    beginTree, clearViolations, destroy, finishTree, getFileContents, getFilePath, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, isCommentNodesRequired, leaveToken, 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.AbstractAutomaticBean

    configure, contextualize, getConfiguration, setupChild

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • StringLiteralsConcatenationCheck

      public StringLiteralsConcatenationCheck()
  • Method Details

    • getDefaultTokens

      public int[] getDefaultTokens()
      Specified by:
      getDefaultTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
    • getAcceptableTokens

      public int[] getAcceptableTokens()
      Specified by:
      getAcceptableTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
    • getRequiredTokens

      public int[] getRequiredTokens()
      Specified by:
      getRequiredTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
    • visitToken

      public void visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST ast)
      Overrides:
      visitToken in class com.puppycrawl.tools.checkstyle.api.AbstractCheck