Class OrderedPropertiesCheck

All Implemented Interfaces:
Configurable, Contextualizable, FileSetCheck

public class OrderedPropertiesCheck extends AbstractFileSetCheck

Detects if keys in properties files are in correct order.

Rationale: Sorted properties make it easy for people to find required properties by name in file. It makes merges more easy. While there are no problems at runtime. This check is valuable only on files with string resources where order of lines does not matter at all, but this can be improved. E.g.: checkstyle/src/main/resources/com/puppycrawl/tools/checkstyle/messages.properties You may suppress warnings of this check for files that have an logical structure like build files or log4j configuration files. See SuppressionFilter. <suppress checks="OrderedProperties" files="log4j.properties|ResourceBundle/Bug.*.properties|logging.properties"/>

Known limitation: The key should not contain a newline. The string compare will work, but not the line number reporting.

  • Property fileExtensions - Specify file type extension of the files to check. Type is java.lang.String[]. Default value is .properties.

To configure the check:

<module name="OrderedProperties"/>

Example properties file:

 A =65
 a =97
 key =107 than nothing
 key.sub =k is 107 and dot is 46
 key.png =value - violation
 

We check order of key's only. Here we would like to use an Locale independent order mechanism, an binary order. The order is case insensitive and ascending.

  • The capital A is on 65 and the lowercase a is on position 97 on the ascii table.
  • Key and key.sub are in correct order here, because only keys are relevant. Therefore on line 5 you have only "key" an nothing behind. On line 6 you have "key." The dot is on position 46 which is higher than nothing. key.png will reported as violation because "png" comes before "sub".

Parent is com.puppycrawl.tools.checkstyle.Checker

Violation Message Keys:

  • properties.notSorted.property
  • unable.open.cause
Since:
8.22
  • Field Details

    • MSG_KEY

      public static final String MSG_KEY
      Localization key for check violation.
      See Also:
    • MSG_IO_EXCEPTION_KEY

      public static final String MSG_IO_EXCEPTION_KEY
      Localization key for IO exception occurred on file open.
      See Also:
  • Constructor Details

    • OrderedPropertiesCheck

      public OrderedPropertiesCheck()
      Construct the check with default values.
  • Method Details

    • processFiltered

      protected void processFiltered(File file, FileText fileText)
      Processes the file and check order.
      Specified by:
      processFiltered in class AbstractFileSetCheck
      Parameters:
      file - the file to be processed
      fileText - the contents of the file.