j2c-locale

This should be considered part of the internal support classes for the emulated java.util.Locale and should not be referenced in code. It contains some utilties that can be used to assist the authoring of annotation processors that generate code or data that is Locale aware, such as the emulation of java.text and others.

The classes included in this project should be considered internal, and this project should only be referenced as a dependency by j2cl-java-util-Locale.

Threeten backport

This project uses a shaded copy of the package org.threeten.bp.zone and a few other minimized support classes from the org.threeten.bp project.

Changes include:

• Very little code has actually been added except to assist testing and j2cl-java-util-TimeZone-annotation-processor.
• Most methods not required have not been deleted but have been commented out with slash slash comments. This results in value types such as LocalDateTime losing nearly all their beautiful conversion, math etc methods.
• A few methods have been made public to assist j2cl-java-util-TimeZone-annotation-processor & j2cl-java-util-TimeZone
• The inbuilt serialization support for all classes packaged here, has been kept but marked @GwtIncompatible and used to create the data used by the emulated java.util.TimeZone.
• Note the fork of threeten does not include the accompanying tests, which of course lowers the code coverage of this project significantly.

Click here for the official threeten license.

Maven usage

Logging (javac annotation processor argument)

Logging by all related annotation processors may be controlled by the walkingkooka.j2cl.locale.Logging annotation.

• NONE Nothing is written anywhere
• SLASH_SLASH_COMMENTS The generated java source file will contain slash slash comments holding the content.
• TXT_FILE A txt file will be created to match the class file for the generated *.java file plus the file extension DATA.txt.

The last two options will contain readable text of the value of the generated provider private final static String DATA field.

// en-001              language=en         country=001         variant=            script=             encoded=en-001,en,001
// en-150              language=en         country=150         variant=            script=             encoded=en-150,en,150
// en-AG               language=en         country=AG          variant=            script=             encoded=en-AG,en,AG
...
 public final static String DATA = preventInlining("106,en,en-001\\,en\...

Locale selection (javac annotation processor argument)

The locales must be selected by setting a annotation argument walkingkooka.java-util-Locale with a comma separated list of desired locales with trailing wildcard support.

Some examples values include.

• * All locales
• EN Only includes the EN locale without including EN-US or EN-GB.
• EN-* Includes all locales beginning with EN.
• EN-*,FR-* Include all English and French locales.

Maven annotation processor argument

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.8.0</version>
    <configuration>
        <source>9</source>
        <target>9</target>
        <compilerArgs>
            <arg>-Awalkingkooka.j2cl.java.util.Locale=EN-*</arg>
            <arg>-Awalkingkooka.j2cl.locale.Logging=TXT_FILE</arg>
        </compilerArgs>
        <showWarnings>true</showWarnings>
    </configuration>
</plugin>

The ShowWarning parameter is necessary as all annotation processor sub classes (shown below) print their parameters and the size of the DATA that holds their data encoded in String form.

Selecting many locales will result in the size of the DATA field being many times larger. This is particularly important as something such as java.time actually uses internally data for many classes:

• java.text.DateFormatSymbols
• java.text.DateFormat
• java.text.DecimalFormatSymbols
• java.text.DecimalFormat
• java.util.Locale
• java.text.Currency
• java.util.TimeZone

Related annotation processors

The following list, contains emulated java.util.Locale aware classes and their corresponding annotation processor. All within the list sub class walkingkooka.j2cl.locale.annotationprocessor.LocaleAwareAnnotationProcessor and use other support classes within this project.

• Currency supporting annotation processor
• DateFormatSymbols supporting annotation processor
• DecimalFormat supporting annotation processor
• DecimalFormatSymbols supporting annotation processor
• Locale supporting annotation processor
• TimeZone supporting annotation processor

Authoring annotation processors.

An abstract AnnotationProcessor is available with a few template methods which present the selected locales. It also handles some other housekeeping, relating to the annotation processor lifecycle.

Usage

The preferred way to use the plugin is to checkout the source

git clone git://github.com/mP1/j2cl-locale.git

and build and install with Maven.

mvn clean install

Contributions

Suggestions via the issue tracker, and pull requests are most welcomed.