Excelsior JET Runtime Configurations - excelsior-oss/excelsior-jet-maven-plugin GitHub Wiki

The plugin enables you to configure the Excelsior JET Runtime via the <runtime> configuration section:

<runtime>
</runtime>

that may contain parameters described below.

• Runtime Flavor Selection
• Changing Default Runtime Location
• Compact Profiles
• Locales and Charsets
• Optional Components
• Disk Footprint Reduction
• Java Runtime Slim-Down Configurations

Excelsior JET VM comes with multiple implementations of the runtime system, optimized for different hardware configurations and application types.

To select a particular runtime flavor, use the <flavor> parameter of the <runtime> section. The flavors available in the Enterprise Edition and the Evaluation Package are desktop, server, and classic; other Excelsior JET products may not feature some of these.

For details, refer to the Excelsior JET User's Guide, Chapter "Application Considerations", section "Runtime Selection".

By default, Excelsior JET places its runtime files required for the generated executable to work in a folder named "rt" located next to that executable. You may change that default location with the <location> parameter of the <runtime> section.

Note: This functionality is only available in Excelsior JET 11.3 and above.

Java SE 8 defines three subsets of the standard Platform API called compact profiles. Excelsior JET enables you to deploy your application with one of those subsets.

To specify a particular profile, use the <profile> parameter of the <runtime> section. The valid values are auto (default), compact1, compact2, compact3, and full.

<profile>auto</profile> forces Excelsior JET to detect which parts of the Java SE Platform API are referenced by the application and select the smallest compact profile that includes them all, or the entire Platform API (full) if there is no such profile.

Note: This functionality is only available in Excelsior JET 11.3 and above.

Additional locales and character encoding sets that may potentially be in use in the regions where you distribute your application can be added to the package with the following configuration:

<runtime>
  <locales>
    <locale>Locale1</locale>
    <locale>Locale2</locale>
  </locales>
</runtime>

You may specify all as the value of <locale> to add all locales and charsets at once or none to not include any of them.

The available sets of locales and encodings are:

European, Indonesian, Malay, Hebrew, Arabic, Chinese, Japanese, Korean, Thai, Vietnamese, Hindi, Extended_Chinese, Extended_Japanese, Extended_Korean, Extended_Thai, Extended_IBM, Extended_Macintosh, Latin_3

By default, only the European locales are added.

To include optional JET Runtime components in the package, use the following configuration:

<runtime>
  <components>
    <component>optComponent1</component>
    <component>optComponent2</component>
  </components>
</runtime>

You may specify all as the value of <component> to add all components at once or none to not include any of them.

The available optional components are:

runtime_utilities, fonts, awt_natives, api_classes, jce, jdk_tools, accessibility (Windows only), javafx, javafx-webkit, javafx-swing, javafx-qtkit (macOS only), nashorn, cldr, dnsns, zipfs

Note: by default, the plugin automatically includes the optional components which the compiler detected as used when building the executable(s).

Excelsior JET is capable of reducing the disk footprint of an application compiled with the Global Optimizer enabled, by compressing the (supposedly) unused Java SE API classes.

To enable disk footprint reduction, add the following parameter to the <runtime> section:

<diskFootprintReduction>disk-footprint-reduction-mode</diskFootprintReduction>

The available modes are:

• none - disable compression
• medium - use a generic compression algorithm with minimal run time overheads and selective decompression
• high-memory - (32-bit only) compress all class files as a whole, resulting in a more significant disk footprint reduction compared to medium compression. The downside is that the entire bundle has to be decompressed to retrieve a single class, if it turns out to be required at run time. In the high-memory mode, the bundle is decompressed onto the heap and can be garbage collected later.
• high-disk - (32-bit only) compress as in the high-memory mode, decompress to the temp directory

The 32-bit versions of Excelsior JET feature Java Runtime Slim-Down, a unique Java application deployment model delivering a significant reduction of application download size and disk footprint.

The key idea is to select the components of the Java SE API that are not used by the application, and exclude them from the installation altogether. Such components are called detached. For example, if your application does not use any of Swing, AWT, CORBA or, say, JNDI API, Excelsior JET enables you to easily exclude from the main setup package the standard library classes implementing those APIs and the associated files, placing them in a separate detached package.

The detached package should be placed on a Web server so that the JET Runtime could download it if the deployed application attempts to use any of the detached components via JNI or the Reflection API.

Note: This functionality is deprecated since Excelsior JET 11.3 in favor of the newly added Compact Profiles feature, and will be removed in future versions.

To enable Java Runtime Slim-Down, copy and paste the following plugin configuration:

<runtime>
    <slimDown>
        <detachedBaseURL></detachedBaseURL>
    </slimDown>
</runtime>

and specify the base URL of the location where you plan to place the detached package, e.g. http://www.example.com/download/myapp/detached/.

By default, the plugin automatically detects which Java SE APIs your application does not use and detaches the respective JET Runtime components from the installation package. Alternatively, you may enforce detaching of particular components using the following parameter under the <slimDown> configuration section:

<detachComponents>comma-separated list of APIs</detachComponents>

Available detachable components: corba, management, xml, jndi, jdbc, awt/java2d, swing, jsound, rmi, jax-ws

At the end of the build process, the plugin places the detached package in the jet subdirectory of the Maven target build directory. You may configure its name with the <detachedPackage> parameter of the <slimDown> section (by default the name is ${project.build.finalName}.pkl).

Do not forget to upload the detached package to the location specified in <detachedBaseURL> above before deploying your application to end-users.

Note: Enabling Java Runtime Slim-Down automatically enables the Global Optimizer, so performing a Test Run is mandatory for Java Runtime Slim-Down as well.

Fixed issue: Java Runtime Slim-Down did not work with the excelsior-installer packaging type due to a bug in Excelsior JET. This issue is fixed in Excelsior JET 11 Maintenance Pack 2.