Ice Builder for Ant

The Ice Builder for Ant provides two ant tasks, slice2java and slice2jfreezej, that automate the execution of the Slice-to-Java and Slice-to-FreezeJ compilers.

Contents

• Install Instructions
  • Download
  • Build From Source
• Execution Environment
• slice2java Task
  • Parameters
  • Nested Elements
  • Using the Task
• slice2freezej Task
  • Parameters
  • Nested Elements
  • Using the Task
• When do the slice2java and slice2freezej tasks recompile Slice files?

Install Instructions

Download

The Ice Builder for Ant is available from the Maven Central repository with groupId:com.zeroc and artifactId:ant-ice. Refer to your build systems' documentation for adding additional repositories.

Build From Source

Use the following command to build the Ice Builder for Ant jar file (ant-ice-4.1.0.jar):

  $ ./gradlew build

Execution Environment

The slice2java and slice2freezej tasks must be able to locate and spawn the slice2java and slice2freezej executables. You can specify the directory of your Ice installation by defining the ice.home ant property or the ICE_HOME environment variable, in which case the task assumes that the Slice compiler's executable is located in the bin subdirectory of the specified installation directory. For example, if ICE_HOME is set to /opt/Ice on Linux, the task assumes that the executable path name is /opt/Ice/bin/slice2java or /opt/Ice/bin/slice2freezej. Furthermore, the tasks also configure their shared library search path (if necessary for your platform) to ensure the executable can resolve its library dependencies.

If both ice.home and ICE_HOME are defined, ice.home takes precedence. If neither are defined, the task assumes that the executables can be found in your PATH and that your shared library search path is configured correctly.

Finally, you can use a task parameter to specify the full path name of the Slice compiler. Again, the tasks assume that your shared library search path is configured correctly.

slice2java Task

Parameters

The task supports the parameters listed in the following table:

Attribute	Description	Required
checksum	Specifies the name of a class to contain the Slice checksums.	No
dependencyfile	Specifies an alternate name for the .depend file. If you specify a relative filename, it is relative to ant's current working directory. If not specified, the task uses the name .depend by default. If you do not define this attribute and outputdir is defined, the task creates the .depend file in the designated output directory (see outputdir).	No
ice	Instructs the Slice compiler to permit symbols that have a reserved prefix such as Ice and Glacier2.	No
outputdir	Specifies the directory in which the Slice compiler generates Java source files. If not specified, the task uses ant's current working directory.	No
stream	Indicates whether to generate streaming support. If not specified, streaming support is not generated.	No
tie	Indicates whether to generate tie classes. If not specified, tie classes are not generated.	No
compat	Indicates whether to use the Java Compat mapping. If not specified, the newer mapping will be used.	No
translator	Specifies the path name of the Slice compiler. If not specified, the task locates the Slice compiler in its execution environment.	No

For the flag parameters (ice, stream, and tie), valid positive values are on, true, or yes; negative values are off, false, or no.

Nested Elements

Several Slice compiler options must be defined as nested elements of the task:

• define

  Defines a preprocessor macro. The element supports the attributes name and (optionally) value, as shown below:

  <define name="FOO">
  <define name="BAR" value="5">

  These definitions are equivalent to the command-line options -DFOO and -DBAR=5, respectively.

• fileset

  Specifies the set of Slice files to be compiled. Refer to the ant documentation of its FileSet type for more information.

• includepath

  Specifies the include file search path for Slice files. In ant terminology, includepath is a path-like structure. Refer to the ant documentation of its Path type for more information.

• meta

  Defines a global metadata directive in each Slice file as well as in each included Slice file. The element supports name and value attributes.

Using the Task

Define the following taskdef element in your project's build file to enable the task:

<taskdef name="slice2java" classname="Slice2JavaTask"/>

This configuration assumes that ant-ice-4.1.0.jar is already present in ant's class path. Alternatively, you can specify the JAR explicitly as follows:

<taskdef name="slice2java" classpath="/opt/Ice/lib/ant-ice-4.1.0.jar"
    classname="Slice2JavaTask"/>

Once activated, you can invoke the task to translate your Slice files. The example shown below is a simplified version of the ant project for the hello demo:

<target name="generate" depends="init">
    <mkdir dir="generated"/>
    <slice2java outputdir="generated">
        <fileset dir="." includes="Hello.ice"/>
    </slice2java>
</target>

<target name="compile" depends="generate">
    <mkdir dir="classes"/>
    <javac srcdir=".:generated" destdir="classes">
        <exclude name="generated/**"/>
        ...
    </javac>
</target>

<target name="all" depends="compile"/>

<target name="clean">
    <delete dir="generated"/>
    <delete dir="classes"/>
</target>

This project demonstrates some practices that we encourage you to adopt in your own projects. First, it is helpful to keep the source files generated by the Slice compiler separate from your application's source files by dedicating an output directory for the exclusive use of the Slice compiler. Doing so helps to minimize confusion and makes it easier to configure a source-code management system to ignore generated files.

Next, we also recommend that you include a clean target in your ant project that removes this output directory. Assuming that the dependency file (.depend) is also stored in this directory, removing the output directory is an efficient way to clean up your project's source tree and guarantees that all of your Slice files are recompiled in the next build.

Finally, after seeing the exclude element in the invocation of javac you might infer that the generated code was not being compiled, but the presence of the output directory in the srcdir attribute ensures that the generated code is included in the build. The purpose of the exclude element is to prevent ant from including the generated files twice in its target list.

slice2freezej Task

Parameters

Attribute	Description	Required
dependencyfile	Specifies an alternate name for the .depend file. If you specify a relative filename, it is relative to ant's current working directory. If not specified, the task uses the name .depend by default. If you do not define this attribute and outputdir is defined, the task creates the .depend file in the designated output directory (see outputdir).	No
ice	Instructs the Slice compiler to permit symbols that have a reserved prefix such as Ice or Glacier2.	No
outputdir	Specifies the directory in which the Slice compiler generates Java source files. If not specified, the task uses ant's current working directory.	No
translator	Specifies the path name of the Slice compiler. If not specified, the task locates the Slice compiler in its execution environment.	No

Nested Elements

Several Slice compiler options must be defined as nested elements of the task:

• define

  Defines a preprocessor macro. The element supports the attributes name and (optionally) value, as shown below:

  <define name="FOO">
  <define name="BAR" value="5">

  These definitions are equivalent to the command-line options -DFOO and -DBAR=5, respectively.

• dict

  Generates a Freeze map. This element is equivalent to the --dict command line option and supports three attributes: name, key, and value.

• dictindex

  Generates an index for a Freeze map. This element is equivalent to the --dict-index command line option and supports three attributes: name, member, and casesensitive.

• fileset

  Specifies the set of Slice files to be compiled. Refer to the ant documentation of its FileSet type for more information.

• includepath

  Specifies the include file search path for Slice files. In ant terminology, includepath is a path-like structure. Refer to the ant documentation of its Path type for more information.

• index

  Generates an index for a Freeze evictor. This element is equivalent to the --index command line option and supports four attributes: name, type, member, and casesensitive.

• meta

  Defines a global metadata directive in each Slice file as well as in each included Slice file. The element supports the attributes name and value.

Using the Task

Define the following taskdef element in your project's build file to enable the task:

<taskdef name="slice2freezej" classname="Slice2FreezeJTask"/>

This configuration assumes that ant-ice-4.1.0.jar is already present in ant's class path. Alternatively, you can specify the JAR explicitly as follows:

<taskdef name="slice2freezej" classpath="/opt/Ice/lib/ant-ice-4.1.0.jar"
    classname="Slice2FreezeJTask"/>

Once activated, you can invoke the task to translate your Slice files. The example shown below is a simplified version of the ant project for the library demo:

<target name="generate" depends="init">
    <mkdir dir="generated"/>
    <slice2java outputdir="generated">
        <fileset dir="." includes="Library.ice"/>
    </slice2java>
    <slice2freezej ice="on" outputdir="generated">
        <fileset dir="/opt/Ice/slice/Ice" includes="BuiltinSequences.ice"/>
        <fileset dir="." includes="Library.ice"/>
        <dict name="StringIsbnSeqDict" key="string" value="Ice::StringSeq"/>
    </slice2freezej>
</target>

This invocation of the slicefreezej task enables the ice option because the generated Freeze map relies on a type that is defined in the Ice module and therefore loads the Slice file BuiltinSequences.ice directly.

When do the slice2java and slice2freezej tasks recompile Slice files?

The tasks minimize recompilation by keeping track of dependencies between Slice files. For example, A.ice depends on B.ice and C.ice when A.ice includes B.ice and B.ice includes C.ice. Each task stores this information in a file named .depend in the output directory and updates these dependencies after each compilation. (You can also specify a different name for this file using a task parameter.)

Note that the tasks do not keep track of the Java source files generated from the Slices files. Consequently, removing the generated Java source files does not trigger a recompilation of the Slice file. In fact, a task compiles a Slice file only when any of the following conditions are true:

• The .depend file does not exist.
• The .depend file does not contain any information for this Slice file.
• The modification time of this Slice file is later than the modification time of the .depend file.
• This Slice file includes another Slice file that is eligible for (re)compilation.

The simplest way to force the tasks to recompile all of your Slice files is to remove the .depend file.