Ice Builder for Gradle

The Ice Builder for Gradle provides a Gradle plug-in named slice. This plug-in manages the compilation of Slice files to Java. It compiles your Slice files with slice2java, and it is also capable of generating Freeze maps and indices with slice2freezej.

An Ice installation with slice2java version 3.5.1 or higher is required.

Contents

• Build Instructions
• Using the slice Plug-In
  • Gradle Task
  • Project Layout
  • Convention Properties
  • Configuring Slice-to-Java Projects
    • java Properties
    • java Examples
  • Configuring Slice-to-FreezeJ Projects
    • freezej Properties
    • dict Block
      • dict Properties
      • dict Examples
    • index Block
      • index Properties
      • index Example
• When does the Plug-In Recompile Slice Files?

Build Instructions

To build the slice plug-in run:

./gradlew build

Using the slice Plug-in

Using the plugins DSL:

plugins {
  id "com.zeroc.gradle.ice-builder.slice" version "1.5.0"
}

Using legacy plugin application:

buildscript {
  repositories {
    maven {
      url "https://plugins.gradle.org/m2/"
    }
  }
  dependencies {
    classpath "gradle.plugin.com.zeroc.gradle.ice-builder:slice:1.5.0"
  }
}

apply plugin: "com.zeroc.gradle.ice-builder.slice"

It is important that the slice plug-in is applied after the java plug-in in order for task dependencies to be properly setup.

Gradle Task

The slice plug-in adds a task to your project, as shown below:

Task name	Type	Description
compileSlice	SliceTask	Generates Java source from Slice files.

The plug-in adds the following dependency to tasks added by the java plug-in:

Task name	Depends On
compileJava	compileSlice

On Android, it adds the following dependency to each build variant of project.android.libraryVariants, project.android.applicationVariants, and project.android.testVariants:

Task name	Depends On
javaCompiler	compileSlice

Project Layout

The plug-in assumes the following project layout:

Directory	Meaning
src/main/slice	Location of your project's Slice files.

This default layout can be changed with the property srcDir, described below.

Convention Properties

The slice plug-in defines the following convention properties:

Property name	Type	Default value	Description
iceHome	String	(see below)	The root directory of the Ice installation.
freezeHome	String	iceHome	The root directory of the Freeze installation.
output	File	buildDir/generated-src	The directory that contains the generated source files.
iceVersion	String		The Ice version returned by slice2java -v (read only).
sliceDir	String	(platform dependent)	The Ice Slice installation directory (read only).
slice2java	String	(platform dependent)	Full path of the slice2java compiler (read only).
slice2freezej	String	(platform dependent)	Full path of the slice2freezej compiler (read only).
cppPlatform	String	CPP_PLATFORM env variable, if set	See note below.
cppConfiguration	String	CPP_CONFIGURATION env variable, if set	See note below.
compat	Boolean	false if iceVersion >= 3.7, otherwise null	When iceVersion >= 3.7, adds --compat to the slice2java arguments.

If iceHome is not set, the plug-in will check the ICE_HOME environment variable to determine the location of the Ice installation. If ICE_HOME is not set either, the plug-in uses the following defaults on Linux and macOS:

OS	Default Ice Installation Directory
Linux	/usr
macOS	/usr/local

On Windows, when neither iceHome nor ICE_HOME are set, the builder queries the Windows registry to find Ice installations and selects the newest version.

You can set iceHome in your build script as shown below:

slice.iceHome = '/opt/Ice'

The slice plug-in usually finds the slice2java compiler in the bin directory of iceHome. On Windows, it prefers the following folders before falling back to bin:

• iceHome\cpp\bin\cppPlatform\cppConfiguration when using a source distribution and cpp\bin\cppPlatform\cppConfiguration folder exists (this corresponds to the layout of a source distribution for Ice version 3.7 or greater).

• iceHome\tools when not using a source distribution and the tools folder exists (this corresponds to the layout of a NuGet package).

The slice plug-in uses the same logic to locate the slice2freezej compiler within freezeHome.

Slice Plugin Methods

Method Name	Arugment(s)	Description
compareIceVersion	String	Compares iceVersion with given string. Returns -1, 0, or 1, depending on whether iceVersion is less than, equal to, or greater than given string, respectively.

Configuring Slice-to-Java Projects

Use the java block to configure the compilation of Slice files with slice2java. The java block can contain one or more source sets, each with its own set of flags for compiling Slice files. You can omit the source set name when you have a single set:

slice {
    java {
        ...
    }
}

Otherwise, the source sets must have unique names, for example:

slice {
    java {
        set1 {
            ...
        }
        set2 {
            ...
        }
    }
}

Each source set triggers a separate execution of the slice2java compiler.

java Properties

Each source set in the java block defines the following convention properties:

Property name	Type	Default value	Description
srcDir	File	src/main/slice	The Slice file source directory.
args	String	-	The arguments to slice2java.
files	FileCollection	-	The Slice files in this source set. Overrides srcDir.
include	Set	-	Slice include file search path.

Refer to the slice2java Command-Line Options for a description of the options you can provide through the args property.

Note: the slice directory of your Ice installation (${slice.iceHome}/slice) is automatically added to include by the plug-in.

java Examples

Compile all Slice files in src/main/slice with the --tie argument:

slice {
    java {
        args = "--tie"
    }
}

Compile a.ice with the argument --stream, and compile all Slice files in b without --stream. Both compilations add ${projectDir} to the Slice include search path:

slice {
    java {
        set1 {
            include = ["${projectDir}"]
            args = "--stream"
            files = [file("a.ice")]
        }
        set2 {
            include = ["${projectDir}"]
            files = fileTree(dir: "b", includes: ['**.ice'])
        }
    }
}

Configuring Slice-to-FreezeJ Projects

Use the freezej block to generate Freeze maps and indices with slice2freezej.

The plug-in currently supports a single unnamed source set within freezej:

slice {
  freezej {
      srcDir = "src/main/slice"
      ...
  }
}

freezej Properties

Each freezej block defines the following convention properties:

Property name	Type	Default value	Description
srcDir	File	src/main/slice	The Slice file source directory.
args	String	-	The arguments to slice2freezej.
files	FileCollection	-	The Slice files in this source set. Overrides srcDir.
include	Set	-	Slice include file search path.

Refer to the slice2freezej Command-Line Options for a description of the options you can provide through the args property.

Note: the slice directory of your Ice installation (${slice.iceHome}/slice) is automatically added to include by the plug-in.

dict Block

A dict block describes one ore more Freeze maps (also known as dictionaries) generated by slice2freezej. Each map in such a block must have a unique name.

slice {
    freezej {
        dict {
            Dict1 {
                ...
            }
            Dict2 {
                ...
            }
        }
    }
}

dict Properties

dict defines the following convention properties:

Property name	Type	Default value	Description
javaType	String	-	The name of the generated Java type.
key	String	-	The Slice type of the key.
value	String	-	The Slice type of the value.
index	List<Map<>>	-	Secondary index or indices.

The index is a list of maps. Valid entries in each map are as follows:

Key (String)	Value Type	Default value	Description
member	String	-	The name of a data member in the Freeze map value type.
caseSensitive	boolean	true	If member is a string, this specifies whether the comparison is case sensitive.

dict Examples

Given the following Slice definitions in Test.ice:

// Slice
module Test
{
    struct Foo
    {
        string s;
        Struct1 s1;
    }
}

Generate a Freeze map named StringFooMap that maps a string to the Slice type Test::Foo:

slice {
    freezej {
        files = [file("Test.ice")]
        dict {
            StringFooMap {
                javaType = "Test.StringFooMap"
                key = "string"
                value = "Test::Foo"
            }
        }
    }
}

Generate the same Freeze map, but this time with an index on the data member s of the Foo structure:

slice {
    freezej {
        files = [file("Test.ice")]
        dict {
            StringFooMap {
                javaType = "Test.StringFooMap"
                key = "string"
                value = "Test::Foo"
                index = [["member" : "s"]]
                // Example: case insensitive
                // index = [["member" : "s", "caseSensitive": false]]
                // Example: two indices.
                // index = [["member" : "s"], ['member': 's1']]
            }
        }
    }
}

Generate an int to string map, and create an index on the string value:

slice {
    freezej {
        dict {
            IntToStringMap {
                javaType = "Test.IntToStringMap"
                key = "int"
                value = "string"
                index = [[]] // list with one empty map to create an index on the full value
                // Same index but case insensitive:
                // index = [["caseSensitive": false]]
            }
        }
    }
}

index Block

An index block describes one ore more Freeze Evictor indices generated by slice2freezej. Each index must have a unique name.

slice {
    freezej {
        index {
            Index1 {
                ...
            }
            Index2 {
                ...
            }
        }
    }
}

index Properties

index defines the following convention properties:

Property name	Type	Default value	Description
javaType	String	-	The name of the generated Java type.
type	String	-	The Slice type of the type to be indexed.
member	String	-	The name of the data member in the type to index.
caseSensitive	boolean	true	If the member is a string, this specifies whether the comparison is case sensitive.

index Example

Given the following Slice type defined in Phonebook.ice:

// Slice
module Demo
{
    class Contact
    {
        string name;
        string address;
        string phone;
    }
}

Generate a Freeze Evictor index NameIndex for the data member name:

freezej {
    files = [file("PhoneBook.ice")]
    index {
        NameIndex {
            javaType = "NameIndex"
            type = "Demo::Contact"
            member = "name"
            caseSensitive = false
        }
    }
}

When does the Plug-in Recompile Slice Files?

Slice files will be recompiled if either of the following are true:

• This Slice file or a Slice file included directly or indirectly by this Slice file was updated after the last compilation of the Slice file through the plug-in.
• The options used to compile this Slice file have changed.

Removing a Slice file from a source set will trigger the removal of the corresponding generated .java files the next time the source set is built.