A compiler plugin simplifies writing and maintaining data model classes for public APIs by auto-generating `toString`, `equals`, and `hashCode` functions, with optional array content-based checks.
Poko is a Kotlin compiler plugin that makes writing and maintaining data model classes for public
APIs easy. Like with normal Kotlin data classes, all you have to do is provide properties in your
class's primary constructor. With the @Poko annotation, this compiler plugin automatically
generates toString, equals, and hashCode functions. Poko is compatible with all Kotlin
Multiplatform targets.
Mark your class as a @Poko class instead of a data class:
@Poko class MyData(
val int: Int,
val requiredString: String,
val optionalString: String?,
)
And reap the benefits of a readable toString and working equals and hashCode. Unlike normal
data classes, no copy or componentN functions are generated.
Like normal data classes, Poko classes must have at least one property in their primary constructor.
Non-property parameters in the primary constructor are ignored, as are non-constructor properties.
Any of the three generated functions can be overridden manually, in which case Poko will not
generate that function but will still generate the non-overridden functions. Using array properties
is not recommended, and if they are used, it is recommended to override equals and hashCode
manually.
By default, the dev.drewhamilton.poko.Poko annotation is used to mark classes for Poko generation.
If you prefer, you can create a different annotation and supply it to the Gradle plugin.
apply plugin: "dev.drewhamilton.poko"
poko {
pokoAnnotation.set "com/example/MyData"
}
Nested annotations mentioned below can optionally be added with the same name to the base annotation
and used for their respective features. For example, @MyData.ReadArrayContent will cause the
annotated property's contents to be used in the Poko-generated functions.
Use @Poko.EqualsAndHashCode instead of the base @Poko annotation to generate only the equals
and hashCode functions for the annotated class. Use @Poko.ToString to generate only the
toString function.
By default, Poko does nothing to inspect the contents of array properties. This aligns with the behavior of data classes.
Poko consumers can change this behavior on a per-property basis with the @Poko.ReadArrayContent
annotation. On properties of a typed array type, this annotation will generate a contentDeepEquals
check. On properties of a primitive array type, this annotation will generate a
check. And on properties of type or of a generic type, this annotation will generate a
statement that disambiguates the many array types at runtime and uses the appropriate
or check. In all cases, the corresponding content-based
and are generated for the property as well.
Using arrays as properties in data types is not generally recommended: arrays are mutable, and
mutating data can affect the results of equals and hashCode over time, which is generally
unexpected. For this reason, @Poko.ReadArrayContent should only be used in very
performance-sensitive APIs.
It is sometimes useful to omit some properties from consideration when generating the Poko
functions. This can be done with the experimental @Poko.Skip annotation. Properties with this
annotation will be excluded from all three generated functions. For example:
@Poko class Data(
val id: String,
@Poko.Skip val callback: () -> Unit,
) : CircuitUiState
Data("a") { println("a") } == Data("a") { println("not a") } // yields `true`
Poko aims to be compatible with recent and new IntelliJ IDEs. If the
kotlin.k2.only.bundled.compiler.plugins.enabled registry option is disabled, IntelliJ should
display hints indicating which functions Poko is generating, and should display Poko-specific
warnings and errors.
If your IDE is incompatible with Poko for some reason, this integration can be partially or fully
disabled with the firIdeMode configuration option.
poko {
firIdeMode.set(PokoFirIdeMode.CHECKERS_ONLY)
}
Poko is available on Maven Central. It is experimental, and the API may undergo breaking changes before version 1.0.0. Kotlin compiler plugins in general are experimental and new versions of Kotlin might break something in this compiler plugin.
Since the Kotlin compiler has frequent breaking changes, different versions of Kotlin are exclusively compatible with specific versions of Poko.
*Versions prior to 0.7.0 use plugin name dev.drewhamilton.extracare.
Snapshots of the development version are available in Sonatype's Snapshots repository.
Releases are signed with this key.
pub rsa4096 2020-02-02
09939C73246B4BA7444CAA453D002DBC5EA9615F
uid Drew Hamilton <drew.hamilton.0@gmail.com>
sig 3D002DBC5EA9615F 2020-02-02
To use Poko, apply the Gradle plugin in your project:
// Root project:
plugins {
id("dev.drewhamilton.poko") apply false
}
// Per module:
plugins {
id("dev.drewhamilton.poko")
}
Copyright 2020 Drew Hamilton
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance the License.
You may obtain a copy of the License at
http:
Unless applicable law agreed to writing, software
distributed under the License distributed an BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express implied.
See the License the specific language governing permissions
limitations under the License.
Surfaced from shared tags and platforms — no rankings paid for.
contentEqualsAnywhencontentDeepEqualscontentEqualshashCodetoString| Kotlin version | Poko version |
|---|
| 2.4.0+ | 0.23.0 |
| 2.3.20 – 2.3.21 | 0.22.1 |
| 2.3.0 – 2.3.10 | 0.21.3 |
| 2.2.20 – 2.2.21 | 0.20.2 |
| 2.2.0 – 2.2.10 | 0.19.3 |
| 2.1.0 – 2.1.21 | 0.18.7 |
| 2.0.0 – 2.0.21 | 0.17.2 |
| 1.9.0 – 1.9.24 | 0.15.3 |
| 1.8.20 – 1.8.22 | 0.13.1 |
| 1.8.0 – 1.8.10 | 0.12.0 |
| 1.7.0 – 1.7.21 | 0.11.0 |
| 1.6.20 – 1.6.21 | 0.10.0 |
| 1.6.0 – 1.6.10 | 0.9.0 |
| 1.5.0 – 1.5.31 | 0.8.1 |
| 1.4.30 – 1.4.32 | 0.7.4 |
| 1.4.20 – 1.4.21 | 0.5.0* |
| 1.4.0 – 1.4.10 | 0.3.1* |
| 1.3.72 | 0.2.4* |