Poolster Java plugin

poolster-plugin-java renders SDK packages from Poolster's neutral API model, using a Java 17+ HttpClient/Jackson client. All generation runs in Rust.

use poolster::prelude::*;
use poolster_plugin_java::PackageExt as _;
use poolster_plugin_java as java;

let release = ProfileSet::new("sdk")
    .package(java::package("java")
        .name("email-sdk")
        .with(java::sdk()));
let tree = poolster::generate(&api, release)?;
tree.write_to("generated")?;

SDKs are namespaced by default. Choose java::sdk().flat() or .namespaced() explicitly, or supply a shared Common default. Namespaced clients expose resources such as client.contacts().get(input); flat clients use client.getContact(input). Generated packages include Maven and Gradle metadata. See STYLE_GUIDE.md.

When depending on this plugin without the poolster facade, import poolster_plugin_java::PackageExt and compose its package through poolster_core::engine::Packages. Supply a security catalog when your API declares named security schemes.

See configuration for every generation option and the generated package's README for exact operation signatures.

Use java::sdk().open_enums(true) to preserve future enum values returned by an API. This opt-in emits immutable wire-value classes rather than Java enums. Known constants, value() and values() remain available; value equality and Jackson serialization preserve unknown strings. fromKnownValue() provides strict validation for request construction, while fromValue() accepts future response values. isKnown() distinguishes the two. Java enum switches and Enum APIs require the default closed-enum policy.

Open object records retain unknown properties in a typed additional-properties map using Jackson's any-getter/any-setter support. The map serializes at original JSON keys, preserves null values, and cannot shadow a declared property. When the schema omits additionalProperties or permits any value, the existing constructor for declared fields remains available. Explicitly closed schemas retain their existing generated record behavior. Record fields still do not distinguish omitted optional properties from explicit null values.

SDK authors can bundle customer middleware through Package::middleware or poolster.json middleware entries with source, path, and symbol. The source is copied into the generated package and registered automatically; SDK callers do not configure middleware. Java's symbol names a class in the client package with public static HttpClient wrap(HttpClient next). Put it at src/main/java/<generated/package>/<Symbol>.java. Return a delegating HttpClient that preserves its abstract methods, body handler types and interruption. The first configured factory is outermost, and SDK retries call the resulting transport for each attempt. async_symbol and alternate signatures are rejected. Files are generator-owned, collisions fail, and regeneration refreshes them from the author source. Native compilation checks the factory's signature.

Large SDKs use byte-aware operation and resource inheritance partitions with a 128 KiB grouping budget, retaining the original public Client and resource methods. Existing declaration-count ceilings still apply. Large typed model holders also use field-part superclass files; Jackson annotations, inherited getters, fluent setters, presence types and extra-property guards remain active. Single enum/method/request declarations that exceed the budget remain intact and are listed with their exact path and bytes in .poolster/source-layout-diagnostics.json. Generated-file ownership refuses regeneration over local edits.