This library provides a Java wrapper around all the methods exposed by a Polkadot/Subtrate network client and defines all the types exposed by a node.

• packages -- Polkadot/substrate api Java implementation.
• examples -- Demo projects (Gradle).
• examples_runnable -- Demo executable JARs.

Java 1.8

The Java version is based on JS commit ff25a85ac20687de241a84e0f3ebab4c2920df7e.

The working substrate version is 1.0.0-41ccb19c-x86_64-macos. Newer substrate may be not supported.

The API is split up into a number of internal packages

• @polkadot/api The API library, providing both Promise and RxJS Observable-based interfaces. This is the main user-facing entry point.
• @polkadot/rpc RPC library.
• @polkadot/type Basic types such as extrinsics and storage.
• @polkadot/types Codecs for all Polkadot primitives.

• See the generated JavaDoc in /doc folder. Or visit the document site
• To generate JavaDoc by yourself, reference gendoc.sh in the root folder
• To understand how the system works, you may reference Substrate and Polkadot Network

The project uses Gradle as build tool. You need to install Gradle.

1. git clone https://github.com/polkadot-java/api.git
2. cd api
3. gradle build
4. Get the JARs in folder build/libs/
5. Add the JARs into your projects.

1. git clone https://github.com/polkadot-java/api.git
2. Import the gradle project in folder api/packages to your workspace.
3. Add links or dependencies in the IDE. This is different in different IDEs, please reference to your IDE document.

1. See polkadot-java/sr25519/readme.md to compile sr25591 library (Rust and C++).
2. See polkadot-java/sr25519/cpp/compile.sh how to compile the JNI shared library.
3. See polkadot-java/sr25519/libs/readme.md how to use the JNI in the Java API.

1. Install substrate local node:
   https://github.com/paritytech/substrate

2. Running the samples:
   There are several runnable samples. To run the samples, go to folder examples_runnable/LastestDate (such as examples_runnable/20190525), then run each shell script.

3. To change the Substrate address, change the endPoint variable in each demo main file.