Web3j is a lightweight, highly modular, reactive, type safe Java and Android library for working with Smart Contracts and integrating with clients (nodes) on the Ethereum network:
This allows you to work with the Ethereum blockchain, without the additional overhead of having to write your own integration code for the platform.
The Java and the Blockchain talk provides an overview of blockchain, Ethereum and Web3j.
Since Web3J moved under Hyperledger we started to do Web3J Contributors calls every 2 weeks! Subscribe to our community page and to see check our call schedule. Your contribution matters!
- Community Link - Check our last updates!
- Calendar Invite - Add the contributor call to your calendar!
- Complete implementation of Ethereum's JSON-RPC client API over HTTP and IPC
- Ethereum wallet support
- Auto-generation of Java smart contract wrappers to create, deploy, transact with and call smart contracts from native Java code (Solidity and Truffle definition formats supported)
- Reactive-functional API for working with filters
- Ethereum Name Service (ENS) support
- Support for Parity's Personal, and Geth's Personal client APIs
- Support for Alchemy and Infura, so you don't have to run an Ethereum client yourself
- Comprehensive integration tests demonstrating a number of the above scenarios
- Command line tools
- Android compatible
- Support for JP Morgan's Quorum via web3j-quorum
- Support for EEA Privacy features as described in EEA documentation and implemented in Hyperledger Besu.
It has five runtime dependencies:
- RxJava for its reactive-functional API
- OKHttp for HTTP connections
- Jackson Core for fast JSON serialisation/deserialization
- Bouncy Castle for crypto
- Jnr-unixsocket for *nix IPC (not available on Android)
- Java-WebSocket
It also uses JavaPoet for generating smart contract wrappers.
The simplest way to start your journey with Web3j is to create a project. We provide this functionality using the