# web3j
**Repository Path**: hyperledger/web3j
## Basic Information
- **Project Name**: web3j
- **Description**: Lightweight Java and Android library for integration with Ethereum clients
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No
## Statistics
- **Stars**: 1
- **Forks**: 1
- **Created**: 2024-04-11
- **Last Updated**: 2024-11-01
## Categories & Tags
**Categories**: Uncategorized
**Tags**: None
## README
Web3j: Web3 Java Ethereum Ðapp API
==================================
[](https://docs.web3j.io)
[](https://github.com/web3j/web3j/actions/workflows/build.yml)
[](https://codecov.io/gh/web3j/web3j)
[](https://discord.gg/A9UXfPF2tS)
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](https://www.ethereum.org/)
blockchain, without the additional overhead of having to write your own
integration code for the platform.
The [Java and the Blockchain](https://www.youtube.com/watch?v=ea3miXs_P6Y) talk provides
an overview of blockchain, Ethereum and Web3j.
NEW! Get involved!
--------
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](https://lists.hyperledger.org/g/web3j) - Check our last updates!
- [Calendar Invite](https://lists.hyperledger.org/g/web3j/ics/invite.ics?repeatid=57401) - Add the contributor call to your calendar!
Features
--------
- Complete implementation of Ethereum's
[JSON-RPC](https://github.com/ethereum/wiki/wiki/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](http://solidity.readthedocs.io/en/latest/using-the-compiler.html#using-the-commandline-compiler)
and
[Truffle](https://github.com/trufflesuite/truffle-contract-schema)
definition formats supported)
- Reactive-functional API for working with filters
- [Ethereum Name Service (ENS)](https://ens.domains/) support
- Support for Parity's
[Personal](https://github.com/paritytech/parity/wiki/JSONRPC-personal-module),
and Geth's
[Personal](https://github.com/ethereum/go-ethereum/wiki/Management-APIs#personal)
client APIs
- Support for [Alchemy](https://docs.alchemyapi.io/alchemy/guides/getting-started#web-3-j) and [Infura](https://infura.io/), 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](https://github.com/web3j/quorum)
- Support for [EEA Privacy features as described in EEA
documentation](https://entethalliance.org/technical-documents/) and
implemented in [Hyperledger
Besu](https://besu.hyperledger.org/en/latest/Reference/API-Methods/#eea-methods).
It has five runtime dependencies:
- [RxJava](https://github.com/ReactiveX/RxJava) for its
reactive-functional API
- [OKHttp](https://square.github.io/okhttp/)
for HTTP connections
- [Jackson Core](https://github.com/FasterXML/jackson-core) for fast
JSON serialisation/deserialization
- [Bouncy Castle](https://www.bouncycastle.org/) for
crypto
- [Jnr-unixsocket](https://github.com/jnr/jnr-unixsocket) for \*nix
IPC (not available on Android)
- [Java-WebSocket](https://github.com/TooTallNate/Java-WebSocket)
It also uses [JavaPoet](https://github.com/square/javapoet) for
generating smart contract wrappers.
QuickStart
---------
The simplest way to start your journey with Web3j is to create a project.
We provide this functionality using the [Web3j CLI](http://docs.web3j.io/latest/command_line_tools/). This latter can be installed as follows:
For Unix:
```shell script
curl -L get.web3j.io | sh && source ~/.web3j/source.sh
```
For Windows, in Powershell:
```shell script
Set-ExecutionPolicy Bypass -Scope Process -Force; iex ((New-Object System.Net.WebClient).DownloadString('https://raw.githubusercontent.com/hyperledger/web3j-installer/main/installer.ps1'))
```
Create a new project by running:
```shell script
$ web3j new
```
Or use our [Maven](https://github.com/web3j/web3j-maven-plugin) or
[Gradle](https://github.com/web3j/web3j-gradle-plugin) plugins to
generate java files from Solidity contracts.
#### Please head to the [Web3j Documentation](https://docs.web3j.io) for further instructions on using Web3j.
Maven
-----
Java:
```xml
org.web3jcore4.12.2
```
**Note:** The Web3j Java binaries are compiled using Java 17. Java 17 or a more recent version is required to use Web3j
as a dependency.
Android:
```xml
org.web3jcore4.8.9-android
```
Gradle
------
Java:
```groovy
implementation ('org.web3j:core:4.12.2')
```
Android:
```groovy
implementation ('org.web3j:core:4.8.9-android')
```
Build instructions
------------------
Web3j includes integration tests for running against a live Ethereum
client. If you do not have a client running, you can exclude their
execution as per the below instructions.
To run a full build (excluding integration tests):
``` {.sourceCode .bash}
$ ./gradlew check
```
To run the integration tests, you will need to set up these variables in order to pull the Docker
images from the Docker Hub registry:
- `registry.username`
- `registry.password`
Then run the following command:
``` {.sourceCode .bash}
$ ./gradlew -Pintegration-tests=true :integration-tests:test
```
If you do not want the integration test to run:
``` {.sourceCode .bash}
$ ./gradlew -Pintegration-tests=false :test
```
Check the [Docker client API](https://github.com/docker-java/docker-java/blob/master/docs/getting_started.md#instantiating-a-dockerclientconfig)
for more information on configuration options.
Projects using Web3j
------------------
Commercial support and training
-------------------------------
Commercial support and training is available from
[web3labs.com](https://www.web3labs.com/web3j-sdk).
License
------
Apache 2.0
