web3j 4.0 Released

Building on the fantastic work of our community, we have taken web3j-4.0.0 out of alpha and made it available as a full release.

As you may recall web3j-4.0.0-alpha was released in time for Devcon4, to provide our community with some sought after features, such as Reactive Streams 2.0, a BIP44 implementation, plus support for PegaSys’ Pantheon client and many other neat changes.

Changeset

In addition to alpha release change set web3j-4.0.3 includes the following

Improvements to the Solidity code generation: #672
Remove deprecated methods: #508
Improve implementation of MnemonicUtils: #665
Update to CLI usage string: #660
Updated OkHttp CipherSuites to include all INFURA CiperSuites: #757
Remove *.bin file requirement for contract wrapper generation: #408
Prefix message signing according to eth_sign: #761
Support for Pantheon specific RPC calls #767, #792
Exception logging and format #746, #784, #785
NPE for logs without topics #708
NPE when an error is encountered before a listener is set #731
Allow use of Java keywords as Solidity function names #776
Add support for CLEARTEXT HTTP communication #718
Publish/subscribe documentation for #458 — #768
Fix invalid index error on node disconnection #713
Make “crypto” module less dependent on 3rd party libraries (ease Android integration) #618
Change the visibility of some methods to ease hardware integration #679

Thank you to all our community and contributors for making this possible.

What do I need to do?

If you previously upgraded to 4.0.0-alpha then the process is straightforward and no changes are required; just add a dependency onto web3j-4.0.3.

If you were on 3.6 or a slightly older release then you will need to regenerate your smart contract wrappers to use this release, in addition to migrating across your method calls to use the updated function names as per the RxJava 2.0 section; refer to the blog post on the 4.0.0-alpha release for further detail.