web3j web3j is a lightweight, reactive, type safe Java and Android library for 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.Features Complete implementation of Ethereum’s JSON-RPC client API over HTTP and IPC Ethereum wallet support Reactive-functional API for working with filters Auto-generation of Java smart contract wrappers to create, deploy, transact with and call smart contracts from native Java code Support for Parity’s Personal, and Geth’s Personal client APIs Support for 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 Dependencies It has seven runtime dependencies: RxJava for its reactive-functional API Apache HTTP Client Jackson Core for fast JSON serialisation/deserialisation Bouncy Castle and Java Scrypt for crypto JavaPoet for generating smart contract wrappers Jnr-unixsocket for *nix IPC Contents: Getting Started Maven Gradle Start a client Start sending requests IPC Filters Transactions Working with smart contracts with Java smart contract wrappers Further details Transactions Obtaining Ether Mining on testnet/private blockchains Gas Transaction mechanisms Transaction signing via an Ethereum client Offline transaction signing Creating and working with wallet files Signing transactions The transaction nonce Transaction types Transfer of Ether from one party to another Creation of a smart contract Transacting with a smart contract Querying the state of a smart contract Smart Contracts Getting started with Solidity Compiling Solidity source code Deploying and interacting with smart contracts Smart contract examples EIP-20 Ethereum token standard smart contract Solidity smart contract wrappers Construction and deployment Transaction Managers Specifying the Chain Id on Transactions (EIP-155) Invoking transactions and events Calling constant methods Examples Filters and Events Block and transaction filters Replay filters Topic filters and EVM events A note on functional composition Further examples Command Line Tools Wallet tools Solidity smart contract wrapper generator Management APIs Using Infura with web3j Signing up InfuraHttpClient Certificate installation Connecting Transactions Troubleshooting I’m submitting a transaction, but it’s not being mined I want to see details of the JSON-RPC requests and responses I want to obtain some Ether on Testnet, but don’t want to have to mine it myself How do I obtain the return value from a smart contract method invoked by a transaction?

Is it possible to send arbitrary text with transactions?Projects using web3j Developer Guide Building web3j Generating documentation Links and Useful Resources Thanks and CreditsGetting started writing dapps is hard.You've got a lot of moving pieces, and half of them are in beta release.bitcoin otcIt's great because you can make a huge impact as an early adopter, but being a pioneer you sacrifice the convince you'll find in more mature spaces.bitcoin expires dailyThis article should give you some understanding of the key technologies currently in the Ethereum space.jual bitcoin miningHaving a general understanding of the Ethereum development ecosystem will save you a lot of headaches when building dapps.cay bitcoin nhu the nao

Here's an overview of 5 essential tools to get you started: A simple Ethereum testnet node for development.This works as a substitute for the real Ethereum network, which you will want to use for production.solc is the Solidity Compiler.Many Ethereum nodes include a solc implementation.It is also packaged as a standalone NPM module for offline compiling.litecoin cloud mining freepile() which doesn't rely on the external node.bitcointalk new usersThe key connection between the Ethereum network and your dapp.bitcoin forbes 2013Web3 allows you to compile, deploy, and interact with your smart contracts.best bitcoin otcOnce you upload a contract and save it's ABI you can call your contract functions as if they were just Javascript objects!hulk bitcoins

SimpleStorage.set(value) Pudding is a wrapper around web3.It provides conveniences like callback hooks that trigger after your contract transactions complete.Pudding on GitHub If all that stuff in solc and web3 sounded complex, then you might want to use a Dapp framework.Truffle and Embark are the most well known frameworks.Both frameworks handle compiling, deploying, and interfacing with your contracts.They also have sensible conventions for testing and app structure.[Updated 2/24/2017]: A couple months ago, Embark released version 2.0.I have not had a chance to explore the features of this release in depth.Truffle also released 3.0 which included very significant changes like modularizing the libraries' codebase.From my perspective, I would lean towards using Truffle as it is being supported by many developers at ConsenSys and seems to be taking a more flexible approach than Embark.However, try them out yourself and see what works best for you!The folks over at Dapphub released their internal dev tools Dapple and Dappsys.