This article explains how to construct and send Ethereum JSON‑RPC calls such as net_version through a WebSocket connection using the Web3j Java library, including source code analysis, request construction, and a practical example with console output.
This guide walks through obtaining an Infura API key, using Web3j’s HTTP API to connect to Ethereum’s mainnet, creating and sending requests, handling responses, and generating local wallets with private keys, while highlighting common pitfalls and asynchronous issues for Java developers.
The article analyzes why using Web3j's sendAsync() method can prevent the JVM from terminating, examines the underlying thread‑pool implementation in org.web3j.utils.Async, and offers debugging steps and possible work‑arounds for developers.
This article walks through setting up a local Ethereum testnet using Ganache, configuring a Java project with Web3j, and implementing code to query the network and perform a signed Ether transfer, providing step-by-step instructions, code snippets, and screenshots for beginners.
This step‑by‑step guide walks developers through setting up a blockchain development environment, creating and deploying an ERC‑20 token contract with Truffle and OpenZeppelin, and integrating the contract into an Android app using Web3j to query balances and perform token transfers.
This tutorial walks you through the complete process of setting up a local Ethereum node, developing and deploying a Solidity token contract with Truffle, generating Java wrappers using Web3j, and integrating the contract into an Android app to perform transfers and balance queries.
This guide compiles the most frequent Ethereum synchronization problems—such as blocks lagging by dozens, the sync process stalling at 99%, zero block height or balance readings, and abnormal logs—and provides step‑by‑step commands, hardware tips, cache settings, and log‑analysis techniques to diagnose and resolve them.
This guide explains how to write Ethereum smart contracts in Solidity, Serpent, or LLL, compile them to bytecode, generate Java wrappers with Web3j, manage transactions and events, use filters, and operate the Web3j command‑line tool for wallet and contract tasks.
