No need to put up with jdtls nonsense anymore. Just install and start writing public static void main(String[] args).

• ✅ Diagnostics & Auto Completion
• ✅ Automatic DAP debug configuration
• ❌ Running tests

• Uses nvim-lspconfig to setup jdtls
• Realtime server settings updates is possible using neoconf
• Everything necessary will be installed automatically (except JDKs)
• Uses jdtls and auto loads jdtls plugins from mason.nvim
  • Supported plugins are,
    • lombok
    • java-test
    • java-debug-adapter
• Typed & documented APIs
• No callback hells I promise

Using lazy.nvim

return {
  'nvim-java/nvim-java',
  dependencies = {
    'nvim-java/nvim-java-core',
    'neovim/nvim-lspconfig',
    'williamboman/mason.nvim',
    'mfussenegger/nvim-dap',
  },
  event = 'VeryLazy',
  opts = {},
}

require('lspconfig').jdtls.setup({})

Yep! That's all :)

nvim-jdtls is a plugin that follows "Keep it simple, stupid!" approach. If you love customizing things by yourself, then give nvim-jdtls a try.