Running on Monorepo with multiple Java projects

[juhaku]

Hi,

Is there any remedy for running this on monorepo with lots of different kind of projects in with different languages. Including multiple separate Java projects with multiple modules. Currently by doing so I get the following warning:

Multiple LSP clients found that support vscode.java.resolveMainClass you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.resolveJavaExecutable you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.checkProjectSettings you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.resolveClasspath you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.resolveJavaExecutable you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.checkProjectSettings you should have at most one JDTLS server running
Multiple LSP clients found that support vscode.java.resolveClasspath you should have at most one JDTLS server running

The approximate project layout might be for me as seen below, and I want to "develop" as "root" as my working directory. Right now the config will start multiple LSP clients one for each module, but that is easily eating all the memory but instead there should be only one lsp client running, but is it even possible with the configuration and monorepo setup?

root
  java project 1
   module 1
   module 2
   module 3
 other project
 another other project
 java project 2
   module 1
  module 2
  module 3
  module 4
 java project 3
 node project
 ...

My java config lua file is as follows. It should be according to the instructions found from the repo.

local lsp_config = require("plugins.lsp-config")
-- See `:help vim.lsp.start_client` for an overview of the supported `config` options.
local home = os.getenv("HOME")

local jdtls_path = home .. "/.local/share/nvim/mason/packages/jdtls"
local jdtls_launcher = "org.eclipse.equinox.launcher_*.jar"
local java_location = "/usr/lib/jvm"

local project_name = vim.fn.fnamemodify(vim.fn.getcwd(), ":p:h:t")
local workspace_dir = home .. "/.config/jdtls/" .. project_name

local bundles = {
	vim.fn.glob(
		home
			.. "/.config/nvim/lib/java-debug/com.microsoft.java.debug.plugin/target/com.microsoft.java.debug.plugin-*.jar"
	),
}
vim.list_extend(bundles, vim.split(vim.fn.glob(home .. "/.config/nvim/lib/vscode-java-test/server/*.jar"), "\n"))

local jdtls = require("jdtls")

local extendedClientCapabilities = jdtls.extendedClientCapabilities
extendedClientCapabilities.resolveAdditionalTextEditsSupport = true

local function get_jdks()
	local jdk_paths = vim.fn.systemlist("fd java " .. java_location .. " -d 1")
	local jdks = {}

	for _, path in ipairs(jdk_paths) do
		local version = string.gsub(path, "[a-zA-Z/-]*", "")
		if tonumber(version) < 9 and tonumber(version) > 5 then
			version = "1." .. version
		end
		table.insert(jdks, {
			name = "JavaSE-" .. version,
			version = version,
			path = path,
		})
	end

	table.sort(jdks, function(a, b)
		return a.name < b.name
	end)

	return jdks
end

local function get_runtimes()
	local jdks = get_jdks()
	local last_version = jdks[#jdks].version

	local runtimes = {}
	for _, jdk in ipairs(jdks) do
		local default = false
		if jdk.version == last_version then
			default = true
		end

		table.insert(runtimes, {
			name = jdk.name,
			path = jdk.path,
			default = default,
		})
	end

	return runtimes
end

local function find_latest_java_path()
	local jdks = get_jdks()
	return jdks[#jdks].path
end

local config = {
	cmd = {
		-- use java 17 or never to run
		-- "/usr/lib/jvm/java-18-openjdk/bin/java",
		find_latest_java_path() .. "/bin/java",

		"-Declipse.application=org.eclipse.jdt.ls.core.id1",
		"-Dosgi.bundles.defaultStartLevel=4",
		"-Declipse.product=org.eclipse.jdt.ls.core.product",
		-- '-Dlog.protocol=true',
		"-Dlog.level=ALL",
		"-Xms4G",
		"-javaagent:" .. home .. "/.config/nvim/lib/lombok.jar",
		"--add-modules=ALL-SYSTEM",
		"--add-opens",
		"java.base/java.util=ALL-UNNAMED",
		"--add-opens",
		"java.base/java.lang=ALL-UNNAMED",

		"-jar",
		vim.fn.glob(jdtls_path .. "/plugins/" .. jdtls_launcher),

		"-configuration",
		jdtls_path .. "/config_linux",
		"-data",
		workspace_dir,
	},
	root_dir = require("jdtls.setup").find_root({ "mvnw", "gradlew", "pom.xml", "build.gradle", "build.gradle.kts" }),
	on_attach = function(client, bufnr)
		lsp_config.codelens_try_refresh()
		---@diagnostic disable-next-line: missing-fields
		require("jdtls").setup_dap({ hotcodereplace = "auto" })
		require("jdtls.dap").setup_dap_main_class_configs()
		-- require("jdtls.setup").add_commands()
		-- local dap = require("dap")
		-- -- add java debug attach config
		-- vim.fn.list_extend(dap.configurations.java, {
		-- 	{
		-- 		type = "java",
		-- 		request = "attach",
		-- 		name = "Debug (Attach) - Remote",
		-- 		hostName = "127.0.0.1",
		-- 		port = 5005,
		-- 	},
		-- })

		lsp_config.on_attach(client, bufnr)
	end,
	capabilities = lsp_config.capabilities,
	handlers = lsp_config.handlers,
	-- Here you can configure eclipse.jdt.ls specific settings
	-- See https://github.com/eclipse/eclipse.jdt.ls/wiki/Running-the-JAVA-LS-server-from-the-command-line#initialize-request
	-- for a list of options
	settings = {
		java = {
			import = {
				saveActions = {
					organizeImports = true,
				},
				maven = {
					enabled = true,
				},
				gradle = {
					enabled = true,
				},
			},
			maven = {
				downloadSources = true,
			},
			implementationsCodeLens = {
				enabled = true,
			},
			referencesCodeLens = {
				enabled = true,
			},
			inlayHints = {
				parameterNames = {
					enabled = "all",
				},
			},
			signatureHelp = {
				enabled = true,
			},
			configuration = {
				runtimes = get_runtimes(),
			},
			completion = {
				matchCase = "off",
				maxResults = 999,
			},
		},
	},
	init_options = {
		bundles = bundles,
		extendedClientCapabilities = extendedClientCapabilities,
	},
}

vim.api.nvim_create_autocmd({ "BufWritePost" }, {
	pattern = { "*.java" },
	callback = function()
		lsp_config.codelens_try_refresh()
	end,
})

-- This starts a new client & server,
-- or attaches to an existing client & server depending on the `root_dir`.
jdtls.start_or_attach(config)

vim.cmd([[
    command! -buffer -nargs=? -complete=custom,v:lua.require'jdtls'._complete_compile JdtCompile lua require('jdtls').compile(<f-args>)
    command! -buffer -nargs=? -complete=custom,v:lua.require'jdtls'._complete_set_runtime JdtSetRuntime lua require('jdtls').set_runtime(<f-args>)
    command! -buffer JdtUpdateConfig lua require('jdtls').update_project_config()
    command! -buffer JdtJol lua require('jdtls').jol()
    command! -buffer JdtBytecode lua require('jdtls').javap()
    command! -buffer JdtJshell lua require('jdtls').jshell()
]])

local keymap = vim.keymap
local opts = { noremap = true, silent = true }

keymap.set("n", "<leader><leader>o", ":lua require('jdtls').organize_imports()<CR>", opts)
keymap.set("n", "<leader>dn", ":lua require('jdtls').test_nearest_method()<CR>", opts)
keymap.set("n", "<leader>dc", ":lua require('jdtls').test_class()<CR>", opts)

-- nnoremap <A-o> <Cmd>lua require'jdtls'.organize_imports()<CR>
-- nnoremap crv <Cmd>lua require('jdtls').extract_variable()<CR>
-- vnoremap crv <Esc><Cmd>lua require('jdtls').extract_variable(true)<CR>
-- nnoremap crc <Cmd>lua require('jdtls').extract_constant()<CR>
-- vnoremap crc <Esc><Cmd>lua require('jdtls').extract_constant(true)<CR>
-- vnoremap crm <Esc><Cmd>lua require('jdtls').extract_method(true)<CR>

-- -- If using nvim-dap
-- -- This requires java-debug and vscode-java-test bundles, see install steps in this README further below.
-- nnoremap <leader>df <Cmd>lua require'jdtls'.test_class()<CR>
-- nnoremap <leader>dn <Cmd>lua require'jdtls'.test_nearest_method()<CR>

[juhaku]

To get back to this as I was refactoring my neovim configs. I this time read carefully that the "key" for the multiple instances of JDTLS language servers problem is the root_dir attribute in the server settings. The find_root does not handle some edge cases or at least I get the result I was not wishing for. However to solve the correct root_dir I tried with the lspconfig.utils.root_pattern function and that solves correctly the root dir for a monorepo case. Here is the working piece:

	root_dir = require("lspconfig").util.root_pattern(
		".git",
		"mvnw",
		"gradlew",
		"pom.xml",
		"build.gradle",
		"build.gradle.kts"
	)(vim.api.nvim_buf_get_name(vim.api.nvim_get_current_buf())),

You find my configs from here:
https://github.com/juhaku/nvim/blob/e05b805487cd2345e6f9b6e930724eeaaa4149c4/ftplugin/java.lua#L97..L104