Nvim: add jdtls 🚀

home/.config/nvim/ftplugin/java.lua

@@ -0,0 +1,19 @@
+local nvim_local_dir = vim.fn.expand('~/.local/share/nvim')
+
+local project_name = vim.fn.fnamemodify(vim.fn.getcwd(), ':p:h:t')
+local workspace_dir = nvim_local_dir .. '/jdtls-workspaces/' .. project_name
+require('jdtls').start_or_attach({
+    cmd = {
+        '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', '-Xms1g',
+        '--add-modules=ALL-SYSTEM', '--add-opens',
+        'java.base/java.util=ALL-UNNAMED', '--add-opens',
+        'java.base/java.lang=ALL-UNNAMED', -- 💀
+        '-jar', nvim_local_dir ..
+            '/lsp_servers/jdtls/plugins/org.eclipse.equinox.launcher_1.6.400.v20210924-0641.jar',
+        '-configuration', nvim_local_dir .. '/lsp_servers/jdtls/config_linux',
+        '-data', workspace_dir
+    }
+})

home/.config/nvim/lua/pluginconf/lsp.lua

@@ -49,8 +49,10 @@ local capabilities = vim.lsp.protocol.make_client_capabilities()
 capabilities = require('cmp_nvim_lsp').update_capabilities(capabilities)
 
 -- Register a handler that will be called for all installed servers.
--- Alternatively, you may also register handlers on specific server instances instead (see example below).
 lsp_installer.on_server_ready(function(server)
+    -- Don't setup jdtls here since it is done by nvim-jdtls
+    if server.name == "jdtls" then return end
+
     local opts = {}
 
     -- Lua specific settings
@@ -79,6 +81,6 @@ lsp_installer.on_server_ready(function(server)
     end
 
     opts.on_attach = buf_map_keys
-	opts.capabilities = capabilities
+    opts.capabilities = capabilities
     server:setup(opts)
 end)

home/.config/nvim/lua/pluginmanager.lua

@@ -64,6 +64,9 @@ require('packer').startup(function()
     -- Install LSP server executables
     use 'williamboman/nvim-lsp-installer'
 
+	-- Additional LSP features for Java
+	use 'mfussenegger/nvim-jdtls'
+
     -- Completion
     use 'hrsh7th/nvim-cmp' -- Autocompletion plugin
     use 'hrsh7th/cmp-nvim-lsp' -- LSP source for nvim-cmp