added java LS support (finally!)

neovim/.config/nvim/ftplugin/java.lua

@@ -0,0 +1,82 @@
+local opts = {
+	cmd = {},
+	settings = {
+		java = {
+			signatureHelp = { enabled = true },
+			completion = {
+				favoriteStaticMembers = {},
+				filteredTypes = {
+					-- "com.sun.*",
+					-- "io.micrometer.shaded.*",
+					-- "java.awt.*",
+					-- "jdk.*",
+					-- "sun.*",
+				},
+			},
+			sources = {
+				organizeImports = {
+					starThreshold = 9999,
+					staticStarThreshold = 9999,
+				},
+			},
+			codeGeneration = {
+				toString = {
+					template = "${object.className}{${member.name()}=${member.value}, ${otherMembers}}",
+				},
+				useBlocks = true,
+			},
+			configuration = {
+				runtimes = {
+					{
+						name = "JavaSE-1.8",
+						path = "/Library/Java/JavaVirtualMachines/amazon-corretto-8.jdk/Contents/Home",
+						default = true,
+					},
+					{
+						name = "JavaSE-17",
+						path = "/Library/Java/JavaVirtualMachines/jdk-17.jdk/Contents/Home",
+					},
+					{
+						name = "JavaSE-19",
+						path = "/Library/Java/JavaVirtualMachines/jdk-19.jdk/Contents/Home",
+					},
+				},
+			},
+		},
+	},
+}
+local jdtls_config = opts
+local pkg_status, jdtls = pcall(require,"jdtls")
+if not pkg_status then
+	vim.notify("unable to load nvim-jdtls", "error")
+	return {}
+end
+
+-- local jdtls_path = vim.fn.stdpath("data") .. "/mason/packages/jdtls"
+local jdtls_bin = vim.fn.stdpath("data") .. "/mason/bin/jdtls"
+
+local root_markers = { ".gradle", "gradlew", ".git" }
+local root_dir = jdtls.setup.find_root(root_markers)
+local home = os.getenv("HOME")
+local project_name = vim.fn.fnamemodify(root_dir, ":p:h:t")
+local workspace_dir = home .. "/.cache/jdtls/workspace/" .. project_name
+
+opts.cmd = {
+	jdtls_bin,
+	"-data",
+	workspace_dir,
+}
+
+
+local on_attach = function(client, bufnr)
+	jdtls.setup.add_commands() -- important to ensure you can update configs when build is updated
+	-- if you setup DAP according to https://github.com/mfussenegger/nvim-jdtls#nvim-dap-configuration you can uncomment below
+	-- jdtls.setup_dap({ hotcodereplace = "auto" })
+	-- jdtls.dap.setup_dap_main_class_configs()
+
+	-- you may want to also run your generic on_attach() function used by your LSP config
+end
+
+opts.on_attach = on_attach
+opts.capabilities = vim.lsp.protocol.make_client_capabilities()
+jdtls.start_or_attach(jdtls_config)

neovim/.config/nvim/lua/packages.lua

@@ -62,8 +62,8 @@ return require('packer').startup(function(use)
 				require('LSPconfig')
 			end
 		},
-		{'simrat39/rust-tools.nvim',
-		}
+		{'simrat39/rust-tools.nvim',},
+		{'mfussenegger/nvim-jdtls',},
 	}
 
 	use {'hrsh7th/nvim-cmp',