Add Java LSP support

3 files changed, 65 insertions, 2 deletions

diff --git a/lua/config/jdtls.lua b/lua/config/jdtls.lua
new file mode 100644
index 0000000..04f92c4
--- /dev/null
+++ b/lua/config/jdtls.lua
@@ -0,0 +1,54 @@
+-- ~/.config/nvim/lua/config/jdtls.lua
+return function()
+	local jdtls = require("jdtls")
+
+	local cmp_ok, cmp_nvim_lsp = pcall(require, "cmp_nvim_lsp")
+	local capabilities = vim.lsp.protocol.make_client_capabilities()
+	if cmp_ok then
+		capabilities = cmp_nvim_lsp.default_capabilities(capabilities)
+	end
+
+	local root_dir = require("jdtls.setup").find_root({ ".git", "pom.xml", "build.gradle", "gradlew", ".project", "mvnw" })
+	if not root_dir then
+		root_dir = vim.fn.getcwd()
+	end
+
+	local project_name = vim.fn.fnamemodify(root_dir, ":p:h:t")
+	local workspace_dir = vim.fn.stdpath("data") .. "/jdtls-workspace/" .. project_name
+
+	local config = {
+		cmd = {
+			"jdtls",
+			"-data", workspace_dir,
+		},
+		root_dir = root_dir,
+		capabilities = capabilities,
+		on_attach = function(client, bufnr)
+			local opts = { noremap = true, silent = true, buffer = bufnr }
+			vim.keymap.set("n", "gd", vim.lsp.buf.definition, opts)
+			vim.keymap.set("n", "K", vim.lsp.buf.hover, opts)
+			vim.keymap.set("n", "<leader>rn", vim.lsp.buf.rename, opts)
+			vim.keymap.set("n", "gr", vim.lsp.buf.references, opts)
+			vim.keymap.set("n", "<leader>ca", vim.lsp.buf.code_action, opts)
+			vim.keymap.set("n", "<leader>d", vim.diagnostic.open_float, opts)
+			-- jdtls-specific mappings
+			vim.keymap.set("n", "<leader>oi", jdtls.organize_imports, opts)
+		end,
+		settings = {
+			java = {
+				signatureHelp = { enabled = true },
+				completion = {
+					favoriteStaticMembers = {},
+				},
+				sources = {
+					organizeImports = {
+						starThreshold = 9999,
+						staticStarThreshold = 9999,
+					},
+				},
+			},
+		},
+	}
+
+	jdtls.start_or_attach(config)
+end
diff --git a/lua/config/lsp.lua b/lua/config/lsp.lua
index 67e80eb..01ada61 100644
--- a/lua/config/lsp.lua
+++ b/lua/config/lsp.lua
@@ -52,7 +52,7 @@ return function()
 		rust_analyzer  = {},  -- Rust
 		zls            = {},  -- Zig
 		hls            = {},  -- Haskell
-		jdtls          = {},  -- Java
+		-- jdtls handled by nvim-jdtls plugin
 		asm_lsp        = {},  -- Assembly (if you install it)
 		clojure_lsp    = {},  -- Clojure
 		racket_langserver = {},  -- Racket (Scheme dialect)
diff --git a/lua/plugins/init.lua b/lua/plugins/init.lua
index 394a75c..90f5ecd 100644
--- a/lua/plugins/init.lua
+++ b/lua/plugins/init.lua
@@ -119,8 +119,17 @@ return {
 	-- },
 	'RaafatTurki/hex.nvim',
 
+	-- Java LSP
+	{
+		'mfussenegger/nvim-jdtls',
+		ft = 'java',
+		config = function()
+			require("config.jdtls")()
+		end,
+	},
+
 	-- Debugging
-	'mfussenegger/nvim-dap', 
+	'mfussenegger/nvim-dap',
 
 	-- Git
 	'tpope/vim-fugitive',