The type java.lang.Object cannot be resolved.

[mrdgo]

Hey all,

maybe someone has resolved this issue before. When I open a java file, the jdtls starts as expected. But as soon as it is up, it marks my package declaration with The type java.lang.Object cannot be resolved. It is indirectly referenced from required .class files.. I can use the language service as expected: code actions, goto definition, etc. But somehow it doesn't know about the standard library. And yes, the runtime path exists and is valid - at least do I get an error when I add another entry with an invalid path. Help?

Here is my config:

local jdtls = require("jdtls")
local root_markers = { "gradlew", ".git" }
local root_dir = require("jdtls.setup").find_root(root_markers)
local home = os.getenv("HOME")
local workspace_folder = home .. "/.local/share/eclipse/" .. vim.fn.fnamemodify(root_dir, ":p:h:t")
-- :help vim.lsp.start_client` for an overview of the supported `config` options.

local bundles = {
	vim.fn.glob("/opt/java-debug/com.microsoft.java.debug.plugin/target/com.microsoft.java.debug.plugin-*.jar"),
}

vim.list_extend(bundles, vim.split(vim.fn.glob("/opt/vscode-java-test/server/*.jar"), "\n"))

local config = {
	cmd = {
		"/usr/lib/jvm/java-17-openjdk/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",
		"-Xms1g",
		"--add-modules=ALL-SYSTEM",
		"--add-opens",
		"java.base/java.util=ALL-UNNAMED",
		"--add-opens",
		"java.base/java.lang=ALL-UNNAMED",
		"-javaagent:" .. home .. "/.config/nvim/config/lombok.jar",
		"-jar",
		"/usr/share/java/jdtls/plugins/org.eclipse.equinox.launcher_1.6.500.v20230717-2134.jar",
		"-configuration",
		"/usr/share/java/jdtls/config_linux",
		"-data",
		workspace_folder,
	},
	root_dir = jdtls.setup.find_root({ ".git", "mvnw", "gradlew" }),
	settings = {
		java = {
			signatureHelp = { enabled = true },
			format = {
				settings = {
					url = " https://raw.githubusercontent.com/google/styleguide/gh-pages/eclipse-java-google-style.xml",
				},
			},
			configuration = {
				-- See https://github.com/eclipse/eclipse.jdt.ls/wiki/Running-the-JAVA-LS-server-from-the-command-line#initialize-request
				-- And search for `interface RuntimeOption`
				-- The `name` is NOT arbitrary, but must match one of the elements from `enum ExecutionEnvironment` in the link above
				runtimes = {
					{
						name = "JavaSE-17",
						path = "/usr/lib/jvm/java-17-openjdk/",
					},
				},
			},
		},
	},
	init_options = {
		bundles = bundles,
	},
	on_attach = function()
		require("lsp_on_attach").on_attach()

		jdtls.setup_dap({ hotcodereplace = "auto" })
		require("dap").configurations.java = {
			{
				type = "server",
				request = "attach",
				name = "Debug (Attach) - Remote",
				hostName = "127.0.0.1",
				port = 5005,
			},
		}
		jdtls.setup.add_commands()

		local jdt_maps = {
			oi = jdtls.organize_imports,
			ct = jdtls.test_class,
			nt = jdtls.test_nearest_method,
			-- e = "extract_variable(true)"
			-- m = "extract_method(true)"
		}

		-- Java specific
		for key, cmd in pairs(jdt_maps) do
			vim.keymap.set("n", "<Leader>s" .. key, cmd, { noremap = false, silent = true })
		end
	end,
}
-- This starts a new client & server,
-- or attaches to an existing client & server depending on the `root_dir`.
jdtls.start_or_attach(config)

I am on Arch linux, neovim 0.9.4 and vscode-java-test and java-debug are installed as well.

Furthermore, I get these log messages:

[START][2023-11-10 08:43:37] LSP logging initiated
[ERROR][2023-11-10 08:43:37] .../vim/lsp/rpc.lua:734	"rpc"	"jdtls"	"stderr"	"WARNING: Using incubator modules: jdk.incubator.vector\n"
[ERROR][2023-11-10 08:43:37] .../vim/lsp/rpc.lua:734	"rpc"	"jdtls"	"stderr"	"Nov 10, 2023 8:43:37 AM org.apache.aries.spifly.BaseActivator log\nINFO: Registered provider ch.qos.logback.classic.servlet.LogbackServletContainerInitializer of service jakarta.servlet.ServletContainerInitializer in bundle ch.qos.logback.classic\n"
[ERROR][2023-11-10 08:43:37] .../vim/lsp/rpc.lua:734	"rpc"	"jdtls"	"stderr"	"Nov 10, 2023 8:43:37 AM org.apache.aries.spifly.BaseActivator log\nINFO: Registered provider ch.qos.logback.classic.spi.LogbackServiceProvider of service org.slf4j.spi.SLF4JServiceProvider in bundle ch.qos.logback.classic\n"
[ERROR][2023-11-10 08:43:39] ...lsp/handlers.lua:535	"Nov 10, 2023, 8:43:39 AM Empty bundle location"
[WARN][2023-11-10 08:43:47] ...lsp/handlers.lua:137	"The language server jdtls triggers a registerCapability handler despite dynamicRegistration set to false. Report upstream, this warning is harmless"
[ERROR][2023-11-10 08:43:48] ...lsp/handlers.lua:535	"Nov 10, 2023, 8:43:48 AM Command _java.reloadBundles.command not supported on client"

[mrdgo]

Solved the issue. I installed java-21 as well. Despite the message ".../java-21-openjdk is not a valid java home".

[wnyao]

Hi, I'm new to java with terminal. I'm facing a similar issue but with String. Openjdk were installed using homebrew, using jenv with openjdk64-22.0.2 globally. Any help or guidance will be very much appreciated.

Problem

String cannot be resolved to a type [16777218]

Config

-- REFERENCE https://sookocheff.com/post/vim/neovim-java-ide/
local home = os.getenv('HOME')
local jdtls = require('jdtls')

-- File types that signify a Java project's root directory. This will be
-- used by eclipse to determine what constitutes a workspace
local root_dir = require('jdtls.setup').find_root({'gradlew', 'mvnw', '.git'})

-- eclipse.jdt.ls stores project specific data within a folder. If you are working
-- with multiple different projects, each project must use a dedicated data directory.
-- This variable is used to configure eclipse to use the directory name of the
-- current project found using the root_marker as the folder for project specific data.
local workspace_folder = home .. "/.local/share/eclipse/" .. vim.fn.fnamemodify(root_dir, ":p:h:t")

-- Helper function for creating keymaps
function nnoremap(rhs, lhs, bufopts, desc)
  bufopts.desc = desc
  vim.keymap.set("n", rhs, lhs, bufopts)
end

-- The on_attach function is used to set key maps after the language server
-- attaches to the current buffer
local on_attach = function(client, bufnr)
  -- Regular Neovim LSP client keymappings
  local bufopts = { noremap=true, silent=true, buffer=bufnr }
  nnoremap('gD', vim.lsp.buf.declaration, bufopts, "Go to declaration")
  nnoremap('gd', vim.lsp.buf.definition, bufopts, "Go to definition")
  nnoremap('gi', vim.lsp.buf.implementation, bufopts, "Go to implementation")
  nnoremap('K', vim.lsp.buf.hover, bufopts, "Hover text")
  nnoremap('<C-k>', vim.lsp.buf.signature_help, bufopts, "Show signature")
  nnoremap('<space>wa', vim.lsp.buf.add_workspace_folder, bufopts, "Add workspace folder")
  nnoremap('<space>wr', vim.lsp.buf.remove_workspace_folder, bufopts, "Remove workspace folder")
  nnoremap('<space>wl', function()
    print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
  end, bufopts, "List workspace folders")
  nnoremap('<space>D', vim.lsp.buf.type_definition, bufopts, "Go to type definition")
  nnoremap('<space>rn', vim.lsp.buf.rename, bufopts, "Rename")
  nnoremap('<space>ca', vim.lsp.buf.code_action, bufopts, "Code actions")
  vim.keymap.set('v', "<space>ca", "<ESC><CMD>lua vim.lsp.buf.range_code_action()<CR>",
    { noremap=true, silent=true, buffer=bufnr, desc = "Code actions" })
  nnoremap('<space>f', function() vim.lsp.buf.format { async = true } end, bufopts, "Format file")

  -- Java extensions provided by jdtls
  nnoremap("<C-o>", jdtls.organize_imports, bufopts, "Organize imports")
  nnoremap("<space>ev", jdtls.extract_variable, bufopts, "Extract variable")
  nnoremap("<space>ec", jdtls.extract_constant, bufopts, "Extract constant")
  vim.keymap.set('v', "<space>em", [[<ESC><CMD>lua require('jdtls').extract_method(true)<CR>]],
    { noremap=true, silent=true, buffer=bufnr, desc = "Extract method" })
end

local config = {
  flags = {
    debounce_text_changes = 80,
  },
  on_attach = on_attach,  -- We pass our on_attach keybindings to the configuration map
  root_dir = root_dir, -- Set the root directory to our found root_marker
  -- Here you can configure eclipse.jdt.ls specific settings
  -- These are defined by the eclipse.jdt.ls project and will be passed to eclipse when starting.
  -- 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 = {
      format = {
        settings = {
          -- Use Google Java style guidelines for formatting
          -- To use, make sure to download the file from https://github.com/google/styleguide/blob/gh-pages/eclipse-java-google-style.xml
          -- and place it in the ~/.local/share/eclipse directory
          url = "~/.local/share/eclipse/eclipse-java-google-style.xml",
          profile = "GoogleStyle",
        },
      },
      signatureHelp = { enabled = true },
      contentProvider = { preferred = 'fernflower' },  -- Use fernflower to decompile library code
      -- Specify any completion options
      completion = {
        favoriteStaticMembers = {
          "org.hamcrest.MatcherAssert.assertThat",
          "org.hamcrest.Matchers.*",
          "org.hamcrest.CoreMatchers.*",
          "org.junit.jupiter.api.Assertions.*",
          "java.util.Objects.requireNonNull",
          "java.util.Objects.requireNonNullElse",
          "org.mockito.Mockito.*"
        },
        filteredTypes = {
          "com.sun.*",
          "io.micrometer.shaded.*",
          "java.awt.*",
          "jdk.*", 
          "sun.*",
        },
      },
      -- Specify any options for organizing imports
      sources = {
        organizeImports = {
          starThreshold = 9999;
          staticStarThreshold = 9999;
        },
      },
      -- How code generation should act
      codeGeneration = {
        toString = {
          template = "${object.className}{${member.name()}=${member.value}, ${otherMembers}}"
        },
        hashCodeEquals = {
          useJava7Objects = true,
        },
        useBlocks = true,
      },
      -- If you are developing in projects with different Java versions, you need
      -- to tell eclipse.jdt.ls to use the location of the JDK for your Java version
      -- See https://github.com/eclipse/eclipse.jdt.ls/wiki/Running-the-JAVA-LS-server-from-the-command-line#initialize-request
      -- And search for `interface RuntimeOption`
      -- The `name` is NOT arbitrary, but must match one of the elements from `enum ExecutionEnvironment` in the link above
      configuration = {
        runtimes = {
          -- {
          --   name = "JavaSE-17",
          --   path = "/opt/homebrew/opt/openjdk@17",
          -- },
          -- {
          --   name = "JavaSE-21",
          --   path = "/opt/homebrew/opt/openjdk@21",
          -- },
          {
            name = "JavaSE-22",
            path = "/opt/homebrew/opt/openjdk",
          },
        }
      }
    }
  },
  -- cmd is the command that starts the language server. Whatever is placed
  -- here is what is passed to the command line to execute jdtls.
  -- Note that eclipse.jdt.ls must be started with a Java version of 17 or higher
  -- See: https://github.com/eclipse/eclipse.jdt.ls#running-from-the-command-line
  -- for the full list of options
  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',
    '-Xmx4g',
    '--add-modules=ALL-SYSTEM',
    '--add-opens', 'java.base/java.util=ALL-UNNAMED',
    '--add-opens', 'java.base/java.lang=ALL-UNNAMED',
    -- If you use lombok, download the lombok jar and place it in ~/.local/share/eclipse
    -- '-javaagent:' .. home .. '/.local/share/eclipse/lombok.jar',

    -- The jar file is located where jdtls was installed. This will need to be updated
    -- to the location where you installed jdtls
    '-jar', vim.fn.glob('/opt/homebrew/Cellar/jdtls/1.39.0/libexec/plugins/org.eclipse.equinox.launcher_*.jar'),

    -- The configuration for jdtls is also placed where jdtls was installed. This will
    -- need to be updated depending on your environment
    '-configuration', '/opt/homebrew/Cellar/jdtls/1.39.0/libexec/config_mac_arm',

    -- Use the workspace_folder defined above to store data for this project
    '-data', workspace_folder,
  },
}

-- Finally, start jdtls. This will run the language server using the configuration we specified,
-- setup the keymappings, and attach the LSP client to the current buffer
jdtls.start_or_attach(config)