Listening for transport dt_socket at address: 5005

return {
    "mfussenegger/nvim-dap",
  config = function()
      local dap = require("dap")


      dap.configurations.java = {
          {
              type = "java",
              request = "attach",
              name = "Attach to Gradle bootRun",
              hostName = "127.0.0.1",
              port = 5005,
          },
      }
  end,
}

Error executing vim.schedule lua callback: ...er/.local/share/nvim/lazy/nvim-java/lua/async/runner.lua:34: unhandled error .../.local/share/nvim/lazy/nvim-java/lua/java-dap/setup.lua:47: To enrich the config, mainClass should already be present
stack traceback:
        [C]: in function 'error'
        ...er/.local/share/nvim/lazy/nvim-java/lua/async/runner.lua:34: in function 'callback'
        ...lazy/nvim-java/lua/java-core/ls/clients/jdtls-client.lua:73: in function 'handler'
        /opt/nvim/share/nvim/runtime/lua/vim/lsp/client.lua:682: in function ''
        vim/_editor.lua: in function <vim/_editor.lua:0>