> For the complete documentation index, see [llms.txt](https://trillo.gitbook.io/trillo-workbench-lessons/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trillo.gitbook.io/trillo-workbench-lessons/appendixes/map-list-and-tree.md).

# Map, List and Tree

Trillo Workbench uses json objects, lists of json objects and nested json objects. In Java they correspond to the following Java collection interfaces.

| JSON                         | Java Class                                                        |
| ---------------------------- | ----------------------------------------------------------------- |
| A json object                | Map                                                               |
| A list of json object        | List of Maps                                                      |
| A node of tree               | A Map containing nested Maps and Lists                            |
| A tree (with multiple nodes) | A List of Maps, each Map further containing nested Maps and Lists |