digraph ClassDiagram {
    // Graph attributes
    graph [
        rankdir="BT",
        splines=ortho,
        fontname="Arial"
    ];
    node [
        fontname="Arial",
        fontsize=10,
        shape=record,
        style=filled,
        fillcolor=lightyellow
    ];
    edge [
        fontname="Arial",
        fontsize=9
    ];

    // --- Clusters for Packages ---
    subgraph cluster_edu_inventorym {
        label="edu.inventorym";
        style=filled;
        color=lightgrey;
        node [style=filled, color=white];

        Api [
            label="{class Api|+ main(String[]): void\l+ callerInterface(): void\l}"
        ];

        App [
            label="{class App|+ main(String[]): void\l- routing(HttpRouting.Builder): void\l}"
        ];

        RpcDeserializer [
            label="{class RpcDeserializer|+ main(String[]): void\l+ mapJsonToObjectList(String, Class<T>): List<T>\l}"
        ];
    }

    subgraph cluster_edu_inventorym_model {
        label="edu.inventorym.model";
        style=filled;
        color=lightgrey;
        node [style=filled, color=white];

        InventoryPiece [
            // Inferred from RpcDeserializer.java
            label="{interface\n«InventoryPiece»|+ getId(): int\l}"
        ];

        Drawing [
            // Inferred from RpcDeserializer.java
            label="{class Drawing|+ getId(): int\l}"
        ];
    }


    // --- Relationships ---

    // Inheritance (Drawing implements InventoryPiece)
    InventoryPiece -> Drawing [
        arrowhead=empty,
        style=dashed,
        label="implements"
    ];

    // Associations (Dependencies)
    RpcDeserializer -> Drawing [
        arrowhead=vee,
        style=dashed,
        label="uses"
    ];

    RpcDeserializer -> InventoryPiece [
        arrowhead=vee,
        style=dashed,
        label="uses"
    ];
}