Using Sorted Collections
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## Using Sorted Collections

In general, no changes to the prior example are necessary to use collections having tuple keys. Iteration of elements in a stored collection will be ordered by the sort order of the tuples.

In addition to using the tuple format, the DatabaseType.BTREE access method must be used when creating the database. DatabaseType.BTREE is used for the databases in all examples. The DatabaseType.HASH access method does not support sorted keys.

Although not shown in the example, all methods of the SortedMap and SortedSet interfaces may be used with sorted collections. For example, submaps and subsets may be created.

The output of the example program shows that records are sorted by key value.

    Adding Suppliers
    Adding Parts
    Adding Shipments

    --- Parts ---
    Part: number=P1 name=Nut color=Red weight=[12.0 grams] city=London
    Part: number=P2 name=Bolt color=Green weight=[17.0 grams] city=Paris
    Part: number=P3 name=Screw color=Blue weight=[17.0 grams] city=Rome
    Part: number=P4 name=Screw color=Red weight=[14.0 grams] city=London
    Part: number=P5 name=Cam color=Blue weight=[12.0 grams] city=Paris
    Part: number=P6 name=Cog color=Red weight=[19.0 grams] city=London

    --- Suppliers ---
    Supplier: number=S1 name=Smith status=20 city=London
    Supplier: number=S2 name=Jones status=10 city=Paris
    Supplier: number=S3 name=Blake status=30 city=Paris
    Supplier: number=S4 name=Clark status=20 city=London
    Supplier: number=S5 name=Adams status=30 city=Athens

    --- Suppliers for City Paris ---
    Supplier: number=S2 name=Jones status=10 city=Paris
    Supplier: number=S3 name=Blake status=30 city=Paris

    --- Shipments ---
    Shipment: part=P1 supplier=S1 quantity=300
    Shipment: part=P1 supplier=S2 quantity=300
    Shipment: part=P2 supplier=S1 quantity=200
    Shipment: part=P2 supplier=S2 quantity=400
    Shipment: part=P2 supplier=S3 quantity=200
    Shipment: part=P2 supplier=S4 quantity=200
    Shipment: part=P3 supplier=S1 quantity=400
    Shipment: part=P4 supplier=S1 quantity=200
    Shipment: part=P4 supplier=S4 quantity=300
    Shipment: part=P5 supplier=S1 quantity=100
    Shipment: part=P5 supplier=S4 quantity=400
    Shipment: part=P6 supplier=S1 quantity=100

    --- Shipments for Part P1 ---
    Shipment: part=P1 supplier=S1 quantity=300
    Shipment: part=P1 supplier=S2 quantity=300

    --- Shipments for Supplier S1 ---
    Shipment: part=P1 supplier=S1 quantity=300
    Shipment: part=P2 supplier=S1 quantity=200
    Shipment: part=P3 supplier=S1 quantity=400
    Shipment: part=P4 supplier=S1 quantity=200
    Shipment: part=P5 supplier=S1 quantity=100
    Shipment: part=P6 supplier=S1 quantity=100

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