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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