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Most of the remainder of this document illustrates the use of the Sleepycat Java Collections API by presenting a tutorial that describes usage of the API. This tutorial builds a shipment database, a familiar example from classic database texts.
The examples illustrate the following concepts of the Sleepycat Java Collections API:
Object-to-data bindings
The database environment
Databases that contain key/value records
Secondary index databases that contain index keys
Java collections for accessing databases and indices
Transactions used to commit or undo database changes
The examples build on each other, but at the same time the source code for each example stands alone.
The shipment database consists of three database stores: the part store, the supplier store, and the shipment store. Each store contains a number of records, and each record consists of a key and a value.
Store | Key | Value |
---|---|---|
Part | Part Number | Name, Color, Weight, City |
Supplier | Supplier Number | Name, Status, City |
Shipment | Part Number, Supplier Number | Quantity |
In the example programs, Java classes containing the fields above are defined for the key and value of each store: PartKey, PartData, SupplierKey, SupplierData, ShipmentKey and ShipmentData. In addition, because the Part's Weight field is itself composed of two fields — the weight value and the unit of measure — it is represented by a separate Weight class. These classes will be defined in the first example program.
In general the Sleepycat Java Collections API uses bindings to describe how Java objects are stored. A binding defines the stored data syntax and the mapping between a Java object and the stored data. The example programs show how to create different types of bindings, and explains the characteristics of each type.
The following tables show the record values that are used in all the example programs in the tutorial.
Number | Name | Color | Weight | City |
---|---|---|---|---|
P1 | Nut | Red | 12.0 grams | London |
P2 | Bolt | Green | 17.0 grams | Paris |
P3 | Screw | Blue | 17.0 grams | Rome |
P4 | Screw | Red | 14.0 grams | London |
P5 | Cam | Blue | 12.0 grams | Paris |
P6 | Cog | Red | 19.0 grams | London |
Number | Name | Status | City |
---|---|---|---|
S1 | Smith | 20 | London |
S2 | Jones | 10 | Paris |
S3 | Blake | 30 | Paris |
S4 | Clark | 20 | London |
S5 | Adams | 30 | Athens |
Part Number | Supplier Number | Quantity |
---|---|---|
P1 | S1 | 300 |
P1 | S2 | 300 |
P2 | S1 | 200 |
P2 | S2 | 400 |
P2 | S3 | 200 |
P2 | S4 | 200 |
P3 | S1 | 400 |
P4 | S1 | 200 |
P4 | S4 | 300 |
P5 | S1 | 100 |
P5 | S4 | 400 |
P6 | S1 | 100 |