Accessing Objects Overview

The information in the Repository is a network of objects and relationships. For example, consider a sample tool that stores information about bugs, persons who report those bugs, and programs in which those bugs occur. Each person can report many bugs, and each bug can be reported by one person. Each program can have many bugs reported on it, and each bug can apply to one program.

The following figure illustrates some typical data stored by this sample tool. In the figure, each point represents an object and each line represents a relationship between two objects.

The data in the preceding figure shows how you can:

• Move from one object to another by following a particular relationship.

  For example, to learn the file name of the program containing bug 15, follow a particular relationship from bug 15 to the object representing the program, and then retrieve that object's file name property.

• Focus your attention on a collection stored in the Repository by retrieving it directly from the Repository. For example, you can retrieve a collection containing the bugs that Frank has reported.

  The following figure shows this collection.

• Follow a path consisting of multiple relationships by following each individual relationship in turn. For example, while manipulating the object representing Frank, you can move through the Repository's contents to answer the question "On what program did Frank report his first bug?"

  The following figure shows the path from the object representing Frank through the object representing Frank's first reported bug to the object representing the program on which Frank reported that bug.