POF objects are indexed so it is
possible to quickly traverse/navigate the binary (serialized form) to a
specific element for extraction or updating using the indices without
de-serializing the entire binary. Out of the box, coherence provides SimplePofPath
class that can navigate a POF value based on integer indices. In the simplest
form, all you need to do is to provide the index of the attribute that you want
to extract/update. Some of the best practices that are coming to my mind are as
under:
- Order your reads and writes: start with the lowest index value in the serialization routine and finish with the highest. When deserializing a value, perform reads in the same order as writes.
- Use the smallest possible integer for indexing the objects
- Non-contiguous indexes are acceptable but must be read/written sequentially.
- For subclasses reserve index ranges: index's are cumulative across derived types. As such, each derived type must be aware of the POF index range reserved by its super class.
- Do not re-purpose indexes: to support Evolvable, it's imperative that indexes of attributes are not re-purposed across class revisions.
- Label each of the index for the attribute
- The most frequently used attribute in the Filter(s) and Extractor(s) should be assigned lowest index.
- Enable POF Object reference if the objects have circular/nested references (feature available in 3.7.1 + only)
