default Object getCachedObject() {
    return getObject();
  }
The same as calling getObject() but may also cache the result and future calls
of this method will return the cached object instead of recomputing it.
Implementors that do not want to support a cache can just use the default implementation
which simply calls getObject().

@throws PdxSerializationException if the instance could not be deserialized
geode-core/src/main/java/org/apache/geode/pdx/internal/InternalPdxInstance.java