An error thrown when the user requests an IonReader to parse a scalar value that exceeds the reader's configured maximum buffer size. This is never thrown from IonReader#next(); oversized values encountered during next() are skipped. This may be thrown from any IonReader `*value()` method, but only when a maximum buffer size is specified, and only when incremental reading is disabled. When incremental reading is enabled, all oversized values will be detected during `IonReader.next()`, as calling that method at the top level causes the reader to attempt to buffer the entire top-level value. This custom exception type exists because several IonReader `*value()` interface methods return primitives, leaving no way to alert the user to failure. This exception is recoverable; after catching this exception, the user may call `IonReader.next()` to position the reader on the next value in the stream and continue processing.