opennlp.tools.ml.model (Apache OpenNLP Tools 1.9.5 API)
Date: 2026-06-18

# Package opennlp.tools.ml.model

- Interface Summary
  Interface | Description
  --- | ---
  DataIndexer | Object which compresses events in memory and performs feature selection.
  DataReader |
  MaxentModel | Interface for maximum entropy models.
  Prior | This interface allows one to implement a prior distribution for use in maximum entropy model training.
  SequenceClassificationModel<T> | A classification model that can label an input sequence.
  SequenceStream | Interface for streams of sequences used to train sequence models.

- Class Summary
  Class | Description
  --- | ---
  AbstractDataIndexer | Abstract class for collecting event and context counts used in training.
  AbstractModel |
  AbstractModelReader |
  AbstractModelWriter |
  BinaryFileDataReader |
  ComparableEvent | A maxent event representation which we can use to sort based on the predicates indexes contained in the events.
  ComparablePredicate | A maxent predicate representation which we can use to sort based on the outcomes.
  Context | Class which associates a real valued parameter or expected value with a particular contextual predicate or feature.
  DataIndexerFactory |
  DynamicEvalParameters |
  EvalParameters | This class encapsulates the varibales used in producing probabilities from a model and facilitaes passing these variables to the eval method.
  Event | The context of a decision point during training.
  FileEventStream | Class for using a file of events as an event stream.
  GenericModelReader |
  GenericModelWriter |
  HashSumEventStream |
  MutableContext | Class used to store parameters or expected values associated with this context which can be updated or assigned.
  ObjectDataReader |
  OnePassDataIndexer | An indexer for maxent model data which handles cutoffs for uncommon contextual predicates and provides a unique integer index for each of the predicates.
  OnePassRealValueDataIndexer | An indexer for maxent model data which handles cutoffs for uncommon contextual predicates and provides a unique integer index for each of the predicates and maintains event values.
  PlainTextFileDataReader |
  RealValueFileEventStream |
  Sequence<T> | Class which models a sequence.
  SequenceStreamEventStream | Class which turns a sequence stream into an event stream.
  TwoPassDataIndexer | Collecting event and context counts by making two passes over the events.
  UniformPrior | Provide a maximum entropy model with a uniform prior.

- Enum Summary
  Enum | Description
  --- | ---
  AbstractModel.ModelType |

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