Implementation:Microsoft Onnxruntime SequenceInfo

Knowledge Sources	Description
Source File	java/src/main/java/ai/onnxruntime/SequenceInfo.java
Repository	Microsoft/onnxruntime

Domains

• Machine Learning Runtime
• Type Metadata

Overview

SequenceInfo describes an OnnxSequence, including its element type and length. It implements the ValueInfo interface and differentiates between sequences of tensors and sequences of maps. The class is constructed internally from JNI and by OrtSession when inspecting model outputs.

Description

The class has four public fields:

• sequenceOfMaps: Boolean indicating whether the sequence contains maps.
• sequenceType: The OnnxJavaType of elements (STRING, INT64, FLOAT, DOUBLE); UNKNOWN if it contains maps.
• mapInfo: A MapInfo describing the map type if sequenceOfMaps is true; null otherwise.
• length: The number of elements (-1 if unknown).

Four constructors exist: 1. Tensor sequence with known type: (int length, OnnxJavaType sequenceType) 2. Tensor sequence from JNI: (int length, int sequenceTypeInt) 3. Map sequence with MapInfo: (int length, MapInfo mapInfo) 4. Map sequence with key/value types: (int length, OnnxJavaType keyType, OnnxJavaType valueType)

The isSequenceOfMaps() method provides a convenience check.

Code Reference

Source Location

// File: java/src/main/java/ai/onnxruntime/SequenceInfo.java
// Package: ai.onnxruntime

Signature

public class SequenceInfo implements ValueInfo {
    public final boolean sequenceOfMaps;
    public final OnnxJavaType sequenceType;
    public final MapInfo mapInfo;
    public final int length;

    public boolean isSequenceOfMaps();
}

Import

import ai.onnxruntime.SequenceInfo;

I/O Contract

Inputs

Name	Type	Description
length	int	Number of elements (-1 if unknown)
sequenceType	OnnxJavaType	Element type for tensor sequences
mapInfo	MapInfo	Map type info for map sequences

Outputs

Name	Type	Description
sequenceOfMaps	boolean	Whether the sequence contains maps
sequenceType	OnnxJavaType	Element type (UNKNOWN for map sequences)
mapInfo	MapInfo	Map type info (null for tensor sequences)
length	int	Element count (-1 if unknown)

Usage Examples

import ai.onnxruntime.*;
import java.util.*;

OrtEnvironment env = OrtEnvironment.getEnvironment();
try (OrtSession session = env.createSession("/path/to/model.onnx")) {
    Map<String, NodeInfo> outputInfo = session.getOutputInfo();
    for (Map.Entry<String, NodeInfo> entry : outputInfo.entrySet()) {
        ValueInfo info = entry.getValue().getInfo();
        if (info instanceof SequenceInfo) {
            SequenceInfo seqInfo = (SequenceInfo) info;
            System.out.println("Output '" + entry.getKey() + "' is a sequence:");
            System.out.println("  Length: " + seqInfo.length);
            if (seqInfo.isSequenceOfMaps()) {
                System.out.println("  Contains maps: " + seqInfo.mapInfo);
            } else {
                System.out.println("  Element type: " + seqInfo.sequenceType);
            }
        }
    }
}

Related Pages

• OnnxSequence.java - The sequence container described by SequenceInfo
• MapInfo.java - Map type info used in map sequences
• NodeInfo.java - Node information that wraps SequenceInfo