Implementation:Microsoft Onnxruntime OrtHardwareDevice

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

Domains

• Machine Learning Runtime
• Hardware Device Enumeration

Overview

OrtHardwareDevice is a final class representing hardware device information for a specific device in the ONNX Runtime system. It contains the device type (CPU, GPU, or NPU), vendor identification, device ID, and metadata. It also contains the OrtHardwareDeviceType inner enum. Instances are accessed through OrtEpDevice.getDevice().

Description

The class wraps a native handle and eagerly extracts:

• type: An OrtHardwareDeviceType enum (CPU, GPU, or NPU).
• vendorId: An integer vendor identifier.
• vendor: A string vendor name.
• deviceId: An integer device identifier.
• metadata: An unmodifiable Map<String, String> of device metadata.

The OrtHardwareDeviceType enum defines CPU (0), GPU (1), and NPU (2) with mapFromInt for native conversion (defaults to CPU for unknown values).

Code Reference

Source Location

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

Signature

public final class OrtHardwareDevice {
    public OrtHardwareDeviceType getType();
    public int getVendorId();
    public int getDeviceId();
    public String getVendor();
    public Map<String, String> getMetadata();

    public enum OrtHardwareDeviceType {
        CPU(0), GPU(1), NPU(2);
        public int getValue();
        public static OrtHardwareDeviceType mapFromInt(int deviceType);
    }
}

Import

import ai.onnxruntime.OrtHardwareDevice;
import ai.onnxruntime.OrtHardwareDevice.OrtHardwareDeviceType;

I/O Contract

Inputs

Name	Type	Description
nativeHandle	long	Pointer to the native hardware device struct (internal)

Outputs

Name	Type	Description
getType()	OrtHardwareDeviceType	CPU, GPU, or NPU
getVendorId()	int	Numeric vendor identifier
getVendor()	String	Vendor name string
getDeviceId()	int	Numeric device identifier
getMetadata()	Map<String, String>	Device metadata key-value pairs

Usage Examples

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

OrtEnvironment env = OrtEnvironment.getEnvironment();
List<OrtEpDevice> epDevices = env.getEpDevices();

for (OrtEpDevice epDev : epDevices) {
    OrtHardwareDevice device = epDev.getDevice();
    System.out.println("Device type: " + device.getType());
    System.out.println("Vendor: " + device.getVendor() + " (ID: " + device.getVendorId() + ")");
    System.out.println("Device ID: " + device.getDeviceId());
    System.out.println("Metadata: " + device.getMetadata());
}

Related Pages

• OrtEpDevice.java - EP device tuple containing OrtHardwareDevice
• OrtEnvironment.java - Provides getEpDevices() for device discovery