androidx.tracing

Interfaces

AbstractTraceDriver.Factory

Provides the instance of AbstractTraceDriver that can be used for in-process-tracing.
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Counter

Handle for emitting Long or Counter counter event updates into a trace.
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PropagationToken

A token representing state carried forward for context propagation.
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Classes

AbstractTraceDriver

The entry point for the tracing API.
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AbstractTraceSink

Receives PooledTracePacketArrays from Tracks and asynchronously serializes them to a file or buffer, depending on implementation.
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AtomicBoolean
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AtomicInteger
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AtomicLong
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AttributeEntry

TraceEvents can contain trace attributes that apply to the entire trace.
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EventMetadata

Makes it possible to associate debug metadata & categories to a TraceEvent.
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EventMetadataCloseable

A holder for a EventMetadata and the AutoCloseable.
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Frame

TraceEvents can additionally contain callstack information.
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MetadataEntry

TraceEvents can contain metadata.
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PlatformThreadContextElement

We use the PlatformThreadContextElement construct to know when a coroutine has suspended, and about to resume on a Thread.
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Poolable

Represents an object that can be reused using a Pool.
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PooledTracePacketArray
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TraceAttributes

Makes it possible to associate key value pairs to be attached to a trace to provide additional context about any facet of the trace.
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TraceEvent

Mutable in-memory only representation a trace event, such as a slice start, slice end, or counter update.
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Tracer

A Tracer is the entry point for all Tracing APIs.
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TrackDescriptor

Low level representation of a Track, written once to the Trace.
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Objects

PropagationUnsupportedToken

The PropagationToken instance that should be returned when context propagation is unsupported by the underlying Tracer.
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Trace
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Annotations

DelicateTracingApi

Represents an API surface that is typically only useful for custom implementations of a AbstractTraceSink or a Track.
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ExperimentalContextPropagation

Represents an API surface that is typically only useful for custom context propagation.
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Type aliases

AtomicBoolean
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AtomicInteger
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AtomicLong
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Top-level functions summary

Long
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inline T
<T : Any?> trace(label: String, block: () -> T)

Wrap the specified block in calls to Trace.beginSection (with the supplied label) and Trace.endSection.
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inline T
<T : Any?> trace(lazyLabel: () -> String, block: () -> T)

Wrap the specified block in calls to Trace.beginSection (with a lazy-computed lazyLabel, only if tracing is enabled - Trace.isEnabled) and Trace.endSection.
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inline T
<T : Any?> traceAsync(
    lazyMethodName: () -> String,
    lazyCookie: () -> Int,
    block: () -> T
)

Wrap the specified block in calls to Trace.beginAsyncSection and Trace.endAsyncSection, with a lazy-computed lazyMethodName and lazyCookie, only if tracing is enabled - Trace.isEnabled.
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suspend inline T
<T : Any?> traceAsync(
    methodName: String,
    cookie: Int,
    crossinline block: suspend () -> T
)

Wrap the specified block in calls to Trace.beginAsyncSection (with the supplied methodName and cookie) and Trace.endAsyncSection.
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Extension functions summary

Nothing
Tracer.recordExceptionAndThrow(
    category: String,
    name: String,
    throwable: Throwable
)

Records an exceptional event in a trace.
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Top-level functions

nanoTime

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fun nanoTime(): Long

trace

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inline fun <T : Any?> trace(label: String, block: () -> T): T

Wrap the specified block in calls to Trace.beginSection (with the supplied label) and Trace.endSection.

Parameters
label: String

A name of the code section to appear in the trace.
block: () -> T

A block of code which is being traced.

trace

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inline fun <T : Any?> trace(lazyLabel: () -> String, block: () -> T): T

Wrap the specified block in calls to Trace.beginSection (with a lazy-computed lazyLabel, only if tracing is enabled - Trace.isEnabled) and Trace.endSection.

This variant allows you to build a dynamic label, but only when tracing is enabled, avoiding the cost of String construction otherwise.

Parameters
lazyLabel: () -> String

A name of the code section to appear in the trace, computed lazily if needed.
block: () -> T

A block of code which is being traced.

traceAsync

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inline fun <T : Any?> traceAsync(
    lazyMethodName: () -> String,
    lazyCookie: () -> Int,
    block: () -> T
): T

Wrap the specified block in calls to Trace.beginAsyncSection and Trace.endAsyncSection, with a lazy-computed lazyMethodName and lazyCookie, only if tracing is enabled - Trace.isEnabled.

Parameters
lazyMethodName: () -> String

The method name to appear in the trace, computed lazily if needed.
lazyCookie: () -> Int

Unique identifier for distinguishing simultaneous events, computed lazily if needed.
block: () -> T

a code block to be wrapped between Trace.beginAsyncSection and Trace.endAsyncSection.

traceAsync

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suspend inline fun <T : Any?> traceAsync(
    methodName: String,
    cookie: Int,
    crossinline block: suspend () -> T
): T

Wrap the specified block in calls to Trace.beginAsyncSection (with the supplied methodName and cookie) and Trace.endAsyncSection.

Parameters
methodName: String

The method name to appear in the trace.
cookie: Int

Unique identifier for distinguishing simultaneous events
crossinline block: suspend () -> T

A code block to be wrapped between Trace.beginAsyncSection and Trace.endAsyncSection.

Extension functions

Tracer.recordExceptionAndThrow

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fun Tracer.recordExceptionAndThrow(
    category: String,
    name: String,
    throwable: Throwable
): Nothing

Records an exceptional event in a trace. This method rethrows the throwable after having extracting all metadata worth tracing.

Parameters
category: String

The String category. It's useful to categorize TraceEvents, so that they can be filtered if necessary using the appropriate trace configuration.
name: String

The name of the trace section.
throwable: Throwable

The exception thrown by a block of code.