com.newrelic.agent

Class TransactionActivity

java.lang.Object

com.newrelic.agent.TransactionActivity

public class TransactionActivity
extends java.lang.Object

This class tracks the state of a single asynchronous activity within a transaction. An instance of this class may be associated with e.g. a thread, the execution of a task on pool thread, or the execution of a "coroutine" on a thread.

This class is not threadsafe, but is typically referenced by two distinct threads during its lifetime. First, it holds state for its associated thread (or task, etc.) until its root tracer completes. It may then be queued (indirectly through its owning transaction) for harvest, during which it is referenced by the harvest thread. These two usages never overlap in time. Memory visibility is assured because the transaction will pass through a synchronized object (e.g. atomic or concurrent collection) that has the effect of inserting a full barrier between the async activity's last write and the harvest thread's first read.

Field Summary

Fields

Modifier and Type	Field and Description
static int	NOT_REPORTED

Constructor Summary

Constructors

Constructor and Description
TransactionActivity() The public constructor may be used only for test purposes.

Method Summary

Modifier and Type	Method and Description
void	addTracer(Tracer tracer)
Tracer	addTracerToStack(Tracer tracer) Copies a tracer to the call stack.
boolean	canCreateTransactionSegment() Return true if the tracer being created is allowed to create a new segment.
boolean	checkTracerStart() Optimized tracer start call.
static void	clear() Clear the TransactionActivity from the thread local that holds it.
static TransactionActivity	create(Transaction transaction, int id)
static TransactionActivity	createWithoutHolder(Transaction transaction, int id, java.lang.String asyncContext) Creates a TransactionActivity.
void	finishFlyweightTracer(com.newrelic.agent.bridge.TracedMethod parent, long startInNanos, long finishInNanos, java.lang.String className, java.lang.String methodName, java.lang.String methodDesc, java.lang.String metricName, java.lang.String[] rollupMetricNames)
static TransactionActivity	get()
java.lang.String	getAsyncContext()
Tracer	getLastTracer() Get the last tracer on the call stack, or null if the call stack is empty.
Tracer	getRootTracer()
Segment	getSegment()
long	getThreadId()
long	getTotalCpuTime() Returns the total cpu time in nanoseconds;
java.util.List<Tracer>	getTracers() Return the current state of the tracer stack for this activity.
Transaction	getTransaction()
TransactionCache	getTransactionCache() Get a cache to store objects for the life of the transaction.
TransactionStats	getTransactionStats()
int	hashCode()
boolean	isFinished()
boolean	isIgnored()
boolean	isLeaf() Return true if the tracer at the top of tracer stack is a flyweight tracer (leaf by default) or a leaf tracer.
boolean	isNotInThreadLocal()
boolean	isStarted()
boolean	isTracerStartLocked() Test the tracer start lock.
void	lockTracerStart() The tracer start lock is designed to prevent tracers from being created during the creation of another tracer.
void	markAsResponseSender()
void	recordCpu()
static void	set(TransactionActivity txa) Jam the argument into the thread local that holds it.
void	setAsyncContext(java.lang.String asyncContext) set the async context associated with this transaction activity.
void	setSegment(Segment segment)
void	setToIgnore()
void	setTotalCpuTime(long totalCpuTimeInNanos)
void	startAsyncActivity(Transaction transaction, int activityId, Tracer parentTracer)
com.newrelic.agent.bridge.TracedMethod	startFlyweightTracer()
void	tracerFinished(Tracer tracer, int opcode) Pop the finished tracer off the call stack.
Tracer	tracerStarted(Tracer tracer) Adds a tracer to the call stack.
void	unlockTracerStart() Release the tracer start lock.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

NOT_REPORTED

public static final int NOT_REPORTED

See Also:

Constant Field Values

Constructor Detail

TransactionActivity

public TransactionActivity()

The public constructor may be used only for test purposes.

Method Detail

clear

public static void clear()

Clear the TransactionActivity from the thread local that holds it. This is a "dangerous" interface that is required for instrumentation in which the transaction+activity are multiplexed on a thread (e.g. "coroutine" or "continuation" mechanisms such as Javaflow or the async servlet interface).

set

public static void set(TransactionActivity txa)

Jam the argument into the thread local that holds it. This is a "dangerous" interface that is required for instrumentation in which the transaction+activity are multiplexed on a thread (e.g. "coroutine" or "continuation" mechanisms such as Javaflow or the async servlet interface).

Parameters:

txa - the new value to make current

get

public static TransactionActivity get()

create

public static TransactionActivity create(Transaction transaction,
                                         int id)

createWithoutHolder

public static TransactionActivity createWithoutHolder(Transaction transaction,
                                                      int id,
                                                      java.lang.String asyncContext)

Creates a TransactionActivity. Does not set the activity in the activityHolder; so it will not override whatever activity is currently in progress.

Parameters:

transaction - parent transaction

id - ID of the activity

asyncContext - name of async context; since external async spans multiple threads, this is typically the thread name that this is running on.

Returns:

activity

canCreateTransactionSegment

public boolean canCreateTransactionSegment()

Return true if the tracer being created is allowed to create a new segment.

Returns:

true if the tracer being created is allowed to create a new segment.

markAsResponseSender

public void markAsResponseSender()

getThreadId

public long getThreadId()

getAsyncContext

public java.lang.String getAsyncContext()

Returns:

the async context associated with this transaction activity. This shows up on transaction traces.

setAsyncContext

public void setAsyncContext(java.lang.String asyncContext)

set the async context associated with this transaction activity. This shows up on transaction traces.

getTransactionStats

public TransactionStats getTransactionStats()

getTracers

public java.util.List<Tracer> getTracers()

Return the current state of the tracer stack for this activity.

Returns:

the current state of the tracer stack for this activity.

getTotalCpuTime

public long getTotalCpuTime()

Returns the total cpu time in nanoseconds;

isNotInThreadLocal

public boolean isNotInThreadLocal()

setTotalCpuTime

public void setTotalCpuTime(long totalCpuTimeInNanos)

setToIgnore

public void setToIgnore()

isIgnored

public boolean isIgnored()

tracerStarted

public Tracer tracerStarted(Tracer tracer)

Adds a tracer to the call stack.

Parameters:

tracer -

addTracerToStack

public Tracer addTracerToStack(Tracer tracer)

Copies a tracer to the call stack.

Parameters:

tracer -

Returns:

The tracer if it was successfully added to the stack or null if it wasn't

tracerFinished

public void tracerFinished(Tracer tracer,
                           int opcode)

Pop the finished tracer off the call stack.

isStarted

public boolean isStarted()

isFinished

public boolean isFinished()

isLeaf

public boolean isLeaf()

Return true if the tracer at the top of tracer stack is a flyweight tracer (leaf by default) or a leaf tracer.

Returns:

true if the tracer at the top of tracer stack is a flyweight tracer (leaf by default) or a leaf tracer.

recordCpu

public void recordCpu()

addTracer

public void addTracer(Tracer tracer)

setSegment

public void setSegment(Segment segment)

getSegment

public Segment getSegment()

lockTracerStart

public void lockTracerStart()

The tracer start lock is designed to prevent tracers from being created during the creation of another tracer. Acquire the lock. Note: fast path callers should use checkTracerStart() to reduce the number of method calls to this object.

unlockTracerStart

public void unlockTracerStart()

Release the tracer start lock.

isTracerStartLocked

public boolean isTracerStartLocked()

Test the tracer start lock.

Returns:

True if the lock is held. The "lock" is designed to prevent reentrancy by the thread already holding it, so of course it is implemented as a non-reentrant lock.

checkTracerStart

public boolean checkTracerStart()

Optimized tracer start call. Checks several conditions and if all conditions hold then return true. Note: if a transaction is over its segment limit, we still create tracers, but don't start them. So we don't check the segment limit here.

Returns:

True if can create a tracer on this thread at this time else false. If the return value is true, the tracerStartLock is held and the caller is responsible for later calling unlockTracerStart().

getLastTracer

public Tracer getLastTracer()

Get the last tracer on the call stack, or null if the call stack is empty.

startFlyweightTracer

public com.newrelic.agent.bridge.TracedMethod startFlyweightTracer()

finishFlyweightTracer

public void finishFlyweightTracer(com.newrelic.agent.bridge.TracedMethod parent,
                                  long startInNanos,
                                  long finishInNanos,
                                  java.lang.String className,
                                  java.lang.String methodName,
                                  java.lang.String methodDesc,
                                  java.lang.String metricName,
                                  java.lang.String[] rollupMetricNames)

startAsyncActivity

public void startAsyncActivity(Transaction transaction,
                               int activityId,
                               Tracer parentTracer)

getRootTracer

public Tracer getRootTracer()

getTransactionCache

public TransactionCache getTransactionCache()

Get a cache to store objects for the life of the transaction.

getTransaction

public Transaction getTransaction()

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object