io.praesid.livestats

Class ServiceStats

java.lang.Object

io.praesid.livestats.ServiceStats

public abstract class ServiceStats
extends Object

Method Summary

Modifier and Type	Method and Description
protected abstract void	addTiming(String key, long nanos, long endNanos)
<T> T	collectTiming(String name, java.util.function.Supplier<T> subject) Records the execution time for `subject` at a key based on `name`.
<T> T	collectTiming(String name, java.util.function.Supplier<T> subject, java.util.function.Predicate<T> successful) Records the execution time for `subject` at a key based on `name`.
<T> T	collectTimingWithThrownFailures(String name, java.util.function.Supplier<T> subject, java.util.function.Predicate<Throwable> expected) Records the execution time for `subject` at a key based on `name`.
void	complete(String key, long startNanos) Puts a timing entry of `System.nanoTime() - startNanos` into the stats for `key`.
static void	configure(DecayConfig decayConfig, double... quantiles)
static void	configure(DecayConfig defaultDecayConfig, Map<String,DecayConfig> decayConfigMap, double... quantiles)
static void	configure(double... quantiles)
abstract Stats[]	consume() Consumes a snapshot of the live stats currently collected.
static void	disable()
abstract java.util.stream.Stream<Stats>	get(String... statsNames) Gets a snapshot of the live stats currently collected.
static ServiceStats	instance()
void	put(String key, long nanos) Puts a timing entry of `nanos` into the stats for `key`.
<T> CompletableFuture<T>	timingOnCompletion(String name, java.util.function.Supplier<CompletableFuture<T>> subject) Records the execution time for the future produced by `subject` at a key based on `name`.
<T> CompletableFuture<T>	timingOnCompletion(String name, java.util.function.Supplier<CompletableFuture<T>> subject, java.util.function.Predicate<T> successful) Records the execution time for the future produced by `subject` at a key based on `name`.

Methods inherited from class java.lang.Object

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

Method Detail

put

public void put(String key,
                long nanos)

Puts a timing entry of `nanos` into the stats for `key`.

Parameters:

key - The key to add a timing entry for.

nanos - The number of nanoseconds to record.

complete

public void complete(String key,
                     long startNanos)

Puts a timing entry of `System.nanoTime() - startNanos` into the stats for `key`.

Parameters:

key - The key to add a timing entry for.

startNanos - The System.nanoTime() at which the subject task started.

timingOnCompletion

public <T> CompletableFuture<T> timingOnCompletion(String name,
                                                   java.util.function.Supplier<CompletableFuture<T>> subject)

Records the execution time for the future produced by `subject` at a key based on `name`. The key for the stats is "`name`/success" unless the task throws an exception, then it's "`name`/error".

Type Parameters:

T -

Parameters:

name - The base name used to determine which stats key to store the resulting timing entry.

subject - A supplier which starts the task to be timed.

Returns:

The same future produced by `subject`.

timingOnCompletion

public <T> CompletableFuture<T> timingOnCompletion(String name,
                                                   java.util.function.Supplier<CompletableFuture<T>> subject,
                                                   java.util.function.Predicate<T> successful)

Records the execution time for the future produced by `subject` at a key based on `name`. The key for the stats is "`name`/success" or "`name`/failure" based on the supplied predicate, unless the task throws an exception, then it's "`name`/error".

Type Parameters:

T -

Parameters:

name - The base name used to determine which stats key to store the resulting timing entry.

subject - A supplier which starts the code to be timed.

successful - A predicate on the result of the supplied future to determine whether the task was successful.

Returns:

The same future produced by `subject`.

collectTiming

public <T> T collectTiming(String name,
                           java.util.function.Supplier<T> subject)

Records the execution time for `subject` at a key based on `name`. The key for the stats is "`name`/success" unless the task throws an exception, then it's "`name`/error".

Type Parameters:

T -

Parameters:

name - The base name used to determine which stats key to store the resulting timing entry.

subject - The task to be timed.

Returns:

The same result produced by `subject`.

collectTimingWithThrownFailures

public <T> T collectTimingWithThrownFailures(String name,
                                             java.util.function.Supplier<T> subject,
                                             java.util.function.Predicate<Throwable> expected)

Records the execution time for `subject` at a key based on `name`. The key for the stats is "`name`/success" unless the task throws, then it's "`name`/error" or "`name`/failure" based on the supplied function.

Type Parameters:

T -

Parameters:

name - The base name used to determine which stats key to store the resulting timing entry.

subject - The task to be timed.

expected - A predicate to indicate whether an thrown Throwable is an expected 'failure' or an 'error'.

Returns:

The same result produced by `subject`.

collectTiming

public <T> T collectTiming(String name,
                           java.util.function.Supplier<T> subject,
                           java.util.function.Predicate<T> successful)

Records the execution time for `subject` at a key based on `name`. The key for the stats is "`name`/success" or "`name`/failure" based on the supplied predicate, unless the task throws an exception, then it's "`name`/error".

Type Parameters:

T -

Parameters:

name - The base name used to determine which stats key to store the resulting timing entry.

subject - The task to be timed.

successful - A predicate on the result of the supplied future to determine whether the task was successful.

Returns:

The same result produced by `subject`.

consume

public abstract Stats[] consume()

Consumes a snapshot of the live stats currently collected. Usually, this method makes sense when using non-decaying stats. NOTE: This is a destructive call, the returned stats are the only remaining reference to the collected data.

Returns:

stats snapshots

get

public abstract java.util.stream.Stream<Stats> get(String... statsNames)

Gets a snapshot of the live stats currently collected. Usually, this method makes sense when using decaying stats.

Returns:

stats snapshots

addTiming

protected abstract void addTiming(String key,
                                  long nanos,
                                  long endNanos)

disable

public static void disable()

configure

public static void configure(double... quantiles)

configure

public static void configure(DecayConfig decayConfig,
                             double... quantiles)

configure

public static void configure(DecayConfig defaultDecayConfig,
                             Map<String,DecayConfig> decayConfigMap,
                             double... quantiles)

instance

public static ServiceStats instance()