net.joala.condition.timing

Class DeceleratingWait

java.lang.Object

net.joala.condition.timing.DeceleratingWait

All Implemented Interfaces:

Wait

public class DeceleratingWait
extends Object
implements Wait

A waiter that uses the exponential backoff approach when waiting for a condition. Starting with a minimum wait period, the algorithm waits successively longer on subsequent attempts, increasing the wait time by a small percentage. This allows short waits to be completed quickly while reducing the overhead for repeated checks during long waits.

The expected number of checks grows logarithmically with the wait duration, while the wait duration remains within a constant factor of the actual time until the condition holds true.

Constructor Summary

Constructors

Constructor and Description
DeceleratingWait()
DeceleratingWait(Timeout timeout)
DeceleratingWait(Timeout timeout, double timeoutFactor)
DeceleratingWait(Timeout timeout, double timeoutFactor, WaitFailStrategy failStrategy)
DeceleratingWait(Timeout timeout, WaitFailStrategy failStrategy)

Method Summary

Modifier and Type	Method and Description
protected long	nowMillis() Return the current time in milliseconds.
protected void	sleep(long millis) Sleep the given number of milliseconds.
String	toString()
<F,T> T	until(F input, com.google.common.base.Function<? super F,T> stateQuery) Wait until the given input passes its state query without ignorable exception.
<F,T> T	until(F input, com.google.common.base.Function<? super F,T> stateQuery, org.hamcrest.Matcher<? super T> matcher) Wait until an expectation is met.
<F,T> T	until(String message, F input, com.google.common.base.Function<? super F,T> stateQuery, org.hamcrest.Matcher<? super T> matcher) Wait until an expectation is met.

Methods inherited from class java.lang.Object

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

Constructor Detail

DeceleratingWait

public DeceleratingWait()

DeceleratingWait

public DeceleratingWait(@Nonnull
                        Timeout timeout)

DeceleratingWait

public DeceleratingWait(@Nonnull
                        Timeout timeout,
                        @Nonnegative
                        double timeoutFactor)

DeceleratingWait

public DeceleratingWait(@Nonnull
                        Timeout timeout,
                        @Nonnull
                        WaitFailStrategy failStrategy)

DeceleratingWait

public DeceleratingWait(@Nonnull
                        Timeout timeout,
                        @Nonnegative
                        double timeoutFactor,
                        @Nonnull
                        WaitFailStrategy failStrategy)

Method Detail

nowMillis

protected long nowMillis()

Return the current time in milliseconds. Overwrite for tests.

Returns:

the current time

sleep

protected void sleep(long millis)
              throws InterruptedException

Sleep the given number of milliseconds.

Parameters:

millis - how long to sleep

Throws:

InterruptedException - if the current thread has been interrupted

until

public final <F,T> T until(@Nonnull
                           F input,
                           @Nonnull
                           com.google.common.base.Function<? super F,T> stateQuery)

Description copied from interface: Wait

Wait until the given input passes its state query without ignorable exception.

This call is equal to:

 until(null, input, stateQuery, null)
 

Specified by:

until in interface Wait

Type Parameters:

F - the input type

T - the return type of the state query

Parameters:

input - the input to pass to the query function; if implementing SelfDescribing the description of input will be queried on failure

stateQuery - the function to query the state of input; if implementing SelfDescribing the description of stateQuery will be queried on failure

Returns:

the result of the successful state query

See Also:

IgnorableStateQueryException

until

public <F,T> T until(@Nonnull
                     F input,
                     @Nonnull
                     com.google.common.base.Function<? super F,T> stateQuery,
                     @Nullable
                     org.hamcrest.Matcher<? super T> matcher)

Description copied from interface: Wait

Wait until an expectation is met. Validate the expectation with decelerating polling intervals.

Specified by:

until in interface Wait

Type Parameters:

F - the input type

T - the return type of the state query

Parameters:

input - the input to pass to the query function; if implementing SelfDescribing the description of input will be queried on failure

stateQuery - the function to query the state of input; if implementing SelfDescribing the description of stateQuery will be queried on failure

matcher - the matcher to validate the result of the query; null to match any returned value

Returns:

the result of the successful state query

until

public <F,T> T until(@Nullable
                     String message,
                     @Nonnull
                     F input,
                     @Nonnull
                     com.google.common.base.Function<? super F,T> stateQuery,
                     @Nullable
                     org.hamcrest.Matcher<? super T> matcher)

Description copied from interface: Wait

Wait until an expectation is met. Validate the expectation with decelerating polling intervals.

Specified by:

until in interface Wait

Type Parameters:

F - the input type

T - the return type of the state query

Parameters:

message - the message to print on failure; null for no additional message

input - the input to pass to the query function; if implementing SelfDescribing the description of input will be queried on failure

stateQuery - the function to query the state of input; if implementing SelfDescribing the description of stateQuery will be queried on failure

matcher - the matcher to validate the result of the query; null to match any returned value

Returns:

the result of the successful state query

toString

public String toString()

Overrides:

toString in class Object