org.keycloak.common.util.Retry クラス

org.keycloak.common.util.Retry 連携図

クラス
interface	AdvancedRunnable
interface	Supplier

静的公開メンバ関数
static int	execute (Runnable runnable, int attemptsCount, long intervalMillis)
static int	executeWithBackoff (AdvancedRunnable runnable, int attemptsCount, int intervalBaseMillis)
static< T > T	call (Supplier< T > supplier, int attemptsCount, long intervalMillis)

静的非公開メンバ関数
static int	computeBackoffInterval (int base, int iteration)

詳解

著者

Stian Thorgersen

関数詳解

call()

static <T> T org.keycloak.common.util.Retry.call ( Supplier< T >  supplier, int  attemptsCount, long  intervalMillis  )

inlinestatic

Runs the given

runnable 

at most

attemptsCount 

times until it passes, leaving

intervalMillis 

milliseconds between the invocations. The runnable is reexecuted if it throws a RuntimeException or AssertionError.

引数

supplier
attemptsCount	Total number of attempts to execute the runnable
intervalMillis

戻り値

Value generated by the

supplier 

.

                                                                                           {
        int iteration = 0;
        while (true) {
            try {
                return supplier.get(iteration);
            } catch (RuntimeException | AssertionError e) {
                attemptsCount--;
                iteration++;
                if (attemptsCount > 0) {
                    try {
                        if (intervalMillis > 0) {
                            Thread.sleep(intervalMillis);
                        }
                    } catch (InterruptedException ie) {
                        ie.addSuppressed(e);
                        throw new RuntimeException(ie);
                    }
                } else {
                    throw e;
                }
            }
        }
    }

computeBackoffInterval()

static int org.keycloak.common.util.Retry.computeBackoffInterval ( int  base, int  iteration  )

inlinestaticprivate

                                                                       {
        int iterationBase = base * (int)Math.pow(2, iteration);
        return new Random().nextInt(iterationBase);
    }

execute()

static int org.keycloak.common.util.Retry.execute ( Runnable  runnable, int  attemptsCount, long  intervalMillis  )

inlinestatic

Runs the given

runnable 

at most

attemptsCount 

times until it passes, leaving

intervalMillis 

milliseconds between the invocations. The runnable is reexecuted if it throws a RuntimeException or AssertionError.

引数

runnable
attemptsCount	Total number of attempts to execute the runnable
intervalMillis

戻り値

Index of the first successful invocation, starting from 0.

                                                                                         {
        int iteration = 0;
        while (true) {
            try {
                runnable.run();
                return iteration;
            } catch (RuntimeException | AssertionError e) {
                attemptsCount--;
                iteration++;
                if (attemptsCount > 0) {
                    try {
                        if (intervalMillis > 0) {
                            Thread.sleep(intervalMillis);
                        }
                    } catch (InterruptedException ie) {
                        ie.addSuppressed(e);
                        throw new RuntimeException(ie);
                    }
                } else {
                    throw e;
                }
            }
        }
    }

executeWithBackoff()

static int org.keycloak.common.util.Retry.executeWithBackoff ( AdvancedRunnable  runnable, int  attemptsCount, int  intervalBaseMillis  )

inlinestatic

Runs the given

runnable 

at most

attemptsCount 

times until it passes, leaving some increasing random delay milliseconds between the invocations. It uses Exponential backoff + jitter algorithm to compute the delay. More details https://aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter/

The base for delay is specified by

intervalBaseMillis 

number.

The runnable is reexecuted if it throws a RuntimeException or AssertionError.

引数

runnable
attemptsCount	Total number of attempts to execute the runnable
intervalBaseMillis	base for the exponential backoff + jitter

戻り値

Index of the first successful invocation, starting from 0.

                                                                                                               {
        int iteration = 0;
        while (true) {
            try {
                runnable.run(iteration);
                return iteration;
            } catch (RuntimeException | AssertionError e) {
                attemptsCount--;
                iteration++;
                if (attemptsCount > 0) {
                    try {
                        if (intervalBaseMillis > 0) {
                            int delay = computeBackoffInterval(intervalBaseMillis, iteration);
                            Thread.sleep(delay);
                        }
                    } catch (InterruptedException ie) {
                        ie.addSuppressed(e);
                        throw new RuntimeException(ie);
                    }
                } else {
                    throw e;
                }
            }
        }
    }

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このクラス詳解は次のファイルから抽出されました:

• D:/AppData/doxygen/keycloak/src/keycloak/src/main/java/org/keycloak/common/util/Retry.java