Package com.couchbase.client.core.utils

Class Blocking

java.lang.Object

com.couchbase.client.core.utils.Blocking

@Uncommitted
@Private
public class Blocking
extends Object

Contains various utility methods related to blocking operations. Note that this class has been moved over from "java-client" into "core-io" in the 1.3.0 timeframe. On earlier versions, it's counterpart can be found in the "java-client" library which depends on "core-io".

Since:

1.3.0

Author:

Michael Nitschinger

Constructor Summary

Constructors

Constructor	Description
Blocking()

Method Summary

Modifier and Type	Method	Description
static <T> T	blockForSingle(rx.Observable<? extends T> observable, long timeout, TimeUnit tu)	Blocks on an Observable and returns a single event or throws an Exception.

Methods inherited from class java.lang.Object

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

Constructor Details

Blocking

public Blocking()

Method Details

blockForSingle

public static <T> T blockForSingle(rx.Observable<? extends T> observable,
long timeout,
TimeUnit tu)

Blocks on an Observable and returns a single event or throws an Exception. Note that when this method is used, only the first item emitted will be returned. The caller needs to make sure that the source Observable only ever returns a single item (or none). The BlockingObservable code applies different operators like single, last, first and more, these need to be applied manually. This code is based on BlockingObservable.blockForSingle(rx.Observable<? extends T>), but does not wait forever. Instead, it utilizes the internal CountDownLatch to optimize the timeout case, with less GC and CPU overhead than chaining in an Observable.timeout(long, TimeUnit) operator. If an error happens inside the Observable, it will be raised as an Exception. If the timeout kicks in, a TimeoutException nested in a RuntimeException is thrown to be fully compatible with the Observable.timeout(long, TimeUnit) behavior.

Type Parameters:

T - the type returned.

Parameters:

observable - the source Observable

timeout - the maximum timeout before an exception is thrown.

tu - the timeout unit.

Returns:

the extracted value from the Observable or throws in an error case.