Test two objects for inequality.
true
if !(this == that), false otherwise.
Equivalent to x.hashCode
except for boxed numeric types and null
. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null
returns a hashcode where null.hashCode
throws a NullPointerException
.
a hash value consistent with ==
The expression x == that
is equivalent to if (x eq null) that eq null else x.equals(that)
.
true
if the receiver object is equivalent to the argument; false
otherwise.
Cast the receiver object to be of type T0
.
Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String]
will throw a ClassCastException
at runtime, while the expression List(1).asInstanceOf[List[String]]
will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.
the receiver object.
ClassCastException
if the receiver object is not an instance of the erasure of type T0
.
Create a copy of the receiver object.
The default implementation of the clone
method is platform dependent.
a copy of the receiver object.
The default reporter simply prints the stack trace of the Throwable
to System.err.
the function for error reporting
Tests whether the argument (that
) is a reference to the receiver object (this
).
The eq
method implements an equivalence relation on non-null instances of AnyRef
, and has three additional properties:
x
and y
of type AnyRef
, multiple invocations of x.eq(y)
consistently returns true
or consistently returns false
.For any non-null instance x
of type AnyRef
, x.eq(null)
and null.eq(x)
returns false
.
null.eq(null)
returns true
. When overriding the equals
or hashCode
methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2
), they should be equal to each other (o1 == o2
) and they should hash to the same value (o1.hashCode == o2.hashCode
).
true
if the argument is a reference to the receiver object; false
otherwise.
The equality method for reference types. Default implementation delegates to eq
.
See also equals
in scala.Any.
true
if the receiver object is equivalent to the argument; false
otherwise.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the finalize
method is invoked, as well as the interaction between finalize
and non-local returns and exceptions, are all platform dependent.
Creates an ExecutionContext
from the given Executor
with the default reporter.
the Executor
to use. If null
, a new Executor
is created with default configuration.
the ExecutionContext
using the given Executor
Creates an ExecutionContext
from the given Executor
.
the Executor
to use. If null
, a new Executor
is created with default configuration.
a function for error reporting
the ExecutionContext
using the given Executor
Creates an ExecutionContext
from the given ExecutorService
with the default reporter.
If it is guaranteed that none of the executed tasks are blocking, a single-threaded ExecutorService
can be used to create an ExecutionContext
as follows:
import java.util.concurrent.Executors val ec = ExecutionContext.fromExecutorService(Executors.newSingleThreadExecutor())
the ExecutorService
to use. If null
, a new ExecutorService
is created with default configuration.
the ExecutionContext
using the given ExecutorService
Creates an ExecutionContext
from the given ExecutorService
.
the ExecutorService
to use. If null
, a new ExecutorService
is created with default configuration.
a function for error reporting
the ExecutionContext
using the given ExecutorService
Returns the runtime class representation of the object.
a class object corresponding to the runtime type of the receiver.
The explicit global ExecutionContext
. Invoke global
when you want to provide the global ExecutionContext
explicitly.
The default ExecutionContext
implementation is backed by a work-stealing thread pool. It can be configured via the following scala.sys.SystemProperties:
scala.concurrent.context.minThreads
= defaults to "1" scala.concurrent.context.numThreads
= defaults to "x1" (i.e. the current number of available processors * 1) scala.concurrent.context.maxThreads
= defaults to "x1" (i.e. the current number of available processors * 1) scala.concurrent.context.maxExtraThreads
= defaults to "256"
The pool size of threads is then numThreads
bounded by minThreads
on the lower end and maxThreads
on the high end.
The maxExtraThreads
is the maximum number of extra threads to have at any given time to evade deadlock, see scala.concurrent.BlockContext.
the global ExecutionContext
The hashCode method for reference types. See hashCode in scala.Any.
the hash code value for this object.
Test whether the dynamic type of the receiver object is T0
.
Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String]
will return false
, while the expression List(1).isInstanceOf[List[String]]
will return true
. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.
true
if the receiver object is an instance of erasure of type T0
; false
otherwise.
Equivalent to !(this eq that)
.
true
if the argument is not a reference to the receiver object; false
otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
a String representation of the object.
WARNING: Only ever execute logic which will quickly return control to the caller.
This ExecutionContext
steals execution time from other threads by having its Runnable
s run on the Thread
which calls execute
and then yielding back control to the caller after *all* its Runnable
s have been executed. Nested invocations of execute
will be trampolined to prevent uncontrolled stack space growth.
When using parasitic
with abstractions such as Future
it will in many cases be non-deterministic as to which Thread
will be executing the logic, as it depends on when/if that Future
is completed.
Do *not* call any blocking code in the Runnable
s submitted to this ExecutionContext
as it will prevent progress by other enqueued Runnable
s and the calling Thread
.
Symptoms of misuse of this ExecutionContext
include, but are not limited to, deadlocks and severe performance problems.
Any NonFatal
or InterruptedException
s will be reported to the defaultReporter
.
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala/concurrent/ExecutionContext$.html
Contains factory methods for creating execution contexts.