Runs a block of code on this execution context.
the task to execute
Reports that an asynchronous computation failed.
the cause of the failure
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.
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.
Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).
Returns the runtime class representation of the object.
a class object corresponding to the runtime type of the receiver.
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.
© 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
An
ExecutionContextcan execute program logic asynchronously, typically but not necessarily on a thread pool.A general purpose
ExecutionContextmust be asynchronous in executing anyRunnablethat is passed into itsexecute-method. A special purposeExecutionContextmay be synchronous but must only be passed to code that is explicitly safe to be run using a synchronously executingExecutionContext.APIs such as
Future.onCompleterequire you to provide a callback and an implicitExecutionContext. The implicitExecutionContextwill be used to execute the callback.While it is possible to simply import
scala.concurrent.ExecutionContext.Implicits.globalto obtain an implicitExecutionContext, application developers should carefully consider where they want to set execution policy; ideally, one place per application—or per logically related section of code— will make a decision about whichExecutionContextto use. That is, you will mostly want to avoid hardcoding, especially via an import,scala.concurrent.ExecutionContext.Implicits.global. The recommended approach is to add(implicit ec: ExecutionContext)to methods, or class constructor parameters, which need anExecutionContext.Then locally import a specific
ExecutionContextin one place for the entire application or module, passing it implicitly to individual methods. Alternatively define a local implicit val with the requiredExecutionContext.A custom
ExecutionContextmay be appropriate to execute code which blocks on IO or performs long-running computations.ExecutionContext.fromExecutorServiceandExecutionContext.fromExecutorare good ways to create a customExecutionContext.The intent of
ExecutionContextis to lexically scope code execution. That is, each method, class, file, package, or application determines how to run its own code. This avoids issues such as running application callbacks on a thread pool belonging to a networking library. The size of a networking library's thread pool can be safely configured, knowing that only that library's network operations will be affected. Application callback execution can be configured separately.an (implicit ec: ExecutionContext) parameter to your method.
The ExecutionContext is used to configure how and on which
thread pools Futures will run, so the specific ExecutionContext
that is selected is important.
If your application does not define an ExecutionContext elsewhere,
consider using Scala's global ExecutionContext by defining
the following:
implicit val ec: scala.concurrent.ExecutionContext = scala.concurrent.ExecutionContext.global""")