Using (original) (raw)
A resource manager.
A resource manager.
Resources can be registered with the manager by calling acquire; such resources will be released in reverse order of their acquisition when the manager is closed, regardless of any exceptions thrown during use.
See the main doc for Using for full details of suppression behavior.
Attributes
Note
It is recommended for API designers to require an implicit Manager for the creation of custom resources, and to call acquire during those resources' construction. Doing so guarantees that the resource must be automatically managed, and makes it impossible to forget to do so. Example:
class SafeFileReader(file: File)(implicit manager: Using.Manager)
extends BufferedReader(new FileReader(file)) {
def this(fileName: String)(implicit manager: Using.Manager) = this(new File(fileName))
manager.acquire(this)
}
Companion
Source
Supertypes
A type class describing how to release a particular type of resource.
A type class describing how to release a particular type of resource.
A resource is anything which needs to be released, closed, or otherwise cleaned up in some way after it is finished being used, and for which waiting for the object's garbage collection to be cleaned up would be unacceptable. For example, an instance of java.io.OutputStream would be considered a resource, because it is important to close the stream after it is finished being used.
An instance of Releasable is needed in order to automatically manage a resource with Using. An implicit instance is provided for all types extending java.lang.AutoCloseable.
Type parameters
R
the type of the resource
Attributes
Companion
Source
Supertypes
Known subtypes
Performs an operation using a resource, and then releases the resource, even if the operation throws an exception.
Performs an operation using a resource, and then releases the resource, even if the operation throws an exception.
See the main doc for Using for full details of suppression behavior.
Attributes
Returns
a Try containing an exception if one or more were thrown, or the result of the operation if no exceptions were thrown
Source
Performs an operation using a resource, and then releases the resource, even if the operation throws an exception.
Performs an operation using a resource, and then releases the resource, even if the operation throws an exception. This method behaves similarly to Java's try-with-resources.
See the main doc for Using for full details of suppression behavior.
Type parameters
A
the return type of the operation
R
the type of the resource
Value parameters
body
the operation to perform with the resource
resource
the resource
Attributes
Returns
the result of the operation, if neither the operation nor releasing the resource throws
Source
Performs an operation using two resources, and then releases the resources in reverse order, even if the operation throws an exception.
Performs an operation using two resources, and then releases the resources in reverse order, even if the operation throws an exception. This method behaves similarly to Java's try-with-resources.
See the main doc for Using for full details of suppression behavior.
Type parameters
A
the return type of the operation
R1
the type of the first resource
R2
the type of the second resource
Value parameters
body
the operation to perform using the resources
resource1
the first resource
resource2
the second resource
Attributes
Returns
the result of the operation, if neither the operation nor releasing the resources throws
Source
Performs an operation using three resources, and then releases the resources in reverse order, even if the operation throws an exception.
Performs an operation using three resources, and then releases the resources in reverse order, even if the operation throws an exception. This method behaves similarly to Java's try-with-resources.
See the main doc for Using for full details of suppression behavior.
Type parameters
A
the return type of the operation
R1
the type of the first resource
R2
the type of the second resource
R3
the type of the third resource
Value parameters
body
the operation to perform using the resources
resource1
the first resource
resource2
the second resource
resource3
the third resource
Attributes
Returns
the result of the operation, if neither the operation nor releasing the resources throws
Source
Performs an operation using four resources, and then releases the resources in reverse order, even if the operation throws an exception.
Performs an operation using four resources, and then releases the resources in reverse order, even if the operation throws an exception. This method behaves similarly to Java's try-with-resources.
See the main doc for Using for full details of suppression behavior.
Type parameters
A
the return type of the operation
R1
the type of the first resource
R2
the type of the second resource
R3
the type of the third resource
R4
the type of the fourth resource
Value parameters
body
the operation to perform using the resources
resource1
the first resource
resource2
the second resource
resource3
the third resource
resource4
the fourth resource
Attributes
Returns
the result of the operation, if neither the operation nor releasing the resources throws
Source