A Resource that can be used to do IO. Primarily it wraps objects from the java io and makes them more Scala friendly.
A common question about Resource is: "Why no simply expose Input, Output, Seekable, ReadChars, WriteChars? Why do we need a Resource[R] object?"
There are several reasons for this. There are several situations where a developer needs access to the underlying resource.
Perhaps they need to interact with a Java API which does not use the Input, etc... APIs. Another possibility is that the resource may be a specific implementation like PrintStream and they want to use those custom APIs instead of the Scala IO apis. In that case Resource provides them with the ARM functionality that is very useful.
The type of the resource that will be managed by the ManagedResource
1.0
o != arg0 is the same as !(o == (arg0)).
o != arg0 is the same as !(o == (arg0)).
the object to compare against this object for dis-equality.
false if the receiver object is equivalent to the argument; true otherwise.
o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
the object to compare against this object for equality.
true if the receiver object is equivalent to the argument; false otherwise.
o == arg0 is the same as o.equals(arg0).
o == arg0 is the same as o.equals(arg0).
the object to compare against this object for equality.
true if the receiver object is equivalent to the argument; false otherwise.
Creates a CloseAction from the function and passes it to appendCloseAction(CloseAction)
Creates a CloseAction from the function and passes it to appendCloseAction(CloseAction)
The new action to append
a new instance with the added CloseAction *
Add a CloseAction to the end of the CloseAction queue (the last action executed).
Add a CloseAction to the end of the CloseAction queue (the last action executed).
The new action to append
a new instance with the added CloseAction
This method is used to cast the receiver object to be of type T0.
This method is used to 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 typed.
the receiver object.
This method creates and returns a copy of the receiver object.
This method creates and returns a copy of the receiver object.
The default implementation of the clone method is platform dependent.
a copy of the receiver object.
This method is used to test whether the argument (arg0) is a reference to the
receiver object (this).
This method is used to test whether the argument (arg0) is a reference to the
receiver object (this).
The eq method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on
non-null instances of AnyRef:
* It is reflexive: for any non-null instance x of type AnyRef, x.eq(x) returns true.
* It is symmetric: for any non-null instances x and y of type AnyRef, x.eq(y) returns true if and
only if y.eq(x) returns true.
* It is transitive: for any non-null instances x, y, and z of type AnyRef if x.eq(y) returns true
and y.eq(z) returns true, then x.eq(z) returns true.
Additionally, the eq method has three other properties.
* It is consistent: for any non-null instances 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).
the object to compare against this object for reference equality.
true if the argument is a reference to the receiver object; false otherwise.
This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.
This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.
The default implementations of this method is an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence
relation]:
* It is reflexive: for any instance x of type Any, x.equals(x) should return true.
* It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and
only if y.equals(x) returns true.
* It is transitive: for any instances x, y, and z of type AnyRef if x.equals(y) returns true and
y.equals(z) returns true, then x.equals(z) should return true.
If you override this method, you should verify that your implementation remains an equivalence relation.
Additionally, when overriding this method it is often necessary to override hashCode to ensure that objects
that are "equal" (o1.equals(o2) returns true) hash to the same scala.Int
(o1.hashCode.equals(o2.hashCode)).
the object to compare against this object for equality.
true if the receiver object is equivalent to the argument; false otherwise.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
The details of when and if the finalize method are invoked, as well as the interaction between finalize
and non-local returns and exceptions, are all platform dependent.
Returns a representation that corresponds to the dynamic class of the receiver object.
Returns a representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
Returns a hash code value for the object.
Returns a hash code value for the object.
The default hashing algorithm is platform dependent.
Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet
not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0.
However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have
identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure
to verify that the behavior is consistent with the equals method.
the hash code value for the object.
This method is used to test whether the dynamic type of the receiver object is T0.
This method is used to test whether the dynamic type of the receiver object is T0.
Note that the test 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 requested typed.
true if the receiver object is an instance of erasure of type T0; false otherwise.
o.ne(arg0) is the same as !(o.eq(arg0)).
o.ne(arg0) is the same as !(o.eq(arg0)).
the object to compare against this object for reference dis-equality.
false if the argument is not a reference to the receiver object; true otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
Creates a new instance of the underlying resource (or opens it).
Creates a new instance of the underlying resource (or opens it). Sometimes the code block used to create the Resource is non-reusable in which case this Resource can only be used once. This is not recommended. When creating a resource it is recommended to pass the code block for creating the resource to the resource so that the resource can be reused. Of course this is not always possible
This method should only be used with care in cases when Automatic
Resource Management cannot be used because the
InputStream must be closed manually.
This is public only to permit interoperability with certain Java APIs. A better pattern of use should be:
resource.acquireFor {
// call java API
}
or
val calculatedResult = resource.acquireAndGet {
// cal java API that returns a result
}
the actual resource that has been openned
Creates a CloseAction from the function and passes it to prependCloseAction(CloseAction)
Creates a CloseAction from the function and passes it to prependCloseAction(CloseAction)
The new action to prepend
a new instance with the added CloseAction *
Add a CloseAction to the front of the CloseAction queue.
Add a CloseAction to the front of the CloseAction queue.
The new action to prepend
a new instance with the added CloseAction
Returns a string representation of the object.
Returns a string representation of the object.
The default representation is platform dependent.
a string representation of the object.
A Resource that can be used to do IO. Primarily it wraps objects from the java io and makes them more Scala friendly.
A common question about Resource is: "Why no simply expose Input, Output, Seekable, ReadChars, WriteChars? Why do we need a Resource[R] object?"
There are several reasons for this. There are several situations where a developer needs access to the underlying resource.
Perhaps they need to interact with a Java API which does not use the Input, etc... APIs. Another possibility is that the resource may be a specific implementation like PrintStream and they want to use those custom APIs instead of the Scala IO apis. In that case Resource provides them with the ARM functionality that is very useful.