ReusableBuilder (original) (raw)
scala.collection.mutable.ReusableBuilder
ReusableBuilder is a marker trait that indicates that a Builder can be reused to build more than one instance of a collection. In particular, calling result() followed by clear() will produce a collection and reset the builder to begin building a new collection of the same type.
In general no method other than clear() may be called after result(). It is up to subclasses to implement and to document other allowed sequences of operations (e.g. calling other methods after result() in order to obtain different snapshots of a collection under construction).
Type parameters
Elem
the type of elements that get added to the builder.
To
the type of collection that it produced.
Attributes
Source
Graph
Supertypes
Known subtypes
Members list
Clears the contents of this builder.
Clears the contents of this builder. After execution of this method, the builder will contain no elements.
If executed immediately after a call to result(), this allows a new instance of the same type of collection to be built.
Attributes
Definition Classes
Source
Produces a collection from the added elements.
Produces a collection from the added elements.
After a call to result, the behavior of all other methods is undefined save for clear(). If clear() is called, then the builder is reset and may be used to build another instance.
Attributes
Returns
a collection containing the elements added to this builder.
Definition Classes
Source
Adds all elements produced by an IterableOnce to this growable collection.
Adds all elements produced by an IterableOnce to this growable collection.
Value parameters
elems
the IterableOnce producing the elements to add.
Attributes
Returns
the growable collection itself.
Inherited from:
Source
The number of elements in the collection under construction, if it can be cheaply computed, -1 otherwise.
The number of elements in the collection under construction, if it can be cheaply computed, -1 otherwise.
Attributes
Returns
The number of elements. The default implementation always returns -1.
Inherited from:
Source
A builder resulting from this builder by mapping the result using f.
A builder resulting from this builder by mapping the result using f.
Attributes
Inherited from:
Source
Gives a hint that the result of this builder is expected to have the same size as the given collection, plus some delta.
Gives a hint that the result of this builder is expected to have the same size as the given collection, plus some delta.
This method provides a hint only if the collection has a known size, as specified by the following pseudocode:
if (coll.knownSize != -1)
if (coll.knownSize + delta <= 0) sizeHint(0)
else sizeHint(coll.knownSize + delta)
If the delta is negative and the result size is known to be negative, then the size hint is issued at zero.
Some builder classes will optimize their representation based on the hint. However, builder implementations are required to work correctly even if the hint is wrong, i.e., if a different number of elements is added.
Value parameters
coll
the collection which serves as a hint for the result's size.
delta
a correction to add to the coll.size to produce the size hint (zero if omitted).
Attributes
Inherited from:
Source
Gives a hint how many elements are expected to be added in total by the time result is called.
Gives a hint how many elements are expected to be added in total by the time result is called.
Some builder classes will optimize their representation based on the hint. However, builder implementations are required to work correctly even if the hint is wrong, e.g., a different number of elements is added, or the hint is out of range.
The default implementation simply ignores the hint.
Value parameters
size
the hint how many elements will be added.
Attributes
Inherited from:
Source
Gives a hint how many elements are expected to be added when the next result is called, together with an upper bound given by the size of some other collection.
Gives a hint how many elements are expected to be added when the next result is called, together with an upper bound given by the size of some other collection. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.
Value parameters
boundingColl
the bounding collection. If it is an IndexedSeqLike, then sizes larger than collection's size are reduced.
size
the hint how many elements will be added.
Attributes
Inherited from:
Source
Adds a single element to this growable collection.
Adds a single element to this growable collection.
Value parameters
elem
the element to add.
Attributes
Returns
the growable collection itself
Inherited from:
Source
Adds two or more elements to this growable collection.
Adds two or more elements to this growable collection.
Value parameters
elem1
the first element to add.
elem2
the second element to add.
elems
the remaining elements to add.
Attributes
Returns
the growable collection itself
Deprecated
[Since version 2.13.0] Use `++=` aka `addAll` instead of varargs `+=`; infix operations with an operand of multiple args will be deprecated
Inherited from:
Source
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