Package org.antlr.runtime.misc
Class FastQueue<T>
java.lang.Object
org.antlr.runtime.misc.FastQueue<T>
- Direct Known Subclasses:
LookaheadStream
A queue that can dequeue and get(i) in O(1) and grow arbitrarily large.
A linked list is fast at dequeue but slow at get(i). An array is
the reverse. This is O(1) for both operations.
List grows until you dequeue last element at end of buffer. Then
it resets to start filling at 0 again. If adds/removes are balanced, the
buffer will not grow too large.
No iterator stuff as that's not how we'll use it.
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Field Summary
Fields -
Constructor Summary
Constructors -
Method Summary
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Field Details
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data
dynamically-sized buffer of elements -
p
protected int pindex of next element to fill
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Constructor Details
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FastQueue
public FastQueue()
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Method Details
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reset
public void reset() -
remove
Get and remove first element in queue -
add
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size
public int size() -
head
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get
Return element i elements ahead of current element. i==0 gets current element. This is not an absolute index into the data list since p defines the start of the real list. -
clear
public void clear() -
toString
Return string of current buffer contents; non-destructive
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