public class BoundedLinkedQueue extends java.lang.Object implements BoundedChannel
Modifier and Type | Field and Description |
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protected int |
capacity_
Number of elements allowed
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protected LinkedNode |
head_
Dummy header node of list.
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protected LinkedNode |
last_
The last node of list.
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protected java.lang.Object |
putGuard_
Helper monitor.
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protected int |
putSidePutPermits_
One side of a split permit count.
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protected java.lang.Object |
takeGuard_
Helper monitor.
|
protected int |
takeSidePutPermits_
Number of takes since last reconcile
|
Constructor and Description |
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BoundedLinkedQueue()
Create a queue with the current default capacity
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BoundedLinkedQueue(int capacity)
Create a queue with the given capacity
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Modifier and Type | Method and Description |
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protected void |
allowTake()
Notify a waiting take if needed
|
int |
capacity()
Return the current capacity of this queue
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protected java.lang.Object |
extract()
Main mechanics for take/poll
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protected void |
insert(java.lang.Object x)
Create and insert a node.
|
boolean |
isEmpty() |
boolean |
offer(java.lang.Object x,
long msecs)
Place item in channel only if it can be accepted within
msecs milliseconds.
|
java.lang.Object |
peek()
Return, but do not remove object at head of Channel,
or null if it is empty.
|
java.lang.Object |
poll(long msecs)
Return and remove an item from channel only if one is available within
msecs milliseconds.
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void |
put(java.lang.Object x)
Place item in the channel, possibly waiting indefinitely until
it can be accepted.
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protected int |
reconcilePutPermits()
Move put permits from take side to put side;
return the number of put side permits that are available.
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void |
setCapacity(int newCapacity)
Reset the capacity of this queue.
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int |
size()
Return the number of elements in the queue.
|
java.lang.Object |
take()
Return and remove an item from channel,
possibly waiting indefinitely until
such an item exists.
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protected LinkedNode head_
protected LinkedNode last_
protected final java.lang.Object putGuard_
protected final java.lang.Object takeGuard_
protected int capacity_
protected int putSidePutPermits_
protected int takeSidePutPermits_
public BoundedLinkedQueue(int capacity)
java.lang.IllegalArgumentException
- if capacity less or equal to zeropublic BoundedLinkedQueue()
protected final int reconcilePutPermits()
public int capacity()
capacity
in interface BoundedChannel
public int size()
public void setCapacity(int newCapacity)
java.lang.IllegalArgumentException
- if capacity less or equal to zeroprotected java.lang.Object extract()
public java.lang.Object peek()
Channel
public java.lang.Object take() throws java.lang.InterruptedException
Channel
take
in interface Channel
take
in interface Takable
java.lang.InterruptedException
- if the current thread has
been interrupted at a point at which interruption
is detected, in which case state of the channel is unchanged.public java.lang.Object poll(long msecs) throws java.lang.InterruptedException
Channel
poll
in interface Channel
poll
in interface Takable
msecs
- the number of milliseconds to wait. If less than
or equal to zero, the operation does not perform any timed waits,
but might still require
access to a synchronization lock, which can impose unbounded
delay if there is a lot of contention for the channel.java.lang.InterruptedException
- if the current thread has
been interrupted at a point at which interruption
is detected, in which case state of the channel is unchanged
(i.e., equivalent to a null return).protected final void allowTake()
protected void insert(java.lang.Object x)
public void put(java.lang.Object x) throws java.lang.InterruptedException
Channel
put
in interface Channel
put
in interface Puttable
x
- the element to be inserted. Should be non-null.java.lang.InterruptedException
- if the current thread has
been interrupted at a point at which interruption
is detected, in which case the element is guaranteed not
to be inserted. Otherwise, on normal return, the element is guaranteed
to have been inserted.public boolean offer(java.lang.Object x, long msecs) throws java.lang.InterruptedException
Channel
offer
in interface Channel
offer
in interface Puttable
x
- the element to be inserted. Should be non-null.msecs
- the number of milliseconds to wait. If less than
or equal to zero, the method does not perform any timed waits,
but might still require
access to a synchronization lock, which can impose unbounded
delay if there is a lot of contention for the channel.java.lang.InterruptedException
- if the current thread has
been interrupted at a point at which interruption
is detected, in which case the element is guaranteed not
to be inserted (i.e., is equivalent to a false return).public boolean isEmpty()