IndexedQueueSizeUtil (Java Concurrency Tools Core Library 4.0.1 API)

java.lang.Object
- org.jctools.queues.IndexedQueueSizeUtil

```
public final class IndexedQueueSizeUtil
extends Object
```
A note to maintainers on index assumptions: in a single threaded world it would seem intuitive to assume:
```
 producerIndex >= consumerIndex
 
```
As an invariant, but in a concurrent, long running settings all of the following need to be considered:
- consumerIndex > producerIndex : due to counter overflow (unlikey with longs, but easy to reason)
- consumerIndex > producerIndex : due to consumer FastFlow like implementation discovering the element before the counter is updated.
- producerIndex - consumerIndex < 0 : due to above.
- producerIndex - consumerIndex > Integer.MAX_VALUE : as linked buffers allow constructing queues with more than Integer.MAX_VALUE elements.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static interface IndexedQueueSizeUtil.IndexedQueue

Field Summary

Fields
Modifier and Type Field Description

static int IGNORE_PARITY_DIVISOR

static int PLAIN_DIVISOR

Constructor Summary

Constructors
Constructor Description

IndexedQueueSizeUtil()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static boolean`	`isEmpty(IndexedQueueSizeUtil.IndexedQueue iq)`
`static int`	`sanitizedSize(int capacity, long size)`
`static int`	`size(IndexedQueueSizeUtil.IndexedQueue iq, int divisor)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail
- PLAIN_DIVISOR
```
public static final int PLAIN_DIVISOR
```
  See Also:
  
  Constant Field Values
- IGNORE_PARITY_DIVISOR
```
public static final int IGNORE_PARITY_DIVISOR
```
  See Also:
  
  Constant Field Values

Constructor Detail
- IndexedQueueSizeUtil
```
public IndexedQueueSizeUtil()
```

Method Detail

size

public static int size(IndexedQueueSizeUtil.IndexedQueue iq,
                       int divisor)

sanitizedSize

public static int sanitizedSize(int capacity,
                                long size)

isEmpty

public static boolean isEmpty(IndexedQueueSizeUtil.IndexedQueue iq)