java.lang.Object
- io.netty.util.Recycler<T>

Type Parameters:

T - the type of the pooled object

Direct Known Subclasses:

AdaptivePoolingAllocator.Magazine.AdaptiveRecycler
```
public abstract class Recycler<T>
extends java.lang.Object
```
Light-weight object pool based on a thread-local stack.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`private static class`	`Recycler.BlockingMessageQueue<T>`	This is an implementation of `MessagePassingQueue`, similar to what might be returned from `PlatformDependent.newMpscQueue(int)`, but intended to be used for debugging purpose.
`private static class`	`Recycler.DefaultHandle<T>`
`static class`	`Recycler.EnhancedHandle<T>`
`private static class`	`Recycler.GuardedLocalPool<T>`
`static interface`	`Recycler.Handle<T>`
`private static class`	`Recycler.LocalPool<H,T>`
`private static class`	`Recycler.LocalPoolHandle<T>`	We created this handle to avoid having more than 2 concrete implementations of `Recycler.EnhancedHandle` i.e.
`private static class`	`Recycler.UnguardedLocalPool<T>`

Field Summary

Fields
Modifier and Type	Field	Description
`private static boolean`	`BATCH_FAST_TL_ONLY`
`private static boolean`	`BLOCKING_POOL`
`private static int`	`DEFAULT_INITIAL_MAX_CAPACITY_PER_THREAD`
`private static int`	`DEFAULT_MAX_CAPACITY_PER_THREAD`
`private static int`	`DEFAULT_QUEUE_CHUNK_SIZE_PER_THREAD`
`private Recycler.LocalPool<?,T>`	`localPool`
`private static InternalLogger`	`logger`
`private static Recycler.EnhancedHandle<?>`	`NOOP_HANDLE`
`private static Recycler.UnguardedLocalPool<?>`	`NOOP_LOCAL_POOL`
`private static int`	`RATIO`
`private FastThreadLocal<Recycler.LocalPool<?,T>>`	`threadLocalPool`

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`Recycler()`
`protected`	`Recycler(boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded = true`: it means that `ObjectPool.Handle.recycle(Object)` is not checking that `object` is the same which was recycled and assume no other recycling happens concurrently (similar to what `Recycler.EnhancedHandle.unguardedRecycle(Object)` does).
`protected`	`Recycler(int maxCapacityPerThread)`
`protected`	`Recycler(int maxCapacity, boolean unguarded)`	USE IT CAREFULLY! This is creating a shareable `Recycler` which `get()` can be called concurrently from different `Thread`s. Usually `Recycler`s uses some form of thread-local storage, but this constructor is disabling it and using a single pool of instances instead, sized as `maxCapacity` This is NOT enforcing pooled instances states to be validated if `unguarded = true`: it means that `ObjectPool.Handle.recycle(Object)` is not checking that `object` is the same which was recycled and assume no other recycling happens concurrently (similar to what `Recycler.EnhancedHandle.unguardedRecycle(Object)` does).
`protected`	`Recycler(int maxCapacityPerThread, int maxSharedCapacityFactor)`	Deprecated. Use one of the following instead: `Recycler()`, `Recycler(int)`, `Recycler(int, int, int)`.
`protected`	`Recycler(int chunksSize, int maxCapacityPerThread, boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded = true` as stated by `Recycler(boolean)`, but it allows to tune the chunk size used for local pooling.
`protected`	`Recycler(int maxCapacityPerThread, int interval, int chunkSize)`
`protected`	`Recycler(int maxCapacityPerThread, int interval, int chunkSize, boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded =true` as stated by `Recycler(boolean)`.
`private`	`Recycler(int maxCapacityPerThread, int ratio, int chunkSize, boolean useThreadLocalStorage, java.lang.Thread owner, boolean unguarded)`
`protected`	`Recycler(int maxCapacityPerThread, int maxSharedCapacityFactor, int ratio, int maxDelayedQueuesPerThread)`	Deprecated. Use one of the following instead: `Recycler()`, `Recycler(int)`, `Recycler(int, int, int)`.
`protected`	`Recycler(int maxCapacityPerThread, int maxSharedCapacityFactor, int ratio, int maxDelayedQueuesPerThread, int delayedQueueRatio)`	Deprecated. Use one of the following instead: `Recycler()`, `Recycler(int)`, `Recycler(int, int, int)`.
`protected`	`Recycler(int maxCapacityPerThread, int interval, int chunkSize, java.lang.Thread owner, boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded =true` as stated by `Recycler(boolean)`.
`protected`	`Recycler(int chunkSize, int maxCapacityPerThread, java.lang.Thread owner, boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded = true` and allows pinning the recycler to a specific `Thread`, as stated by `Recycler(Thread, boolean)`. It also allows tuning the chunk size used for local pooling and the max capacity per thread.
`protected`	`Recycler(java.lang.Thread owner, boolean unguarded)`	USE IT CAREFULLY! This is NOT enforcing pooled instances states to be validated if `unguarded = true` as stated by `Recycler(boolean)` and allows to pin the recycler to a specific `Thread`, if `owner` is not `null`.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`T`	`get()`
`protected abstract T`	`newObject(Recycler.Handle<T> handle)`
`boolean`	`recycle(T o, Recycler.Handle<T> handle)`	Deprecated. use `ObjectPool.Handle.recycle(Object)`.
`(package private) int`	`threadLocalSize()`
`static void`	`unpinOwner(Recycler<?> recycler)`	Disassociates the `Recycler` from the current `Thread` if it was pinned, see `Recycler(Thread, boolean)`.

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

- Field Detail
  - logger
```
private static final InternalLogger logger
```
  - NOOP_HANDLE
```
private static final Recycler.EnhancedHandle<?> NOOP_HANDLE
```
  - NOOP_LOCAL_POOL
```
private static final Recycler.UnguardedLocalPool<?> NOOP_LOCAL_POOL
```
  - DEFAULT_INITIAL_MAX_CAPACITY_PER_THREAD
```
private static final int DEFAULT_INITIAL_MAX_CAPACITY_PER_THREAD
```
    See Also:
    
    Constant Field Values
  - DEFAULT_MAX_CAPACITY_PER_THREAD
```
private static final int DEFAULT_MAX_CAPACITY_PER_THREAD
```
  - RATIO
```
private static final int RATIO
```
  - DEFAULT_QUEUE_CHUNK_SIZE_PER_THREAD
```
private static final int DEFAULT_QUEUE_CHUNK_SIZE_PER_THREAD
```
  - BLOCKING_POOL
```
private static final boolean BLOCKING_POOL
```
  - BATCH_FAST_TL_ONLY
```
private static final boolean BATCH_FAST_TL_ONLY
```
  - localPool
```
private final Recycler.LocalPool<?,T> localPool
```
  - threadLocalPool
```
private final FastThreadLocal<Recycler.LocalPool<?,T>> threadLocalPool
```
- Constructor Detail
  - Recycler
```
protected Recycler(int maxCapacity,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is creating a shareable Recycler which get() can be called concurrently from different Threads.
    Usually Recyclers uses some form of thread-local storage, but this constructor is disabling it and using a single pool of instances instead, sized as maxCapacity
    This is NOT enforcing pooled instances states to be validated if unguarded = true: it means that ObjectPool.Handle.recycle(Object) is not checking that object is the same which was recycled and assume no other recycling happens concurrently (similar to what Recycler.EnhancedHandle.unguardedRecycle(Object) does).
  - Recycler
```
protected Recycler(boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded = true: it means that ObjectPool.Handle.recycle(Object) is not checking that object is the same which was recycled and assume no other recycling happens concurrently (similar to what Recycler.EnhancedHandle.unguardedRecycle(Object) does).
  - Recycler
```
protected Recycler(java.lang.Thread owner,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded = true as stated by Recycler(boolean) and allows to pin the recycler to a specific Thread, if owner is not null.
    Since this method has been introduced for performance-sensitive cases it doesn't validate if get() is called from the owner Thread: it assumes get() to never happen concurrently.
  - Recycler
```
protected Recycler(int maxCapacityPerThread)
```
  - Recycler
```
protected Recycler()
```
  - Recycler
```
protected Recycler(int chunksSize,
                   int maxCapacityPerThread,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded = true as stated by Recycler(boolean), but it allows to tune the chunk size used for local pooling.
  - Recycler
```
protected Recycler(int chunkSize,
                   int maxCapacityPerThread,
                   java.lang.Thread owner,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded = true and allows pinning the recycler to a specific Thread, as stated by Recycler(Thread, boolean).
    It also allows tuning the chunk size used for local pooling and the max capacity per thread.
    
    Throws:
    
    java.lang.IllegalArgumentException - if owner is null.
  - Recycler
```
@Deprecated
protected Recycler(int maxCapacityPerThread,
                   int maxSharedCapacityFactor)
```
    Deprecated.
    Use one of the following instead: Recycler(), Recycler(int), Recycler(int, int, int).
  - Recycler
```
@Deprecated
protected Recycler(int maxCapacityPerThread,
                   int maxSharedCapacityFactor,
                   int ratio,
                   int maxDelayedQueuesPerThread)
```
    Deprecated.
    Use one of the following instead: Recycler(), Recycler(int), Recycler(int, int, int).
  - Recycler
```
@Deprecated
protected Recycler(int maxCapacityPerThread,
                   int maxSharedCapacityFactor,
                   int ratio,
                   int maxDelayedQueuesPerThread,
                   int delayedQueueRatio)
```
    Deprecated.
    Use one of the following instead: Recycler(), Recycler(int), Recycler(int, int, int).
  - Recycler
```
protected Recycler(int maxCapacityPerThread,
                   int interval,
                   int chunkSize)
```
  - Recycler
```
protected Recycler(int maxCapacityPerThread,
                   int interval,
                   int chunkSize,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded =true as stated by Recycler(boolean).
  - Recycler
```
protected Recycler(int maxCapacityPerThread,
                   int interval,
                   int chunkSize,
                   java.lang.Thread owner,
                   boolean unguarded)
```
    USE IT CAREFULLY!
    This is NOT enforcing pooled instances states to be validated if unguarded =true as stated by Recycler(boolean).
  - Recycler
```
private Recycler(int maxCapacityPerThread,
                 int ratio,
                 int chunkSize,
                 boolean useThreadLocalStorage,
                 java.lang.Thread owner,
                 boolean unguarded)
```
- Method Detail
  - get
```
public final T get()
```
  - unpinOwner
```
public static void unpinOwner(Recycler<?> recycler)
```
    Disassociates the Recycler from the current Thread if it was pinned, see Recycler(Thread, boolean).
    Be aware that this method is not thread-safe: it's necessary to allow a Thread to be garbage collected even if Recycler.Handles are still referenced by other objects.
  - recycle
```
@Deprecated
public final boolean recycle(T o,
                             Recycler.Handle<T> handle)
```
    Deprecated.
    use ObjectPool.Handle.recycle(Object).
  - threadLocalSize
```
final int threadLocalSize()
```
  - newObject
```
protected abstract T newObject(Recycler.Handle<T> handle)
```
    Parameters:
    
    handle - can NOT be null.

Class Recycler<T>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

logger

NOOP_HANDLE

NOOP_LOCAL_POOL

DEFAULT_INITIAL_MAX_CAPACITY_PER_THREAD

DEFAULT_MAX_CAPACITY_PER_THREAD

RATIO

DEFAULT_QUEUE_CHUNK_SIZE_PER_THREAD

BLOCKING_POOL

BATCH_FAST_TL_ONLY

localPool

threadLocalPool

Constructor Detail

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Recycler

Method Detail

get

unpinOwner

recycle

threadLocalSize

newObject