Unpooled (Netty API Reference (4.1.11.Final))

java.lang.Object
- io.netty.buffer.Unpooled

```
public final class Unpooled
extends Object
```
Creates a new ByteBuf by allocating new space or by wrapping or copying existing byte arrays, byte buffers and a string.
Use static import
This classes is intended to be used with Java 5 static import statement:
```
 import static io.netty.buffer.Unpooled.*;

 ByteBuf heapBuffer    = buffer(128);
 ByteBuf directBuffer  = directBuffer(256);
 ByteBuf wrappedBuffer = wrappedBuffer(new byte[128], new byte[256]);
 ByteBuf copiedBuffer  = copiedBuffer(ByteBuffer.allocate(128));
 
```
Allocating a new buffer
Three buffer types are provided out of the box.
- buffer(int) allocates a new fixed-capacity heap buffer.
- directBuffer(int) allocates a new fixed-capacity direct buffer.
Creating a wrapped buffer
Wrapped buffer is a buffer which is a view of one or more existing byte arrays and byte buffers. Any changes in the content of the original array or buffer will be visible in the wrapped buffer. Various wrapper methods are provided and their name is all wrappedBuffer(). You might want to take a look at the methods that accept varargs closely if you want to create a buffer which is composed of more than one array to reduce the number of memory copy.
Creating a copied buffer
Copied buffer is a deep copy of one or more existing byte arrays, byte buffers or a string. Unlike a wrapped buffer, there's no shared data between the original data and the copied buffer. Various copy methods are provided and their name is all copiedBuffer(). It is also convenient to use this operation to merge multiple buffers into one buffer.

Field Summary

Fields
Modifier and Type	Field and Description
`static ByteOrder`	`BIG_ENDIAN` Big endian byte order.
`static ByteBuf`	`EMPTY_BUFFER` A buffer whose capacity is `0`.
`static ByteOrder`	`LITTLE_ENDIAN` Little endian byte order.

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static ByteBuf`	`buffer()` Creates a new big-endian Java heap buffer with reasonably small initial capacity, which expands its capacity boundlessly on demand.
`static ByteBuf`	`buffer(int initialCapacity)` Creates a new big-endian Java heap buffer with the specified `capacity`, which expands its capacity boundlessly on demand.
`static ByteBuf`	`buffer(int initialCapacity, int maxCapacity)` Creates a new big-endian Java heap buffer with the specified `initialCapacity`, that may grow up to `maxCapacity` The new buffer's `readerIndex` and `writerIndex` are `0`.
`static CompositeByteBuf`	`compositeBuffer()` Returns a new big-endian composite buffer with no components.
`static CompositeByteBuf`	`compositeBuffer(int maxNumComponents)` Returns a new big-endian composite buffer with no components.
`static ByteBuf`	`copiedBuffer(byte[]... arrays)` Creates a new big-endian buffer whose content is a merged copy of the specified `arrays`.
`static ByteBuf`	`copiedBuffer(byte[] array)` Creates a new big-endian buffer whose content is a copy of the specified `array`.
`static ByteBuf`	`copiedBuffer(byte[] array, int offset, int length)` Creates a new big-endian buffer whose content is a copy of the specified `array`'s sub-region.
`static ByteBuf`	`copiedBuffer(ByteBuf... buffers)` Creates a new buffer whose content is a merged copy of the specified `buffers`' readable bytes.
`static ByteBuf`	`copiedBuffer(ByteBuf buffer)` Creates a new buffer whose content is a copy of the specified `buffer`'s readable bytes.
`static ByteBuf`	`copiedBuffer(ByteBuffer... buffers)` Creates a new buffer whose content is a merged copy of the specified `buffers`' slices.
`static ByteBuf`	`copiedBuffer(ByteBuffer buffer)` Creates a new buffer whose content is a copy of the specified `buffer`'s current slice.
`static ByteBuf`	`copiedBuffer(char[] array, Charset charset)` Creates a new big-endian buffer whose content is the specified `array` encoded in the specified `charset`.
`static ByteBuf`	`copiedBuffer(char[] array, int offset, int length, Charset charset)` Creates a new big-endian buffer whose content is a subregion of the specified `array` encoded in the specified `charset`.
`static ByteBuf`	`copiedBuffer(CharSequence string, Charset charset)` Creates a new big-endian buffer whose content is the specified `string` encoded in the specified `charset`.
`static ByteBuf`	`copiedBuffer(CharSequence string, int offset, int length, Charset charset)` Creates a new big-endian buffer whose content is a subregion of the specified `string` encoded in the specified `charset`.
`static ByteBuf`	`copyBoolean(boolean... values)` Create a new big-endian buffer that holds a sequence of the specified boolean values.
`static ByteBuf`	`copyBoolean(boolean value)` Creates a new single-byte big-endian buffer that holds the specified boolean value.
`static ByteBuf`	`copyDouble(double... values)` Create a new big-endian buffer that holds a sequence of the specified 64-bit floating point numbers.
`static ByteBuf`	`copyDouble(double value)` Creates a new 8-byte big-endian buffer that holds the specified 64-bit floating point number.
`static ByteBuf`	`copyFloat(float... values)` Create a new big-endian buffer that holds a sequence of the specified 32-bit floating point numbers.
`static ByteBuf`	`copyFloat(float value)` Creates a new 4-byte big-endian buffer that holds the specified 32-bit floating point number.
`static ByteBuf`	`copyInt(int... values)` Create a big-endian buffer that holds a sequence of the specified 32-bit integers.
`static ByteBuf`	`copyInt(int value)` Creates a new 4-byte big-endian buffer that holds the specified 32-bit integer.
`static ByteBuf`	`copyLong(long... values)` Create a new big-endian buffer that holds a sequence of the specified 64-bit integers.
`static ByteBuf`	`copyLong(long value)` Creates a new 8-byte big-endian buffer that holds the specified 64-bit integer.
`static ByteBuf`	`copyMedium(int... values)` Create a new big-endian buffer that holds a sequence of the specified 24-bit integers.
`static ByteBuf`	`copyMedium(int value)` Creates a new 3-byte big-endian buffer that holds the specified 24-bit integer.
`static ByteBuf`	`copyShort(int... values)` Create a new big-endian buffer that holds a sequence of the specified 16-bit integers.
`static ByteBuf`	`copyShort(int value)` Creates a new 2-byte big-endian buffer that holds the specified 16-bit integer.
`static ByteBuf`	`copyShort(short... values)` Create a new big-endian buffer that holds a sequence of the specified 16-bit integers.
`static ByteBuf`	`directBuffer()` Creates a new big-endian direct buffer with reasonably small initial capacity, which expands its capacity boundlessly on demand.
`static ByteBuf`	`directBuffer(int initialCapacity)` Creates a new big-endian direct buffer with the specified `capacity`, which expands its capacity boundlessly on demand.
`static ByteBuf`	`directBuffer(int initialCapacity, int maxCapacity)` Creates a new big-endian direct buffer with the specified `initialCapacity`, that may grow up to `maxCapacity`.
`static ByteBuf`	`unmodifiableBuffer(ByteBuf... buffers)` Wrap the given `ByteBuf`s in an unmodifiable `ByteBuf`.
`static ByteBuf`	`unmodifiableBuffer(ByteBuf buffer)` Deprecated. Use `ByteBuf.asReadOnly()`.
`static ByteBuf`	`unreleasableBuffer(ByteBuf buf)` Return a unreleasable view on the given `ByteBuf` which will just ignore release and retain calls.
`static ByteBuf`	`wrappedBuffer(byte[]... arrays)` Creates a new big-endian composite buffer which wraps the specified arrays without copying them.
`static ByteBuf`	`wrappedBuffer(byte[] array)` Creates a new big-endian buffer which wraps the specified `array`.
`static ByteBuf`	`wrappedBuffer(byte[] array, int offset, int length)` Creates a new big-endian buffer which wraps the sub-region of the specified `array`.
`static ByteBuf`	`wrappedBuffer(ByteBuf... buffers)` Creates a new big-endian composite buffer which wraps the readable bytes of the specified buffers without copying them.
`static ByteBuf`	`wrappedBuffer(ByteBuf buffer)` Creates a new buffer which wraps the specified buffer's readable bytes.
`static ByteBuf`	`wrappedBuffer(ByteBuffer... buffers)` Creates a new big-endian composite buffer which wraps the slices of the specified NIO buffers without copying them.
`static ByteBuf`	`wrappedBuffer(ByteBuffer buffer)` Creates a new buffer which wraps the specified NIO buffer's current slice.
`static ByteBuf`	`wrappedBuffer(int maxNumComponents, byte[]... arrays)` Creates a new big-endian composite buffer which wraps the specified arrays without copying them.
`static ByteBuf`	`wrappedBuffer(int maxNumComponents, ByteBuf... buffers)` Creates a new big-endian composite buffer which wraps the readable bytes of the specified buffers without copying them.
`static ByteBuf`	`wrappedBuffer(int maxNumComponents, ByteBuffer... buffers)` Creates a new big-endian composite buffer which wraps the slices of the specified NIO buffers without copying them.
`static ByteBuf`	`wrappedBuffer(long memoryAddress, int size, boolean doFree)` Creates a new buffer which wraps the specified memory address.

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

- Field Detail
  - BIG_ENDIAN
```
public static final ByteOrder BIG_ENDIAN
```
    Big endian byte order.
  - LITTLE_ENDIAN
```
public static final ByteOrder LITTLE_ENDIAN
```
    Little endian byte order.
  - EMPTY_BUFFER
```
public static final ByteBuf EMPTY_BUFFER
```
    A buffer whose capacity is 0.
- Method Detail
  - buffer
```
public static ByteBuf buffer()
```
    Creates a new big-endian Java heap buffer with reasonably small initial capacity, which expands its capacity boundlessly on demand.
  - directBuffer
```
public static ByteBuf directBuffer()
```
    Creates a new big-endian direct buffer with reasonably small initial capacity, which expands its capacity boundlessly on demand.
  - buffer
```
public static ByteBuf buffer(int initialCapacity)
```
    Creates a new big-endian Java heap buffer with the specified capacity, which expands its capacity boundlessly on demand. The new buffer's readerIndex and writerIndex are 0.
  - directBuffer
```
public static ByteBuf directBuffer(int initialCapacity)
```
    Creates a new big-endian direct buffer with the specified capacity, which expands its capacity boundlessly on demand. The new buffer's readerIndex and writerIndex are 0.
  - buffer
```
public static ByteBuf buffer(int initialCapacity,
                             int maxCapacity)
```
    Creates a new big-endian Java heap buffer with the specified initialCapacity, that may grow up to maxCapacity The new buffer's readerIndex and writerIndex are 0.
  - directBuffer
```
public static ByteBuf directBuffer(int initialCapacity,
                                   int maxCapacity)
```
    Creates a new big-endian direct buffer with the specified initialCapacity, that may grow up to maxCapacity. The new buffer's readerIndex and writerIndex are 0.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(byte[] array)
```
    Creates a new big-endian buffer which wraps the specified array. A modification on the specified array's content will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(byte[] array,
                                    int offset,
                                    int length)
```
    Creates a new big-endian buffer which wraps the sub-region of the specified array. A modification on the specified array's content will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(ByteBuffer buffer)
```
    Creates a new buffer which wraps the specified NIO buffer's current slice. A modification on the specified buffer's content will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(long memoryAddress,
                                    int size,
                                    boolean doFree)
```
    Creates a new buffer which wraps the specified memory address. If doFree is true the memoryAddress will automatically be freed once the reference count of the ByteBuf reaches 0.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(ByteBuf buffer)
```
    Creates a new buffer which wraps the specified buffer's readable bytes. A modification on the specified buffer's content will be visible to the returned buffer.
    
    Parameters:
    
    buffer - The buffer to wrap. Reference count ownership of this variable is transfered to this method.
    
    Returns:
    
    The readable portion of the buffer, or an empty buffer if there is no readable portion. The caller is responsible for releasing this buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(byte[]... arrays)
```
    Creates a new big-endian composite buffer which wraps the specified arrays without copying them. A modification on the specified arrays' content will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(ByteBuf... buffers)
```
    Creates a new big-endian composite buffer which wraps the readable bytes of the specified buffers without copying them. A modification on the content of the specified buffers will be visible to the returned buffer.
    
    Parameters:
    
    buffers - The buffers to wrap. Reference count ownership of all variables is transfered to this method.
    
    Returns:
    
    The readable portion of the buffers. The caller is responsible for releasing this buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(ByteBuffer... buffers)
```
    Creates a new big-endian composite buffer which wraps the slices of the specified NIO buffers without copying them. A modification on the content of the specified buffers will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(int maxNumComponents,
                                    byte[]... arrays)
```
    Creates a new big-endian composite buffer which wraps the specified arrays without copying them. A modification on the specified arrays' content will be visible to the returned buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(int maxNumComponents,
                                    ByteBuf... buffers)
```
    Creates a new big-endian composite buffer which wraps the readable bytes of the specified buffers without copying them. A modification on the content of the specified buffers will be visible to the returned buffer.
    
    Parameters:
    
    maxNumComponents - Advisement as to how many independent buffers are allowed to exist before consolidation occurs.
    
    buffers - The buffers to wrap. Reference count ownership of all variables is transfered to this method.
    
    Returns:
    
    The readable portion of the buffers. The caller is responsible for releasing this buffer.
  - wrappedBuffer
```
public static ByteBuf wrappedBuffer(int maxNumComponents,
                                    ByteBuffer... buffers)
```
    Creates a new big-endian composite buffer which wraps the slices of the specified NIO buffers without copying them. A modification on the content of the specified buffers will be visible to the returned buffer.
  - compositeBuffer
```
public static CompositeByteBuf compositeBuffer()
```
    Returns a new big-endian composite buffer with no components.
  - compositeBuffer
```
public static CompositeByteBuf compositeBuffer(int maxNumComponents)
```
    Returns a new big-endian composite buffer with no components.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(byte[] array)
```
    Creates a new big-endian buffer whose content is a copy of the specified array. The new buffer's readerIndex and writerIndex are 0 and array.length respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(byte[] array,
                                   int offset,
                                   int length)
```
    Creates a new big-endian buffer whose content is a copy of the specified array's sub-region. The new buffer's readerIndex and writerIndex are 0 and the specified length respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(ByteBuffer buffer)
```
    Creates a new buffer whose content is a copy of the specified buffer's current slice. The new buffer's readerIndex and writerIndex are 0 and buffer.remaining respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(ByteBuf buffer)
```
    Creates a new buffer whose content is a copy of the specified buffer's readable bytes. The new buffer's readerIndex and writerIndex are 0 and buffer.readableBytes respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(byte[]... arrays)
```
    Creates a new big-endian buffer whose content is a merged copy of the specified arrays. The new buffer's readerIndex and writerIndex are 0 and the sum of all arrays' length respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(ByteBuf... buffers)
```
    Creates a new buffer whose content is a merged copy of the specified buffers' readable bytes. The new buffer's readerIndex and writerIndex are 0 and the sum of all buffers' readableBytes respectively.
    
    Throws:
    
    IllegalArgumentException - if the specified buffers' endianness are different from each other
  - copiedBuffer
```
public static ByteBuf copiedBuffer(ByteBuffer... buffers)
```
    Creates a new buffer whose content is a merged copy of the specified buffers' slices. The new buffer's readerIndex and writerIndex are 0 and the sum of all buffers' remaining respectively.
    
    Throws:
    
    IllegalArgumentException - if the specified buffers' endianness are different from each other
  - copiedBuffer
```
public static ByteBuf copiedBuffer(CharSequence string,
                                   Charset charset)
```
    Creates a new big-endian buffer whose content is the specified string encoded in the specified charset. The new buffer's readerIndex and writerIndex are 0 and the length of the encoded string respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(CharSequence string,
                                   int offset,
                                   int length,
                                   Charset charset)
```
    Creates a new big-endian buffer whose content is a subregion of the specified string encoded in the specified charset. The new buffer's readerIndex and writerIndex are 0 and the length of the encoded string respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(char[] array,
                                   Charset charset)
```
    Creates a new big-endian buffer whose content is the specified array encoded in the specified charset. The new buffer's readerIndex and writerIndex are 0 and the length of the encoded string respectively.
  - copiedBuffer
```
public static ByteBuf copiedBuffer(char[] array,
                                   int offset,
                                   int length,
                                   Charset charset)
```
    Creates a new big-endian buffer whose content is a subregion of the specified array encoded in the specified charset. The new buffer's readerIndex and writerIndex are 0 and the length of the encoded string respectively.
  - unmodifiableBuffer
```
@Deprecated
public static ByteBuf unmodifiableBuffer(ByteBuf buffer)
```
    Deprecated. Use ByteBuf.asReadOnly().
    
    Creates a read-only buffer which disallows any modification operations on the specified buffer. The new buffer has the same readerIndex and writerIndex with the specified buffer.
  - copyInt
```
public static ByteBuf copyInt(int value)
```
    Creates a new 4-byte big-endian buffer that holds the specified 32-bit integer.
  - copyInt
```
public static ByteBuf copyInt(int... values)
```
    Create a big-endian buffer that holds a sequence of the specified 32-bit integers.
  - copyShort
```
public static ByteBuf copyShort(int value)
```
    Creates a new 2-byte big-endian buffer that holds the specified 16-bit integer.
  - copyShort
```
public static ByteBuf copyShort(short... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 16-bit integers.
  - copyShort
```
public static ByteBuf copyShort(int... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 16-bit integers.
  - copyMedium
```
public static ByteBuf copyMedium(int value)
```
    Creates a new 3-byte big-endian buffer that holds the specified 24-bit integer.
  - copyMedium
```
public static ByteBuf copyMedium(int... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 24-bit integers.
  - copyLong
```
public static ByteBuf copyLong(long value)
```
    Creates a new 8-byte big-endian buffer that holds the specified 64-bit integer.
  - copyLong
```
public static ByteBuf copyLong(long... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 64-bit integers.
  - copyBoolean
```
public static ByteBuf copyBoolean(boolean value)
```
    Creates a new single-byte big-endian buffer that holds the specified boolean value.
  - copyBoolean
```
public static ByteBuf copyBoolean(boolean... values)
```
    Create a new big-endian buffer that holds a sequence of the specified boolean values.
  - copyFloat
```
public static ByteBuf copyFloat(float value)
```
    Creates a new 4-byte big-endian buffer that holds the specified 32-bit floating point number.
  - copyFloat
```
public static ByteBuf copyFloat(float... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 32-bit floating point numbers.
  - copyDouble
```
public static ByteBuf copyDouble(double value)
```
    Creates a new 8-byte big-endian buffer that holds the specified 64-bit floating point number.
  - copyDouble
```
public static ByteBuf copyDouble(double... values)
```
    Create a new big-endian buffer that holds a sequence of the specified 64-bit floating point numbers.
  - unreleasableBuffer
```
public static ByteBuf unreleasableBuffer(ByteBuf buf)
```
    Return a unreleasable view on the given ByteBuf which will just ignore release and retain calls.
  - unmodifiableBuffer
```
public static ByteBuf unmodifiableBuffer(ByteBuf... buffers)
```
    Wrap the given ByteBufs in an unmodifiable ByteBuf. Be aware the returned ByteBuf will not try to slice the given ByteBufs to reduce GC-Pressure.

Class Unpooled

Use static import

Allocating a new buffer

Creating a wrapped buffer

Creating a copied buffer

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

BIG_ENDIAN

LITTLE_ENDIAN

EMPTY_BUFFER

Method Detail

buffer

directBuffer

buffer

directBuffer

buffer

directBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

wrappedBuffer

compositeBuffer

compositeBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

copiedBuffer

unmodifiableBuffer

copyInt

copyInt

copyShort

copyShort

copyShort

copyMedium

copyMedium

copyLong

copyLong

copyBoolean

copyBoolean

copyFloat

copyFloat

copyDouble

copyDouble

unreleasableBuffer

unmodifiableBuffer