java.lang.Object
- org.apache.lucene.store.DataOutput
- - org.apache.lucene.store.ByteBuffersDataOutput

All Implemented Interfaces:: Accountable

public final class ByteBuffersDataOutput
extends DataOutput
implements Accountable

A DataOutput storing data in a list of ByteBuffers.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class ByteBuffersDataOutput.ByteBufferRecycler
An implementation of a ByteBuffer allocation and recycling policy.

Field Summary

Fields
Modifier and Type	Field	Description
`static IntFunction<ByteBuffer>`	`ALLOCATE_BB_ON_HEAP`
`static int`	`DEFAULT_MAX_BITS_PER_BLOCK`	Default `maxBitsPerBlock`
`static int`	`DEFAULT_MIN_BITS_PER_BLOCK`	Default `minBitsPerBlock`
`static int`	`LIMIT_MAX_BITS_PER_BLOCK`	Largest `maxBitsPerBlock` allowed
`static int`	`LIMIT_MIN_BITS_PER_BLOCK`	Smallest `minBitsPerBlock` allowed
`static Consumer<ByteBuffer>`	`NO_REUSE`	A singleton instance of "no-reuse" buffer strategy.

Fields inherited from interface org.apache.lucene.util.Accountable
NULL_ACCOUNTABLE

Constructor Summary

Constructors
Constructor	Description
`ByteBuffersDataOutput()`	Creates a new output with all defaults.
`ByteBuffersDataOutput(int minBitsPerBlock, int maxBitsPerBlock, IntFunction<ByteBuffer> blockAllocate, Consumer<ByteBuffer> blockReuse)`	Expert: Creates a new output with custom parameters.
`ByteBuffersDataOutput(long expectedSize)`	Create a new output, suitable for writing a file of around `expectedSize` bytes.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`copyTo(DataOutput output)`	Copy the current content of this object into another `DataOutput`.
`static ByteBuffersDataOutput`	`newResettableInstance()`
`long`	`ramBytesUsed()`	Return the memory usage of this object in bytes.
`void`	`reset()`	This method resets this object to a clean (zero-size) state and publishes any currently allocated buffers for reuse to the reuse strategy provided in the constructor.
`long`	`size()`
`byte[]`	`toArrayCopy()`	Return a contiguous array with the current content written to the output.
`ArrayList<ByteBuffer>`	`toBufferList()`	Return a list of read-only view of `ByteBuffer` blocks over the current content written to the output.
`ByteBuffersDataInput`	`toDataInput()`	Return a `ByteBuffersDataInput` for the set of current buffers (`toBufferList()`).
`String`	`toString()`
`ArrayList<ByteBuffer>`	`toWriteableBufferList()`	Returns a list of writeable blocks over the (source) content buffers.
`void`	`writeByte(byte b)`	Writes a single byte.
`void`	`writeBytes(byte[] b)`
`void`	`writeBytes(byte[] b, int length)`	Writes an array of bytes.
`void`	`writeBytes(byte[] src, int offset, int length)`	Writes an array of bytes.
`void`	`writeBytes(ByteBuffer buffer)`
`void`	`writeInt(int v)`	Writes an int as four bytes (LE byte order).
`void`	`writeLong(long v)`	Writes a long as eight bytes (LE byte order).
`void`	`writeMapOfStrings(Map<String,String> map)`	Writes a String map.
`void`	`writeSetOfStrings(Set<String> set)`	Writes a String set.
`void`	`writeShort(short v)`	Writes a short as two bytes (LE byte order).
`void`	`writeString(String v)`	Writes a string.

Methods inherited from class org.apache.lucene.store.DataOutput
copyBytes, writeVInt, writeVLong, writeZInt, writeZLong

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

Methods inherited from interface org.apache.lucene.util.Accountable
getChildResources

- Field Detail
  - ALLOCATE_BB_ON_HEAP
```
public static final IntFunction<ByteBuffer> ALLOCATE_BB_ON_HEAP
```
  - NO_REUSE
```
public static final Consumer<ByteBuffer> NO_REUSE
```
    A singleton instance of "no-reuse" buffer strategy.
  - DEFAULT_MIN_BITS_PER_BLOCK
```
public static final int DEFAULT_MIN_BITS_PER_BLOCK
```
    Default minBitsPerBlock
    
    See Also:
    
    Constant Field Values
  - DEFAULT_MAX_BITS_PER_BLOCK
```
public static final int DEFAULT_MAX_BITS_PER_BLOCK
```
    Default maxBitsPerBlock
    
    See Also:
    
    Constant Field Values
  - LIMIT_MIN_BITS_PER_BLOCK
```
public static final int LIMIT_MIN_BITS_PER_BLOCK
```
    Smallest minBitsPerBlock allowed
    
    See Also:
    
    Constant Field Values
  - LIMIT_MAX_BITS_PER_BLOCK
```
public static final int LIMIT_MAX_BITS_PER_BLOCK
```
    Largest maxBitsPerBlock allowed
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - ByteBuffersDataOutput
```
public ByteBuffersDataOutput(long expectedSize)
```
    Create a new output, suitable for writing a file of around expectedSize bytes.
    Memory allocation will be optimized based on the expectedSize hint, so that there is less overhead for larger files.
    
    Parameters:
    
    expectedSize - estimated size of the output file
  - ByteBuffersDataOutput
```
public ByteBuffersDataOutput()
```
    Creates a new output with all defaults.
  - ByteBuffersDataOutput
```
public ByteBuffersDataOutput(int minBitsPerBlock,
                             int maxBitsPerBlock,
                             IntFunction<ByteBuffer> blockAllocate,
                             Consumer<ByteBuffer> blockReuse)
```
    Expert: Creates a new output with custom parameters.
    
    Parameters:
    
    minBitsPerBlock - minimum bits per block
    
    maxBitsPerBlock - maximum bits per block
    
    blockAllocate - block allocator
    
    blockReuse - block recycler
- Method Detail
  - writeByte
```
public void writeByte(byte b)
```
    Description copied from class: DataOutput
    
    Writes a single byte.
    The most primitive data type is an eight-bit byte. Files are accessed as sequences of bytes. All other data types are defined as sequences of bytes, so file formats are byte-order independent.
    
    Specified by:
    
    writeByte in class DataOutput
    
    See Also:
    
    DataInput.readByte()
  - writeBytes
```
public void writeBytes(byte[] src,
                       int offset,
                       int length)
```
    Description copied from class: DataOutput
    
    Writes an array of bytes.
    
    Specified by:
    
    writeBytes in class DataOutput
    
    Parameters:
    
    src - the bytes to write
    
    offset - the offset in the byte array
    
    length - the number of bytes to write
    
    See Also:
    
    DataInput.readBytes(byte[],int,int)
  - writeBytes
```
public void writeBytes(byte[] b,
                       int length)
```
    Description copied from class: DataOutput
    
    Writes an array of bytes.
    
    Overrides:
    
    writeBytes in class DataOutput
    
    Parameters:
    
    b - the bytes to write
    
    length - the number of bytes to write
    
    See Also:
    
    DataInput.readBytes(byte[],int,int)
  - writeBytes
```
public void writeBytes(byte[] b)
```
  - writeBytes
```
public void writeBytes(ByteBuffer buffer)
```
  - toBufferList
```
public ArrayList<ByteBuffer> toBufferList()
```
    Return a list of read-only view of ByteBuffer blocks over the current content written to the output.
  - toWriteableBufferList
```
public ArrayList<ByteBuffer> toWriteableBufferList()
```
    Returns a list of writeable blocks over the (source) content buffers.
    This method returns the raw content of source buffers that may change over the lifetime of this object (blocks can be recycled or discarded, for example). Most applications should favor calling toBufferList() which returns a read-only view over the content of the source buffers.
    The difference between toBufferList() and toWriteableBufferList() is that read-only view of source buffers will always return false from ByteBuffer.hasArray() (which sometimes may be required to avoid double copying).
  - toDataInput
```
public ByteBuffersDataInput toDataInput()
```
    Return a ByteBuffersDataInput for the set of current buffers (toBufferList()).
  - toArrayCopy
```
public byte[] toArrayCopy()
```
    Return a contiguous array with the current content written to the output. The returned array is always a copy (can be mutated).
    If the size() of the underlying buffers exceeds maximum size of Java array, an RuntimeException will be thrown.
  - copyTo
```
public void copyTo(DataOutput output)
            throws IOException
```
    Copy the current content of this object into another DataOutput.
    
    Throws:
    
    IOException
  - size
```
public long size()
```
    Returns:
    
    The number of bytes written to this output so far.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - writeShort
```
public void writeShort(short v)
```
    Description copied from class: DataOutput
    
    Writes a short as two bytes (LE byte order).
    
    Overrides:
    
    writeShort in class DataOutput
    
    See Also:
    
    DataInput.readShort(), BitUtil.VH_LE_SHORT
  - writeInt
```
public void writeInt(int v)
```
    Description copied from class: DataOutput
    
    Writes an int as four bytes (LE byte order).
    
    Overrides:
    
    writeInt in class DataOutput
    
    See Also:
    
    DataInput.readInt(), BitUtil.VH_LE_INT
  - writeLong
```
public void writeLong(long v)
```
    Description copied from class: DataOutput
    
    Writes a long as eight bytes (LE byte order).
    
    Overrides:
    
    writeLong in class DataOutput
    
    See Also:
    
    DataInput.readLong(), BitUtil.VH_LE_LONG
  - writeString
```
public void writeString(String v)
```
    Description copied from class: DataOutput
    
    Writes a string.
    Writes strings as UTF-8 encoded bytes. First the length, in bytes, is written as a VInt, followed by the bytes.
    
    Overrides:
    
    writeString in class DataOutput
    
    See Also:
    
    DataInput.readString()
  - writeMapOfStrings
```
public void writeMapOfStrings(Map<String,String> map)
```
    Description copied from class: DataOutput
    
    Writes a String map.
    First the size is written as an vInt, followed by each key-value pair written as two consecutive Strings.
    
    Overrides:
    
    writeMapOfStrings in class DataOutput
    
    Parameters:
    
    map - Input map.
  - writeSetOfStrings
```
public void writeSetOfStrings(Set<String> set)
```
    Description copied from class: DataOutput
    
    Writes a String set.
    First the size is written as an vInt, followed by each value written as a String.
    
    Overrides:
    
    writeSetOfStrings in class DataOutput
    
    Parameters:
    
    set - Input set.
  - ramBytesUsed
```
public long ramBytesUsed()
```
    Description copied from interface: Accountable
    
    Return the memory usage of this object in bytes. Negative values are illegal.
    
    Specified by:
    
    ramBytesUsed in interface Accountable
  - reset
```
public void reset()
```
    This method resets this object to a clean (zero-size) state and publishes any currently allocated buffers for reuse to the reuse strategy provided in the constructor.
    Sharing byte buffers for reads and writes is dangerous and will very likely lead to hard-to-debug issues, use with great care.
  - newResettableInstance
```
public static ByteBuffersDataOutput newResettableInstance()
```
    Returns:
    
    Returns a new ByteBuffersDataOutput with the reset() capability.

Class ByteBuffersDataOutput

Nested Class Summary

Field Summary

Fields inherited from interface org.apache.lucene.util.Accountable

Constructor Summary

Method Summary

Methods inherited from class org.apache.lucene.store.DataOutput

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.lucene.util.Accountable

Field Detail

ALLOCATE_BB_ON_HEAP

NO_REUSE

DEFAULT_MIN_BITS_PER_BLOCK

DEFAULT_MAX_BITS_PER_BLOCK

LIMIT_MIN_BITS_PER_BLOCK

LIMIT_MAX_BITS_PER_BLOCK

Constructor Detail

ByteBuffersDataOutput

ByteBuffersDataOutput

ByteBuffersDataOutput

Method Detail

writeByte

writeBytes

writeBytes

writeBytes

writeBytes

toBufferList

toWriteableBufferList

toDataInput

toArrayCopy

copyTo

size

toString

writeShort

writeInt

writeLong

writeString

writeMapOfStrings

writeSetOfStrings

ramBytesUsed

reset

newResettableInstance