ByteBufferIndexInput (Lucene 8.9.0 API)乐学网一站式学习平台

java.lang.Object
- org.apache.lucene.store.DataInput
- - org.apache.lucene.store.IndexInput
  - - org.apache.lucene.store.ByteBufferIndexInput

All Implemented Interfaces:

Closeable, AutoCloseable, Cloneable, RandomAccessInput
```
public abstract class ByteBufferIndexInput
extends IndexInput
implements RandomAccessInput
```
Base IndexInput implementation that uses an array of ByteBuffers to represent a file.
Because Java's ByteBuffer uses an int to address the values, it's necessary to access a file greater Integer.MAX_VALUE in size using multiple byte buffers.
For efficiency, this class requires that the buffers are a power-of-two (chunkSizePower).

Field Summary

Fields
Modifier and Type	Field and Description
`protected ByteBuffer[]`	`buffers`
`protected long`	`chunkSizeMask`
`protected int`	`chunkSizePower`
`protected ByteBuffer`	`curBuf`
`protected int`	`curBufIndex`
`protected org.apache.lucene.store.ByteBufferGuard`	`guard`
`protected boolean`	`isClone`
`protected long`	`length`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected ByteBufferIndexInput`	`buildSlice(String sliceDescription, long offset, long length)` Builds the actual sliced IndexInput (may apply extra offset in subclasses).
`ByteBufferIndexInput`	`clone()` Returns a clone of this stream.
`void`	`close()` Closes the stream to further operations.
`long`	`getFilePointer()` Returns the current position in this file, where the next read will occur.
`long`	`length()` The number of bytes in the file.
`protected ByteBufferIndexInput`	`newCloneInstance(String newResourceDescription, ByteBuffer[] newBuffers, int offset, long length)` Factory method that creates a suitable implementation of this class for the given ByteBuffers.
`static ByteBufferIndexInput`	`newInstance(String resourceDescription, ByteBuffer[] buffers, long length, int chunkSizePower, org.apache.lucene.store.ByteBufferGuard guard)`
`byte`	`readByte()` Reads and returns a single byte.
`byte`	`readByte(long pos)` Reads a byte at the given position in the file
`void`	`readBytes(byte[] b, int offset, int len)` Reads a specified number of bytes into an array at the specified offset.
`int`	`readInt()` Reads four bytes and returns an int.
`int`	`readInt(long pos)` Reads an integer at the given position in the file
`void`	`readLELongs(long[] dst, int offset, int length)` Read a specified number of longs with the little endian byte order.
`long`	`readLong()` Reads eight bytes and returns a long.
`long`	`readLong(long pos)` Reads a long at the given position in the file
`short`	`readShort()` Reads two bytes and returns a short.
`short`	`readShort(long pos)` Reads a short at the given position in the file
`void`	`seek(long pos)` Sets current position in this file, where the next read will occur.
`protected void`	`setCurBuf(ByteBuffer curBuf)`
`ByteBufferIndexInput`	`slice(String sliceDescription, long offset, long length)` Creates a slice of this index input, with the given description, offset, and length.

Methods inherited from class org.apache.lucene.store.IndexInput
getFullSliceDescription, randomAccessSlice, toString

Methods inherited from class org.apache.lucene.store.DataInput
readBytes, readMapOfStrings, readSetOfStrings, readString, readVInt, readVLong, readZInt, readZLong, skipBytes

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

- Field Detail
  - length
```
protected final long length
```
  - chunkSizeMask
```
protected final long chunkSizeMask
```
  - chunkSizePower
```
protected final int chunkSizePower
```
  - guard
```
protected final org.apache.lucene.store.ByteBufferGuard guard
```
  - buffers
```
protected ByteBuffer[] buffers
```
  - curBufIndex
```
protected int curBufIndex
```
  - curBuf
```
protected ByteBuffer curBuf
```
  - isClone
```
protected boolean isClone
```
- Method Detail
  - newInstance
```
public static ByteBufferIndexInput newInstance(String resourceDescription,
                                               ByteBuffer[] buffers,
                                               long length,
                                               int chunkSizePower,
                                               org.apache.lucene.store.ByteBufferGuard guard)
```
  - setCurBuf
```
protected void setCurBuf(ByteBuffer curBuf)
```
  - readByte
```
public final byte readByte()
                    throws IOException
```
    Description copied from class: DataInput
    
    Reads and returns a single byte.
    
    Specified by:
    
    readByte in class DataInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataOutput.writeByte(byte)
  - readBytes
```
public final void readBytes(byte[] b,
                            int offset,
                            int len)
                     throws IOException
```
    Description copied from class: DataInput
    
    Reads a specified number of bytes into an array at the specified offset.
    
    Specified by:
    
    readBytes in class DataInput
    
    Parameters:
    
    b - the array to read bytes into
    
    offset - the offset in the array to start storing bytes
    
    len - the number of bytes to read
    
    Throws:
    
    IOException
    
    See Also:
    
    DataOutput.writeBytes(byte[],int)
  - readLELongs
```
public void readLELongs(long[] dst,
                        int offset,
                        int length)
                 throws IOException
```
    Description copied from class: DataInput
    Read a specified number of longs with the little endian byte order.
    This method can be used to read longs whose bytes have been reversed at write time:
```
 for (long l : longs) {
   output.writeLong(Long.reverseBytes(l));
 }
 
```
    Overrides:
    
    readLELongs in class DataInput
    
    Throws:
    
    IOException
  - readShort
```
public final short readShort()
                      throws IOException
```
    Description copied from class: DataInput
    
    Reads two bytes and returns a short.
    
    Overrides:
    
    readShort in class DataInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataOutput.writeByte(byte)
  - readInt
```
public final int readInt()
                  throws IOException
```
    Description copied from class: DataInput
    
    Reads four bytes and returns an int.
    
    Overrides:
    
    readInt in class DataInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataOutput.writeInt(int)
  - readLong
```
public final long readLong()
                    throws IOException
```
    Description copied from class: DataInput
    
    Reads eight bytes and returns a long.
    
    Overrides:
    
    readLong in class DataInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataOutput.writeLong(long)
  - getFilePointer
```
public long getFilePointer()
```
    Description copied from class: IndexInput
    
    Returns the current position in this file, where the next read will occur.
    
    Specified by:
    
    getFilePointer in class IndexInput
    
    See Also:
    
    IndexInput.seek(long)
  - seek
```
public void seek(long pos)
          throws IOException
```
    Description copied from class: IndexInput
    
    Sets current position in this file, where the next read will occur. If this is beyond the end of the file then this will throw EOFException and then the stream is in an undetermined state.
    
    Specified by:
    
    seek in class IndexInput
    
    Throws:
    
    IOException
    
    See Also:
    
    IndexInput.getFilePointer()
  - readByte
```
public byte readByte(long pos)
              throws IOException
```
    Description copied from interface: RandomAccessInput
    
    Reads a byte at the given position in the file
    
    Specified by:
    
    readByte in interface RandomAccessInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataInput.readByte()
  - readShort
```
public short readShort(long pos)
                throws IOException
```
    Description copied from interface: RandomAccessInput
    
    Reads a short at the given position in the file
    
    Specified by:
    
    readShort in interface RandomAccessInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataInput.readShort()
  - readInt
```
public int readInt(long pos)
            throws IOException
```
    Description copied from interface: RandomAccessInput
    
    Reads an integer at the given position in the file
    
    Specified by:
    
    readInt in interface RandomAccessInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataInput.readInt()
  - readLong
```
public long readLong(long pos)
              throws IOException
```
    Description copied from interface: RandomAccessInput
    
    Reads a long at the given position in the file
    
    Specified by:
    
    readLong in interface RandomAccessInput
    
    Throws:
    
    IOException
    
    See Also:
    
    DataInput.readLong()
  - length
```
public final long length()
```
    Description copied from class: IndexInput
    
    The number of bytes in the file.
    
    Specified by:
    
    length in class IndexInput
  - clone
```
public final ByteBufferIndexInput clone()
```
    Description copied from class: IndexInput
    
    Returns a clone of this stream.
    Clones of a stream access the same data, and are positioned at the same point as the stream they were cloned from.
    Expert: Subclasses must ensure that clones may be positioned at different points in the input from each other and from the stream they were cloned from.
    Warning: Lucene never closes cloned IndexInputs, it will only call IndexInput.close() on the original object.
    If you access the cloned IndexInput after closing the original object, any readXXX methods will throw AlreadyClosedException.
    This method is NOT thread safe, so if the current IndexInput is being used by one thread while clone is called by another, disaster could strike.
    
    Overrides:
    
    clone in class IndexInput
  - slice
```
public final ByteBufferIndexInput slice(String sliceDescription,
                                        long offset,
                                        long length)
```
    Creates a slice of this index input, with the given description, offset, and length. The slice is seeked to the beginning.
    
    Specified by:
    
    slice in class IndexInput
  - buildSlice
```
protected ByteBufferIndexInput buildSlice(String sliceDescription,
                                          long offset,
                                          long length)
```
    Builds the actual sliced IndexInput (may apply extra offset in subclasses).
  - newCloneInstance
```
protected ByteBufferIndexInput newCloneInstance(String newResourceDescription,
                                                ByteBuffer[] newBuffers,
                                                int offset,
                                                long length)
```
    Factory method that creates a suitable implementation of this class for the given ByteBuffers.
  - close
```
public final void close()
                 throws IOException
```
    Description copied from class: IndexInput
    
    Closes the stream to further operations.
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in class IndexInput
    
    Throws:
    
    IOException

Class ByteBufferIndexInput

Field Summary

Method Summary

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

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

Methods inherited from class java.lang.Object

Field Detail

length

chunkSizeMask

chunkSizePower

guard

buffers

curBufIndex

curBuf

isClone

Method Detail

newInstance

setCurBuf

readByte

readBytes

readLELongs

readShort

readInt

readLong

getFilePointer

seek

readByte

readShort

readInt

readLong

length

clone

slice

buildSlice

newCloneInstance

close