Module org.apache.lucene.core
Package org.apache.lucene.util

Class PagedBytes

java.lang.Object
org.apache.lucene.util.PagedBytes
All Implemented Interfaces:
Accountable
public final class PagedBytes extends Object implements Accountable
Represents a logical byte[] as a series of pages. You can write-once into the logical byte[] (append only), using copy, and then retrieve slices (BytesRef) into it using fill.

  • Field Details

    • BASE_RAM_BYTES_USED

      private static final long BASE_RAM_BYTES_USED

    • blocks

      private byte[][] blocks

    • numBlocks

      private int numBlocks

    • blockSize

      private final int blockSize

    • blockBits

      private final int blockBits

    • blockMask

      private final int blockMask

    • didSkipBytes

      private boolean didSkipBytes

    • frozen

      private boolean frozen

    • upto

      private int upto

    • currentBlock

      private byte[] currentBlock

    • bytesUsedPerBlock

      private final long bytesUsedPerBlock

    • EMPTY_BYTES

      private static final byte[] EMPTY_BYTES

  • Constructor Details

    • PagedBytes

      public PagedBytes(int blockBits)
      1<<blockBits must be bigger than biggest single BytesRef slice that will be pulled

  • Method Details

    • addBlock

      private void addBlock(byte[] block)

    • copy

      public void copy(IndexInput in, long byteCount) throws IOException
      Read this many bytes from in
      Throws:
      IOException

    • copy

      public void copy(BytesRef bytes, BytesRef out)
      Copy BytesRef in, setting BytesRef out to the result. Do not use this if you will use freeze(true). This only supports bytes.length <= blockSize

    • freeze

      public PagedBytes.Reader freeze(boolean trim)
      Commits final byte[], trimming it if necessary and if trim=true

    • getPointer

      public long getPointer()

    • 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

    • copyUsingLengthPrefix

      public long copyUsingLengthPrefix(BytesRef bytes)
      Copy bytes in, writing the length as a 1 or 2 byte vInt prefix.

    • getDataInput

      public PagedBytes.PagedBytesDataInput getDataInput()
      Returns a DataInput to read values from this PagedBytes instance.

    • getDataOutput

      public PagedBytes.PagedBytesDataOutput getDataOutput()
      Returns a DataOutput that you may use to write into this PagedBytes instance. If you do this, you should not call the other writing methods (eg, copy); results are undefined.