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org.apache.lucene.index
public class: Payload [javadoc | source]

java.lang.Object
   org.apache.lucene.index.Payload

All Implemented Interfaces:
    Cloneable, Serializable

A Payload is metadata that can be stored together with each occurrence of a term. This metadata is stored inline in the posting list of the specific term.

To store payloads in the index a TokenStream has to be used that produces Token s containing payload data.

Use TermPositions#getPayloadLength() and TermPositions#getPayload(byte[], int) to retrieve the payloads from the index.

Field Summary
protected  byte[]	data	the byte array containing the payload data
protected  int	offset	the offset within the byte array
protected  int	length	the length of the payload data

Constructor:
public Payload() { // nothing to do } Creates an empty payload and does not allocate a byte array.
public Payload(byte[] data) { this(data, 0, data.length); } Creates a new payload with the the given array as data. A reference to the passed-in array is held, i. e. no copy is made. Parameters: data - the data of this payload
public Payload(byte[] data, int offset, int length) { if (offset < 0 || offset + length > data.length) { throw new IllegalArgumentException(); } this.data = data; this.offset = offset; this.length = length; } Creates a new payload with the the given array as data. A reference to the passed-in array is held, i. e. no copy is made. Parameters: data - the data of this payload offset - the offset in the data byte array length - the length of the data

Method from org.apache.lucene.index.Payload Summary:
byteAt,   clone,   copyTo,   equals,   getData,   getOffset,   hashCode,   length,   setData,   setData,   toByteArray

Methods from java.lang.Object:
equals,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait

Method from org.apache.lucene.index.Payload Detail:
public byte byteAt(int index) { if (0 < = index && index < this.length) { return this.data[this.offset + index]; } throw new ArrayIndexOutOfBoundsException(index); } Returns the byte at the given index.
public Object clone() { try { // Start with a shallow copy of data Payload clone = (Payload) super.clone(); // Only copy the part of data that belongs to this Payload if (offset == 0 && length == data.length) { // It is the whole thing, so just clone it. clone.data = (byte[]) data.clone(); } else { // Just get the part clone.data = this.toByteArray(); clone.offset = 0; } return clone; } catch (CloneNotSupportedException e) { throw new RuntimeException(e); // shouldn't happen } } Clones this payload by creating a copy of the underlying byte array.
public void copyTo(byte[] target, int targetOffset) { if (this.length > target.length + targetOffset) { throw new ArrayIndexOutOfBoundsException(); } System.arraycopy(this.data, this.offset, target, targetOffset, this.length); } Copies the payload data to a byte array.
public boolean equals(Object obj) { if (obj == this) return true; if (obj instanceof Payload) { Payload other = (Payload) obj; if (length == other.length) { for(int i=0;i< length;i++) if (data[offset+i] != other.data[other.offset+i]) return false; return true; } else return false; } else return false; }
public byte[] getData() { return this.data; } Returns a reference to the underlying byte array that holds this payloads data.
public int getOffset() { return this.offset; } Returns the offset in the underlying byte array
public int hashCode() { return ArrayUtil.hashCode(data, offset, offset+length); }
public int length() { return this.length; } Returns the length of the payload data.
public void setData(byte[] data) { setData(data, 0, data.length); } Sets this payloads data. A reference to the passed-in array is held, i. e. no copy is made.
public void setData(byte[] data, int offset, int length) { this.data = data; this.offset = offset; this.length = length; } Sets this payloads data. A reference to the passed-in array is held, i. e. no copy is made.
public byte[] toByteArray() { byte[] retArray = new byte[this.length]; System.arraycopy(this.data, this.offset, retArray, 0, this.length); return retArray; } Allocates a new byte array, copies the payload data into it and returns it.