/**
* Serializes the data set to file using the following format:
*
* <ul>
* <li>FuzzySet -->FuzzySetVersion,HashFunctionName,BloomSize,
* NumBitSetWords,BitSetWord<sup>NumBitSetWords</sup>
* <li>HashFunctionName --> {@link DataOutput#writeString(String) String} The name of a
* ServiceProvider registered {@link HashFunction}
* <li>FuzzySetVersion --> {@link DataOutput#writeInt Uint32} The version number of the
* {@link FuzzySet} class
* <li>BloomSize --> {@link DataOutput#writeInt Uint32} The modulo value used to project
* hashes into the field's Bitset
* <li>NumBitSetWords --> {@link DataOutput#writeInt Uint32} The number of longs (as returned
* from {@link FixedBitSet#getBits})
* <li>BitSetWord --> {@link DataOutput#writeLong Long} A long from the array returned by
* {@link FixedBitSet#getBits}
* </ul>
*
* @param out Data output stream
* @throws IOException If there is a low-level I/O error
*/
public void serialize(DataOutput out) throws IOException {
out.writeInt(VERSION_CURRENT);
out.writeInt(bloomSize);
long[] bits = filter.getBits();
out.writeInt(bits.length);
for (int i = 0; i < bits.length; i++) {
// Can't used VLong encoding because cant cope with negative numbers
// output by FixedBitSet
out.writeLong(bits[i]);
}
}
private void writeRecursively(DataOutput out, TSTNode node) throws IOException {
if (node == null) {
return;
}
out.writeString(new String(new char[] {node.splitchar}, 0, 1));
byte mask = 0;
if (node.relatives[TSTNode.LOKID] != null) mask |= LO_KID;
if (node.relatives[TSTNode.EQKID] != null) mask |= EQ_KID;
if (node.relatives[TSTNode.HIKID] != null) mask |= HI_KID;
if (node.data != null) mask |= HAS_VALUE;
out.writeByte(mask);
if (node.data != null) {
out.writeLong(((Number) node.data).longValue());
}
writeRecursively(out, node.relatives[TSTNode.LOKID]);
writeRecursively(out, node.relatives[TSTNode.EQKID]);
writeRecursively(out, node.relatives[TSTNode.HIKID]);
}
// pre-order traversal
private void writeRecursively(DataOutput out, TernaryTreeNode node) throws IOException {
// write out the current node
out.writeString(new String(new char[] {node.splitchar}, 0, 1));
// prepare a mask of kids
byte mask = 0;
if (node.eqKid != null) mask |= EQ_KID;
if (node.loKid != null) mask |= LO_KID;
if (node.hiKid != null) mask |= HI_KID;
if (node.token != null) mask |= HAS_TOKEN;
if (node.val != null) mask |= HAS_VALUE;
out.writeByte(mask);
if (node.token != null) out.writeString(node.token);
if (node.val != null) out.writeLong(((Number) node.val).longValue());
// recurse and write kids
if (node.loKid != null) {
writeRecursively(out, node.loKid);
}
if (node.eqKid != null) {
writeRecursively(out, node.eqKid);
}
if (node.hiKid != null) {
writeRecursively(out, node.hiKid);
}
}