Note that for simple usage, {@link NumericField} is + * recommended. {@link NumericField} disables norms and + * term freqs, as they are not usually needed during + * searching. If you need to change these settings, you + * should use this class. + * + *
See {@link NumericField} for capabilities of fields + * indexed numerically.
+ * + *Here's an example usage, for an int field:
+ *
+ *
+ * Field field = new Field(name, new NumericTokenStream(precisionStep).setIntValue(value)); + * field.setOmitNorms(true); + * field.setIndexOptions(IndexOptions.DOCS_ONLY); + * document.add(field); + *+ * + *
For optimal performance, re-use the TokenStream and Field instance + * for more than one document: + * + *
+ * NumericTokenStream stream = new NumericTokenStream(precisionStep);
+ * Field field = new Field(name, stream);
+ * field.setOmitNorms(true);
+ * field.setIndexOptions(IndexOptions.DOCS_ONLY);
+ * Document document = new Document();
+ * document.add(field);
+ *
+ * for(all documents) {
+ * stream.setIntValue(value)
+ * writer.addDocument(document);
+ * }
+ *
+ *
+ * This stream is not intended to be used in analyzers; + * it's more for iterating the different precisions during + * indexing a specific numeric value.
+ + *NOTE: as token streams are only consumed once
+ * the document is added to the index, if you index more
+ * than one numeric field, use a separate NumericTokenStream
+ * instance for each.
See {@link NumericRangeQuery} for more details on the
+ * precisionStep
+ * parameter as well as how numeric fields work under the hood.
precisionStep
+ * {@link NumericUtils#PRECISION_STEP_DEFAULT} (4). The stream is not yet initialized,
+ * before using set a value using the various set???Value() methods.
+ */
+ public NumericTokenStream() {
+ this(NumericUtils.PRECISION_STEP_DEFAULT);
+ }
+
+ /**
+ * Creates a token stream for numeric values with the specified
+ * precisionStep. The stream is not yet initialized,
+ * before using set a value using the various set???Value() methods.
+ */
+ public NumericTokenStream(final int precisionStep) {
+ super();
+ this.precisionStep = precisionStep;
+ if (precisionStep < 1)
+ throw new IllegalArgumentException("precisionStep must be >=1");
+ }
+
+ /**
+ * Expert: Creates a token stream for numeric values with the specified
+ * precisionStep using the given {@link AttributeSource}.
+ * The stream is not yet initialized,
+ * before using set a value using the various set???Value() methods.
+ */
+ public NumericTokenStream(AttributeSource source, final int precisionStep) {
+ super(source);
+ this.precisionStep = precisionStep;
+ if (precisionStep < 1)
+ throw new IllegalArgumentException("precisionStep must be >=1");
+ }
+
+ /**
+ * Expert: Creates a token stream for numeric values with the specified
+ * precisionStep using the given
+ * {@link org.apache.lucene.util.AttributeSource.AttributeFactory}.
+ * The stream is not yet initialized,
+ * before using set a value using the various set???Value() methods.
+ */
+ public NumericTokenStream(AttributeFactory factory, final int precisionStep) {
+ super(factory);
+ this.precisionStep = precisionStep;
+ if (precisionStep < 1)
+ throw new IllegalArgumentException("precisionStep must be >=1");
+ }
+
+ /**
+ * Initializes the token stream with the supplied long value.
+ * @param value the value, for which this TokenStream should enumerate tokens.
+ * @return this instance, because of this you can use it the following way:
+ * new Field(name, new NumericTokenStream(precisionStep).setLongValue(value))
+ */
+ public NumericTokenStream setLongValue(final long value) {
+ this.value = value;
+ valSize = 64;
+ shift = 0;
+ return this;
+ }
+
+ /**
+ * Initializes the token stream with the supplied int value.
+ * @param value the value, for which this TokenStream should enumerate tokens.
+ * @return this instance, because of this you can use it the following way:
+ * new Field(name, new NumericTokenStream(precisionStep).setIntValue(value))
+ */
+ public NumericTokenStream setIntValue(final int value) {
+ this.value = value;
+ valSize = 32;
+ shift = 0;
+ return this;
+ }
+
+ /**
+ * Initializes the token stream with the supplied double value.
+ * @param value the value, for which this TokenStream should enumerate tokens.
+ * @return this instance, because of this you can use it the following way:
+ * new Field(name, new NumericTokenStream(precisionStep).setDoubleValue(value))
+ */
+ public NumericTokenStream setDoubleValue(final double value) {
+ this.value = NumericUtils.doubleToSortableLong(value);
+ valSize = 64;
+ shift = 0;
+ return this;
+ }
+
+ /**
+ * Initializes the token stream with the supplied float value.
+ * @param value the value, for which this TokenStream should enumerate tokens.
+ * @return this instance, because of this you can use it the following way:
+ * new Field(name, new NumericTokenStream(precisionStep).setFloatValue(value))
+ */
+ public NumericTokenStream setFloatValue(final float value) {
+ this.value = NumericUtils.floatToSortableInt(value);
+ valSize = 32;
+ shift = 0;
+ return this;
+ }
+
+ @Override
+ public void reset() {
+ if (valSize == 0)
+ throw new IllegalStateException("call set???Value() before usage");
+ shift = 0;
+ }
+
+ @Override
+ public boolean incrementToken() {
+ if (valSize == 0)
+ throw new IllegalStateException("call set???Value() before usage");
+ if (shift >= valSize)
+ return false;
+
+ clearAttributes();
+ final char[] buffer;
+ switch (valSize) {
+ case 64:
+ buffer = termAtt.resizeBuffer(NumericUtils.BUF_SIZE_LONG);
+ termAtt.setLength(NumericUtils.longToPrefixCoded(value, shift, buffer));
+ break;
+
+ case 32:
+ buffer = termAtt.resizeBuffer(NumericUtils.BUF_SIZE_INT);
+ termAtt.setLength(NumericUtils.intToPrefixCoded((int) value, shift, buffer));
+ break;
+
+ default:
+ // should not happen
+ throw new IllegalArgumentException("valSize must be 32 or 64");
+ }
+
+ typeAtt.setType((shift == 0) ? TOKEN_TYPE_FULL_PREC : TOKEN_TYPE_LOWER_PREC);
+ posIncrAtt.setPositionIncrement((shift == 0) ? 1 : 0);
+ shift += precisionStep;
+ return true;
+ }
+
+ @Override
+ public String toString() {
+ final StringBuilder sb = new StringBuilder("(numeric,valSize=").append(valSize);
+ sb.append(",precisionStep=").append(precisionStep).append(')');
+ return sb.toString();
+ }
+
+ /** Returns the precision step. */
+ public int getPrecisionStep() {
+ return precisionStep;
+ }
+
+ // members
+ private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class);
+ private final TypeAttribute typeAtt = addAttribute(TypeAttribute.class);
+ private final PositionIncrementAttribute posIncrAtt = addAttribute(PositionIncrementAttribute.class);
+
+ private int shift = 0, valSize = 0; // valSize==0 means not initialized
+ private final int precisionStep;
+
+ private long value = 0L;
+}