--- /dev/null
+package org.apache.lucene.search;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.io.IOException;
+import java.io.Serializable;
+import java.util.Locale;
+
+import org.apache.lucene.util.StringHelper;
+
+/**
+ * Stores information about how to sort documents by terms in an individual
+ * field. Fields must be indexed in order to sort by them.
+ *
+ * <p>Created: Feb 11, 2004 1:25:29 PM
+ *
+ * @since lucene 1.4
+ * @see Sort
+ */
+public class SortField
+implements Serializable {
+
+ /** Sort by document score (relevance). Sort values are Float and higher
+ * values are at the front. */
+ public static final int SCORE = 0;
+
+ /** Sort by document number (index order). Sort values are Integer and lower
+ * values are at the front. */
+ public static final int DOC = 1;
+
+ // reserved, in Lucene 2.9, there was a constant: AUTO = 2;
+
+ /** Sort using term values as Strings. Sort values are String and lower
+ * values are at the front. */
+ public static final int STRING = 3;
+
+ /** Sort using term values as encoded Integers. Sort values are Integer and
+ * lower values are at the front. */
+ public static final int INT = 4;
+
+ /** Sort using term values as encoded Floats. Sort values are Float and
+ * lower values are at the front. */
+ public static final int FLOAT = 5;
+
+ /** Sort using term values as encoded Longs. Sort values are Long and
+ * lower values are at the front. */
+ public static final int LONG = 6;
+
+ /** Sort using term values as encoded Doubles. Sort values are Double and
+ * lower values are at the front. */
+ public static final int DOUBLE = 7;
+
+ /** Sort using term values as encoded Shorts. Sort values are Short and
+ * lower values are at the front. */
+ public static final int SHORT = 8;
+
+ /** Sort using a custom Comparator. Sort values are any Comparable and
+ * sorting is done according to natural order. */
+ public static final int CUSTOM = 9;
+
+ /** Sort using term values as encoded Bytes. Sort values are Byte and
+ * lower values are at the front. */
+ public static final int BYTE = 10;
+
+ /** Sort using term values as Strings, but comparing by
+ * value (using String.compareTo) for all comparisons.
+ * This is typically slower than {@link #STRING}, which
+ * uses ordinals to do the sorting. */
+ public static final int STRING_VAL = 11;
+
+ // IMPLEMENTATION NOTE: the FieldCache.STRING_INDEX is in the same "namespace"
+ // as the above static int values. Any new values must not have the same value
+ // as FieldCache.STRING_INDEX.
+
+ /** Represents sorting by document score (relevance). */
+ public static final SortField FIELD_SCORE = new SortField(null, SCORE);
+
+ /** Represents sorting by document number (index order). */
+ public static final SortField FIELD_DOC = new SortField(null, DOC);
+
+ private String field;
+ private int type; // defaults to determining type dynamically
+ private Locale locale; // defaults to "natural order" (no Locale)
+ boolean reverse = false; // defaults to natural order
+ private FieldCache.Parser parser;
+
+ // Used for CUSTOM sort
+ private FieldComparatorSource comparatorSource;
+
+ private Object missingValue;
+
+ /** Creates a sort by terms in the given field with the type of term
+ * values explicitly given.
+ * @param field Name of field to sort by. Can be <code>null</code> if
+ * <code>type</code> is SCORE or DOC.
+ * @param type Type of values in the terms.
+ */
+ public SortField(String field, int type) {
+ initFieldType(field, type);
+ }
+
+ /** Creates a sort, possibly in reverse, by terms in the given field with the
+ * type of term values explicitly given.
+ * @param field Name of field to sort by. Can be <code>null</code> if
+ * <code>type</code> is SCORE or DOC.
+ * @param type Type of values in the terms.
+ * @param reverse True if natural order should be reversed.
+ */
+ public SortField(String field, int type, boolean reverse) {
+ initFieldType(field, type);
+ this.reverse = reverse;
+ }
+
+ /** Creates a sort by terms in the given field, parsed
+ * to numeric values using a custom {@link FieldCache.Parser}.
+ * @param field Name of field to sort by. Must not be null.
+ * @param parser Instance of a {@link FieldCache.Parser},
+ * which must subclass one of the existing numeric
+ * parsers from {@link FieldCache}. Sort type is inferred
+ * by testing which numeric parser the parser subclasses.
+ * @throws IllegalArgumentException if the parser fails to
+ * subclass an existing numeric parser, or field is null
+ */
+ public SortField(String field, FieldCache.Parser parser) {
+ this(field, parser, false);
+ }
+
+ /** Creates a sort, possibly in reverse, by terms in the given field, parsed
+ * to numeric values using a custom {@link FieldCache.Parser}.
+ * @param field Name of field to sort by. Must not be null.
+ * @param parser Instance of a {@link FieldCache.Parser},
+ * which must subclass one of the existing numeric
+ * parsers from {@link FieldCache}. Sort type is inferred
+ * by testing which numeric parser the parser subclasses.
+ * @param reverse True if natural order should be reversed.
+ * @throws IllegalArgumentException if the parser fails to
+ * subclass an existing numeric parser, or field is null
+ */
+ public SortField(String field, FieldCache.Parser parser, boolean reverse) {
+ if (parser instanceof FieldCache.IntParser) initFieldType(field, INT);
+ else if (parser instanceof FieldCache.FloatParser) initFieldType(field, FLOAT);
+ else if (parser instanceof FieldCache.ShortParser) initFieldType(field, SHORT);
+ else if (parser instanceof FieldCache.ByteParser) initFieldType(field, BYTE);
+ else if (parser instanceof FieldCache.LongParser) initFieldType(field, LONG);
+ else if (parser instanceof FieldCache.DoubleParser) initFieldType(field, DOUBLE);
+ else
+ throw new IllegalArgumentException("Parser instance does not subclass existing numeric parser from FieldCache (got " + parser + ")");
+
+ this.reverse = reverse;
+ this.parser = parser;
+ }
+
+ /** Creates a sort by terms in the given field sorted
+ * according to the given locale.
+ * @param field Name of field to sort by, cannot be <code>null</code>.
+ * @param locale Locale of values in the field.
+ */
+ public SortField (String field, Locale locale) {
+ initFieldType(field, STRING);
+ this.locale = locale;
+ }
+
+ /** Creates a sort, possibly in reverse, by terms in the given field sorted
+ * according to the given locale.
+ * @param field Name of field to sort by, cannot be <code>null</code>.
+ * @param locale Locale of values in the field.
+ */
+ public SortField (String field, Locale locale, boolean reverse) {
+ initFieldType(field, STRING);
+ this.locale = locale;
+ this.reverse = reverse;
+ }
+
+ /** Creates a sort with a custom comparison function.
+ * @param field Name of field to sort by; cannot be <code>null</code>.
+ * @param comparator Returns a comparator for sorting hits.
+ */
+ public SortField(String field, FieldComparatorSource comparator) {
+ initFieldType(field, CUSTOM);
+ this.comparatorSource = comparator;
+ }
+
+ /** Creates a sort, possibly in reverse, with a custom comparison function.
+ * @param field Name of field to sort by; cannot be <code>null</code>.
+ * @param comparator Returns a comparator for sorting hits.
+ * @param reverse True if natural order should be reversed.
+ */
+ public SortField(String field, FieldComparatorSource comparator, boolean reverse) {
+ initFieldType(field, CUSTOM);
+ this.reverse = reverse;
+ this.comparatorSource = comparator;
+ }
+
+ /** Set a default sorting value for documents which lacks one */
+ public SortField setMissingValue(Object missingValue) {
+ if (type != BYTE && type != SHORT && type != INT && type != FLOAT && type != LONG && type != DOUBLE) {
+ throw new IllegalArgumentException( "Missing value only works for numeric types" );
+ }
+ this.missingValue = missingValue;
+
+ return this;
+ }
+
+ // Sets field & type, and ensures field is not NULL unless
+ // type is SCORE or DOC
+ private void initFieldType(String field, int type) {
+ this.type = type;
+ if (field == null) {
+ if (type != SCORE && type != DOC)
+ throw new IllegalArgumentException("field can only be null when type is SCORE or DOC");
+ } else {
+ this.field = StringHelper.intern(field);
+ }
+ }
+
+ /** Returns the name of the field. Could return <code>null</code>
+ * if the sort is by SCORE or DOC.
+ * @return Name of field, possibly <code>null</code>.
+ */
+ public String getField() {
+ return field;
+ }
+
+ /** Returns the type of contents in the field.
+ * @return One of the constants SCORE, DOC, STRING, INT or FLOAT.
+ */
+ public int getType() {
+ return type;
+ }
+
+ /** Returns the Locale by which term values are interpreted.
+ * May return <code>null</code> if no Locale was specified.
+ * @return Locale, or <code>null</code>.
+ */
+ public Locale getLocale() {
+ return locale;
+ }
+
+ /** Returns the instance of a {@link FieldCache} parser that fits to the given sort type.
+ * May return <code>null</code> if no parser was specified. Sorting is using the default parser then.
+ * @return An instance of a {@link FieldCache} parser, or <code>null</code>.
+ */
+ public FieldCache.Parser getParser() {
+ return parser;
+ }
+
+ /** Returns whether the sort should be reversed.
+ * @return True if natural order should be reversed.
+ */
+ public boolean getReverse() {
+ return reverse;
+ }
+
+ /** Returns the {@link FieldComparatorSource} used for
+ * custom sorting
+ */
+ public FieldComparatorSource getComparatorSource() {
+ return comparatorSource;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder buffer = new StringBuilder();
+ switch (type) {
+ case SCORE:
+ buffer.append("<score>");
+ break;
+
+ case DOC:
+ buffer.append("<doc>");
+ break;
+
+ case STRING:
+ buffer.append("<string: \"").append(field).append("\">");
+ break;
+
+ case STRING_VAL:
+ buffer.append("<string_val: \"").append(field).append("\">");
+ break;
+
+ case BYTE:
+ buffer.append("<byte: \"").append(field).append("\">");
+ break;
+
+ case SHORT:
+ buffer.append("<short: \"").append(field).append("\">");
+ break;
+
+ case INT:
+ buffer.append("<int: \"").append(field).append("\">");
+ break;
+
+ case LONG:
+ buffer.append("<long: \"").append(field).append("\">");
+ break;
+
+ case FLOAT:
+ buffer.append("<float: \"").append(field).append("\">");
+ break;
+
+ case DOUBLE:
+ buffer.append("<double: \"").append(field).append("\">");
+ break;
+
+ case CUSTOM:
+ buffer.append("<custom:\"").append(field).append("\": ").append(comparatorSource).append('>');
+ break;
+
+ default:
+ buffer.append("<???: \"").append(field).append("\">");
+ break;
+ }
+
+ if (locale != null) buffer.append('(').append(locale).append(')');
+ if (parser != null) buffer.append('(').append(parser).append(')');
+ if (reverse) buffer.append('!');
+
+ return buffer.toString();
+ }
+
+ /** Returns true if <code>o</code> is equal to this. If a
+ * {@link FieldComparatorSource} or {@link
+ * FieldCache.Parser} was provided, it must properly
+ * implement equals (unless a singleton is always used). */
+ @Override
+ public boolean equals(Object o) {
+ if (this == o) return true;
+ if (!(o instanceof SortField)) return false;
+ final SortField other = (SortField)o;
+ return (
+ other.field == this.field // field is always interned
+ && other.type == this.type
+ && other.reverse == this.reverse
+ && (other.locale == null ? this.locale == null : other.locale.equals(this.locale))
+ && (other.comparatorSource == null ? this.comparatorSource == null : other.comparatorSource.equals(this.comparatorSource))
+ && (other.parser == null ? this.parser == null : other.parser.equals(this.parser))
+ );
+ }
+
+ /** Returns true if <code>o</code> is equal to this. If a
+ * {@link FieldComparatorSource} or {@link
+ * FieldCache.Parser} was provided, it must properly
+ * implement hashCode (unless a singleton is always
+ * used). */
+ @Override
+ public int hashCode() {
+ int hash=type^0x346565dd + Boolean.valueOf(reverse).hashCode()^0xaf5998bb;
+ if (field != null) hash += field.hashCode()^0xff5685dd;
+ if (locale != null) hash += locale.hashCode()^0x08150815;
+ if (comparatorSource != null) hash += comparatorSource.hashCode();
+ if (parser != null) hash += parser.hashCode()^0x3aaf56ff;
+ return hash;
+ }
+
+ // field must be interned after reading from stream
+ private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException {
+ in.defaultReadObject();
+ if (field != null)
+ field = StringHelper.intern(field);
+ }
+
+ /** Returns the {@link FieldComparator} to use for
+ * sorting.
+ *
+ * @lucene.experimental
+ *
+ * @param numHits number of top hits the queue will store
+ * @param sortPos position of this SortField within {@link
+ * Sort}. The comparator is primary if sortPos==0,
+ * secondary if sortPos==1, etc. Some comparators can
+ * optimize themselves when they are the primary sort.
+ * @return {@link FieldComparator} to use when sorting
+ */
+ public FieldComparator getComparator(final int numHits, final int sortPos) throws IOException {
+
+ if (locale != null) {
+ // TODO: it'd be nice to allow FieldCache.getStringIndex
+ // to optionally accept a Locale so sorting could then use
+ // the faster StringComparator impls
+ return new FieldComparator.StringComparatorLocale(numHits, field, locale);
+ }
+
+ switch (type) {
+ case SortField.SCORE:
+ return new FieldComparator.RelevanceComparator(numHits);
+
+ case SortField.DOC:
+ return new FieldComparator.DocComparator(numHits);
+
+ case SortField.INT:
+ return new FieldComparator.IntComparator(numHits, field, parser, (Integer) missingValue);
+
+ case SortField.FLOAT:
+ return new FieldComparator.FloatComparator(numHits, field, parser, (Float) missingValue);
+
+ case SortField.LONG:
+ return new FieldComparator.LongComparator(numHits, field, parser, (Long) missingValue);
+
+ case SortField.DOUBLE:
+ return new FieldComparator.DoubleComparator(numHits, field, parser, (Double) missingValue);
+
+ case SortField.BYTE:
+ return new FieldComparator.ByteComparator(numHits, field, parser, (Byte) missingValue);
+
+ case SortField.SHORT:
+ return new FieldComparator.ShortComparator(numHits, field, parser, (Short) missingValue);
+
+ case SortField.CUSTOM:
+ assert comparatorSource != null;
+ return comparatorSource.newComparator(field, numHits, sortPos, reverse);
+
+ case SortField.STRING:
+ return new FieldComparator.StringOrdValComparator(numHits, field, sortPos, reverse);
+
+ case SortField.STRING_VAL:
+ return new FieldComparator.StringValComparator(numHits, field);
+
+ default:
+ throw new IllegalStateException("Illegal sort type: " + type);
+ }
+ }
+}
fnp / pylucene.git / blobdiff