--- /dev/null
+package org.apache.lucene.search.spans;
+
+/**
+ * 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.util.List;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.Set;
+
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.index.Term;
+import org.apache.lucene.search.Query;
+import org.apache.lucene.util.ToStringUtils;
+
+/** Matches spans which are near one another. One can specify <i>slop</i>, the
+ * maximum number of intervening unmatched positions, as well as whether
+ * matches are required to be in-order. */
+public class SpanNearQuery extends SpanQuery implements Cloneable {
+ protected List<SpanQuery> clauses;
+ protected int slop;
+ protected boolean inOrder;
+
+ protected String field;
+ private boolean collectPayloads;
+
+ /** Construct a SpanNearQuery. Matches spans matching a span from each
+ * clause, with up to <code>slop</code> total unmatched positions between
+ * them. * When <code>inOrder</code> is true, the spans from each clause
+ * must be * ordered as in <code>clauses</code>.
+ * @param clauses the clauses to find near each other
+ * @param slop The slop value
+ * @param inOrder true if order is important
+ * */
+ public SpanNearQuery(SpanQuery[] clauses, int slop, boolean inOrder) {
+ this(clauses, slop, inOrder, true);
+ }
+
+ public SpanNearQuery(SpanQuery[] clauses, int slop, boolean inOrder, boolean collectPayloads) {
+
+ // copy clauses array into an ArrayList
+ this.clauses = new ArrayList<SpanQuery>(clauses.length);
+ for (int i = 0; i < clauses.length; i++) {
+ SpanQuery clause = clauses[i];
+ if (i == 0) { // check field
+ field = clause.getField();
+ } else if (!clause.getField().equals(field)) {
+ throw new IllegalArgumentException("Clauses must have same field.");
+ }
+ this.clauses.add(clause);
+ }
+ this.collectPayloads = collectPayloads;
+ this.slop = slop;
+ this.inOrder = inOrder;
+ }
+
+ /** Return the clauses whose spans are matched. */
+ public SpanQuery[] getClauses() {
+ return clauses.toArray(new SpanQuery[clauses.size()]);
+ }
+
+ /** Return the maximum number of intervening unmatched positions permitted.*/
+ public int getSlop() { return slop; }
+
+ /** Return true if matches are required to be in-order.*/
+ public boolean isInOrder() { return inOrder; }
+
+ @Override
+ public String getField() { return field; }
+
+ @Override
+ public void extractTerms(Set<Term> terms) {
+ for (final SpanQuery clause : clauses) {
+ clause.extractTerms(terms);
+ }
+ }
+
+
+ @Override
+ public String toString(String field) {
+ StringBuilder buffer = new StringBuilder();
+ buffer.append("spanNear([");
+ Iterator<SpanQuery> i = clauses.iterator();
+ while (i.hasNext()) {
+ SpanQuery clause = i.next();
+ buffer.append(clause.toString(field));
+ if (i.hasNext()) {
+ buffer.append(", ");
+ }
+ }
+ buffer.append("], ");
+ buffer.append(slop);
+ buffer.append(", ");
+ buffer.append(inOrder);
+ buffer.append(")");
+ buffer.append(ToStringUtils.boost(getBoost()));
+ return buffer.toString();
+ }
+
+ @Override
+ public Spans getSpans(final IndexReader reader) throws IOException {
+ if (clauses.size() == 0) // optimize 0-clause case
+ return new SpanOrQuery(getClauses()).getSpans(reader);
+
+ if (clauses.size() == 1) // optimize 1-clause case
+ return clauses.get(0).getSpans(reader);
+
+ return inOrder
+ ? (Spans) new NearSpansOrdered(this, reader, collectPayloads)
+ : (Spans) new NearSpansUnordered(this, reader);
+ }
+
+ @Override
+ public Query rewrite(IndexReader reader) throws IOException {
+ SpanNearQuery clone = null;
+ for (int i = 0 ; i < clauses.size(); i++) {
+ SpanQuery c = clauses.get(i);
+ SpanQuery query = (SpanQuery) c.rewrite(reader);
+ if (query != c) { // clause rewrote: must clone
+ if (clone == null)
+ clone = (SpanNearQuery) this.clone();
+ clone.clauses.set(i,query);
+ }
+ }
+ if (clone != null) {
+ return clone; // some clauses rewrote
+ } else {
+ return this; // no clauses rewrote
+ }
+ }
+
+ @Override
+ public Object clone() {
+ int sz = clauses.size();
+ SpanQuery[] newClauses = new SpanQuery[sz];
+
+ for (int i = 0; i < sz; i++) {
+ newClauses[i] = (SpanQuery) clauses.get(i).clone();
+ }
+ SpanNearQuery spanNearQuery = new SpanNearQuery(newClauses, slop, inOrder);
+ spanNearQuery.setBoost(getBoost());
+ return spanNearQuery;
+ }
+
+ /** Returns true iff <code>o</code> is equal to this. */
+ @Override
+ public boolean equals(Object o) {
+ if (this == o) return true;
+ if (!(o instanceof SpanNearQuery)) return false;
+
+ final SpanNearQuery spanNearQuery = (SpanNearQuery) o;
+
+ if (inOrder != spanNearQuery.inOrder) return false;
+ if (slop != spanNearQuery.slop) return false;
+ if (!clauses.equals(spanNearQuery.clauses)) return false;
+
+ return getBoost() == spanNearQuery.getBoost();
+ }
+
+ @Override
+ public int hashCode() {
+ int result;
+ result = clauses.hashCode();
+ // Mix bits before folding in things like boost, since it could cancel the
+ // last element of clauses. This particular mix also serves to
+ // differentiate SpanNearQuery hashcodes from others.
+ result ^= (result << 14) | (result >>> 19); // reversible
+ result += Float.floatToRawIntBits(getBoost());
+ result += slop;
+ result ^= (inOrder ? 0x99AFD3BD : 0);
+ return result;
+ }
+}
fnp / pylucene.git / blobdiff