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.text.Collator;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.MultiFields;
import org.apache.lucene.util.ToStringUtils;
/**
* A Query that matches documents within an range of terms.
*
* <p>This query matches the documents looking for terms that fall into the
* supplied range according to {@link
* String#compareTo(String)}, unless a <code>Collator</code> is provided. It is not intended
* for numerical ranges; use {@link NumericRangeQuery} instead.
*
* <p>This query uses the {@link
* MultiTermQuery#CONSTANT_SCORE_AUTO_REWRITE_DEFAULT}
* rewrite method.
* @since 2.9
*/
public class TermRangeQuery extends MultiTermQuery {
private String lowerTerm;
private String upperTerm;
private Collator collator;
private boolean includeLower;
private boolean includeUpper;
/**
* Constructs a query selecting all terms greater/equal than <code>lowerTerm</code>
* but less/equal than <code>upperTerm</code>.
*
* <p>
* If an endpoint is null, it is said
* to be "open". Either or both endpoints may be open. Open endpoints may not
* be exclusive (you can't select all but the first or last term without
* explicitly specifying the term to exclude.)
*
* @param field The field that holds both lower and upper terms.
* @param lowerTerm
* The term text at the lower end of the range
* @param upperTerm
* The term text at the upper end of the range
* @param includeLower
* If true, the <code>lowerTerm</code> is
* included in the range.
* @param includeUpper
* If true, the <code>upperTerm</code> is
* included in the range.
*/
public TermRangeQuery(String field, String lowerTerm, String upperTerm, boolean includeLower, boolean includeUpper) {
this(field, lowerTerm, upperTerm, includeLower, includeUpper, null);
}
/** Constructs a query selecting all terms greater/equal than
* <code>lowerTerm</code> but less/equal than <code>upperTerm</code>.
* <p>
* If an endpoint is null, it is said
* to be "open". Either or both endpoints may be open. Open endpoints may not
* be exclusive (you can't select all but the first or last term without
* explicitly specifying the term to exclude.)
* <p>
* If <code>collator</code> is not null, it will be used to decide whether
* index terms are within the given range, rather than using the Unicode code
* point order in which index terms are stored.
* <p>
* <strong>WARNING:</strong> Using this constructor and supplying a non-null
* value in the <code>collator</code> parameter will cause every single
* index Term in the Field referenced by lowerTerm and/or upperTerm to be
* examined. Depending on the number of index Terms in this Field, the
* operation could be very slow.
*
* @param lowerTerm The Term text at the lower end of the range
* @param upperTerm The Term text at the upper end of the range
* @param includeLower
* If true, the <code>lowerTerm</code> is
* included in the range.
* @param includeUpper
* If true, the <code>upperTerm</code> is
* included in the range.
* @param collator The collator to use to collate index Terms, to determine
* their membership in the range bounded by <code>lowerTerm</code> and
* <code>upperTerm</code>.
*/
public TermRangeQuery(String field, String lowerTerm, String upperTerm, boolean includeLower, boolean includeUpper,
Collator collator) {
super(field);
this.lowerTerm = lowerTerm;
this.upperTerm = upperTerm;
this.includeLower = includeLower;
this.includeUpper = includeUpper;
this.collator = collator;
}
/** Returns the lower value of this range query */
public String getLowerTerm() { return lowerTerm; }
/** Returns the upper value of this range query */
public String getUpperTerm() { return upperTerm; }
/** Returns <code>true</code> if the lower endpoint is inclusive */
public boolean includesLower() { return includeLower; }
/** Returns <code>true</code> if the upper endpoint is inclusive */
public boolean includesUpper() { return includeUpper; }
/** Returns the collator used to determine range inclusion, if any. */
public Collator getCollator() { return collator; }
@Override
protected TermsEnum getTermsEnum(IndexReader reader) throws IOException {
if (collator == null && lowerTerm != null && upperTerm != null && lowerTerm.compareTo(upperTerm) > 0) {
return TermsEnum.EMPTY;
}
if ((lowerTerm == null || (collator == null && includeLower && "".equals(lowerTerm))) && upperTerm == null) {
// NOTE: for now, MultiTermQuery enums terms at the
// MultiReader level, so we must use MultiFields here:
final Terms terms = MultiFields.getTerms(reader, field);
return (terms != null) ? terms.iterator() : null;
}
return new TermRangeTermsEnum(reader, field,
lowerTerm, upperTerm, includeLower, includeUpper, collator);
}
/** @deprecated */
@Deprecated
public String field() {
return getField();
}
/** Prints a user-readable version of this query. */
@Override
public String toString(String field) {
StringBuilder buffer = new StringBuilder();
if (!getField().equals(field)) {
buffer.append(getField());
buffer.append(":");
}
buffer.append(includeLower ? '[' : '{');
buffer.append(lowerTerm != null ? lowerTerm : "*");
buffer.append(" TO ");
buffer.append(upperTerm != null ? upperTerm : "*");
buffer.append(includeUpper ? ']' : '}');
buffer.append(ToStringUtils.boost(getBoost()));
return buffer.toString();
}
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result + ((collator == null) ? 0 : collator.hashCode());
result = prime * result + (includeLower ? 1231 : 1237);
result = prime * result + (includeUpper ? 1231 : 1237);
result = prime * result + ((lowerTerm == null) ? 0 : lowerTerm.hashCode());
result = prime * result + ((upperTerm == null) ? 0 : upperTerm.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!super.equals(obj))
return false;
if (getClass() != obj.getClass())
return false;
TermRangeQuery other = (TermRangeQuery) obj;
if (collator == null) {
if (other.collator != null)
return false;
} else if (!collator.equals(other.collator))
return false;
if (includeLower != other.includeLower)
return false;
if (includeUpper != other.includeUpper)
return false;
if (lowerTerm == null) {
if (other.lowerTerm != null)
return false;
} else if (!lowerTerm.equals(other.lowerTerm))
return false;
if (upperTerm == null) {
if (other.upperTerm != null)
return false;
} else if (!upperTerm.equals(other.upperTerm))
return false;
return true;
}
}