/*
* Copyright 2015-2016 the original author or authors.
*
* Licensed 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.
*/
package org.springframework.data.mongodb.core.query;
import java.util.regex.Pattern;
import org.springframework.data.repository.query.parser.Part.Type;
import org.springframework.util.ObjectUtils;
/**
* @author Christoph Strobl
* @author Mark Paluch
* @since 1.8
*/
public enum MongoRegexCreator {
INSTANCE;
private static final Pattern PUNCTATION_PATTERN = Pattern.compile("\\p{Punct}");
/**
* Creates a regular expression String to be used with {@code $regex}.
*
* @param source the plain String
* @param type
* @return {@literal source} when {@literal source} or {@literal type} is {@literal null}.
*/
public String toRegularExpression(String source, Type type) {
if (type == null || source == null) {
return source;
}
String regex = prepareAndEscapeStringBeforeApplyingLikeRegex(source, type);
switch (type) {
case STARTING_WITH:
regex = "^" + regex;
break;
case ENDING_WITH:
regex = regex + "$";
break;
case CONTAINING:
case NOT_CONTAINING:
regex = ".*" + regex + ".*";
break;
case SIMPLE_PROPERTY:
case NEGATING_SIMPLE_PROPERTY:
regex = "^" + regex + "$";
default:
}
return regex;
}
private String prepareAndEscapeStringBeforeApplyingLikeRegex(String source, Type type) {
if (ObjectUtils.nullSafeEquals(Type.REGEX, type)) {
return source;
}
if (!ObjectUtils.nullSafeEquals(Type.LIKE, type) && !ObjectUtils.nullSafeEquals(Type.NOT_LIKE, type)) {
return PUNCTATION_PATTERN.matcher(source).find() ? Pattern.quote(source) : source;
}
if (source.equals("*")) {
return ".*";
}
StringBuilder sb = new StringBuilder();
boolean leadingWildcard = source.startsWith("*");
boolean trailingWildcard = source.endsWith("*");
String valueToUse = source.substring(leadingWildcard ? 1 : 0,
trailingWildcard ? source.length() - 1 : source.length());
if (PUNCTATION_PATTERN.matcher(valueToUse).find()) {
valueToUse = Pattern.quote(valueToUse);
}
if (leadingWildcard) {
sb.append(".*");
}
sb.append(valueToUse);
if (trailingWildcard) {
sb.append(".*");
}
return sb.toString();
}
}