/*
* 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.
*/
package org.apache.nifi.attribute.expression.language.evaluation.functions;
import java.util.Map;
import java.util.regex.Pattern;
import org.apache.nifi.attribute.expression.language.evaluation.BooleanEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.BooleanQueryResult;
import org.apache.nifi.attribute.expression.language.evaluation.Evaluator;
import org.apache.nifi.attribute.expression.language.evaluation.QueryResult;
import org.apache.nifi.attribute.expression.language.evaluation.literals.StringLiteralEvaluator;
public class FindEvaluator extends BooleanEvaluator {
private final Evaluator<String> subject;
private final Evaluator<String> search;
private final Pattern compiledPattern;
public FindEvaluator(final Evaluator<String> subject, final Evaluator<String> search) {
this.subject = subject;
this.search = search;
// if the search string is a literal, we don't need to evaluate it each time; we can just
// pre-compile it. Otherwise, it must be compiled every time.
if (search instanceof StringLiteralEvaluator) {
this.compiledPattern = Pattern.compile(search.evaluate(null).getValue());
} else {
this.compiledPattern = null;
}
}
@Override
public QueryResult<Boolean> evaluate(final Map<String, String> attributes) {
final String subjectValue = subject.evaluate(attributes).getValue();
if (subjectValue == null) {
return new BooleanQueryResult(false);
}
final Pattern pattern;
if (compiledPattern == null) {
pattern = Pattern.compile(search.evaluate(attributes).getValue());
} else {
pattern = compiledPattern;
}
final boolean found = pattern.matcher(subjectValue).find();
return new BooleanQueryResult(found);
}
@Override
public Evaluator<?> getSubjectEvaluator() {
return subject;
}
}