/*
* 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 gobblin.converter.string;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import com.google.common.base.Optional;
import com.google.common.base.Strings;
import gobblin.configuration.ConfigurationKeys;
import gobblin.configuration.WorkUnitState;
import gobblin.converter.Converter;
import gobblin.converter.DataConversionException;
import gobblin.converter.EmptyIterable;
import gobblin.converter.SchemaConversionException;
import gobblin.converter.SingleRecordIterable;
import gobblin.util.ForkOperatorUtils;
/**
* Implementation of {@link Converter} which filters strings based on whether or not they match a regex specified by
* {@link ConfigurationKeys#CONVERTER_STRING_FILTER_PATTERN}
*/
public class StringFilterConverter extends Converter<Class<String>, Class<String>, String, String> {
private Pattern pattern;
private Optional<Matcher> matcher;
@Override
public Converter<Class<String>, Class<String>, String, String> init(WorkUnitState workUnit) {
this.pattern = Pattern.compile(Strings.nullToEmpty(workUnit.getProp(
ForkOperatorUtils.getPropertyNameForBranch(workUnit, ConfigurationKeys.CONVERTER_STRING_FILTER_PATTERN))));
this.matcher = Optional.absent();
return this;
}
@Override
public Class<String> convertSchema(Class<String> inputSchema, WorkUnitState workUnit)
throws SchemaConversionException {
return inputSchema;
}
@Override
public Iterable<String> convertRecord(Class<String> outputSchema, String inputRecord, WorkUnitState workUnit)
throws DataConversionException {
if (!this.matcher.isPresent()) {
this.matcher = Optional.of(this.pattern.matcher(inputRecord));
} else {
this.matcher.get().reset(inputRecord);
}
return this.matcher.get().matches() ? new SingleRecordIterable<>(inputRecord) : new EmptyIterable<String>();
}
}