AseqDecoder.java

/*
 *  Copyright 2015 Lars G. Svensson
 *
 *  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.culturegraph.mf.biblio;

import org.culturegraph.mf.framework.FluxCommand;
import org.culturegraph.mf.framework.StreamReceiver;
import org.culturegraph.mf.framework.annotations.Description;
import org.culturegraph.mf.framework.annotations.In;
import org.culturegraph.mf.framework.annotations.Out;
import org.culturegraph.mf.framework.helpers.DefaultObjectPipe;

/**
 * Parses a raw Aseq stream. UTF-8 encoding expected.
 *
 * @author Lars G. Svensson
 */
@Description("Parses a raw Aseq record (UTF-8 encoding expected).")
@In(String.class)
@Out(StreamReceiver.class)
@FluxCommand("decode-aseq")
public final class AseqDecoder
		extends DefaultObjectPipe<String, StreamReceiver> {

	private static final String FIELD_DELIMITER = "\n";

	@Override
	public void process(final String record) {
		assert !isClosed();
		final String trimedRecord = record.trim();
		if (trimedRecord.isEmpty()) {
			return;
		}
		final String[] lines = trimedRecord.split(FIELD_DELIMITER);
		for (int i = 0; i < lines.length; i++) {
			final String field = lines[i];
			if (i == 0) {
				getReceiver().startRecord(field.substring(0, 9));
			}
			final String category = field.substring(10, 15).trim();
			final String fieldContent = field.substring(18).trim();
			if (!fieldContent.startsWith("$$")) {
				getReceiver().literal(category, fieldContent);
			} else {
				getReceiver().startEntity(category);
				final String[] subfields = fieldContent.split("\\$\\$");
				for (final String subfield : subfields) {
					if (!subfield.isEmpty()) {
						getReceiver().literal(subfield.substring(0, 1), subfield.substring(1));
					}
				}
				getReceiver().endEntity();
			}
		}
		getReceiver().endRecord();
	}

}