CdmMessageWriter.java
/* Copyright 2002-2022 CS GROUP
* Licensed to CS GROUP (CS) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* CS 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.orekit.files.ccsds.ndm.cdm;
import java.io.IOException;
import java.time.ZoneOffset;
import java.time.ZonedDateTime;
import org.orekit.files.ccsds.definitions.TimeConverter;
import org.orekit.files.ccsds.section.HeaderKey;
import org.orekit.files.ccsds.section.Segment;
import org.orekit.files.ccsds.section.XmlStructureKey;
import org.orekit.files.ccsds.utils.ContextBinding;
import org.orekit.files.ccsds.utils.FileFormat;
import org.orekit.files.ccsds.utils.generation.Generator;
import org.orekit.files.ccsds.utils.generation.MessageWriter;
import org.orekit.time.AbsoluteDate;
import org.orekit.time.DateComponents;
import org.orekit.time.DateTimeComponents;
import org.orekit.time.TimeComponents;
import org.orekit.time.TimeScale;
/** Cdm message writer.
* @author Melina Vanel
* @since 11.2
*/
public abstract class CdmMessageWriter implements MessageWriter<CdmHeader, CdmSegment, Cdm> {
/** Default value for {@link HeaderKey#ORIGINATOR}. */
public static final String DEFAULT_ORIGINATOR = "OREKIT";
/** Root element for XML files. */
private final String root;
/** Key for format version. */
private final String formatVersionKey;
/** Default format version. */
private final double defaultVersion;
/** Current context binding. */
private ContextBinding context;
/** Current converter for dates. */
private TimeConverter timeConverter;
/** Current format version. */
private double version;
/** Boolean to ensure relative metadata will be written only once. */
private boolean isrelativemetadataWritten;
/**
* Constructor used to create a new NDM writer configured with the necessary parameters
* to successfully fill in all required fields that aren't part of a standard object.
* <p>
* If creation date and originator are not present in header, built-in defaults will be used
* </p>
* @param root root element for XML files
* @param formatVersionKey key for format version
* @param defaultVersion default format version
* @param context context binding (may be reset for each segment)
*/
public CdmMessageWriter(final String root, final String formatVersionKey,
final double defaultVersion, final ContextBinding context) {
this.root = root;
this.defaultVersion = defaultVersion;
this.formatVersionKey = formatVersionKey;
this.version = defaultVersion;
this.isrelativemetadataWritten = false;
setContext(context);
}
/** Reset context binding.
* @param context context binding to use
*/
public void setContext(final ContextBinding context) {
this.context = context;
this.timeConverter = context.getTimeSystem().getConverter(context);
}
/** Get the current context.
* @return current context
*/
public ContextBinding getContext() {
return context;
}
/** Get the current time converter.
* @return current time converter
*/
public TimeConverter getTimeConverter() {
return timeConverter;
}
/** Get the default format version.
* @return default format version
*/
public double getDefaultVersion() {
return defaultVersion;
}
/** {@inheritDoc} */
@Override
public void writeHeader(final Generator generator, final CdmHeader header) throws IOException {
final ZonedDateTime zdt = ZonedDateTime.now(ZoneOffset.UTC);
final TimeScale utc = context.getDataContext().getTimeScales().getUTC();
final AbsoluteDate date = new AbsoluteDate(zdt.getYear(), zdt.getMonthValue(), zdt.getDayOfMonth(),
zdt.getHour(), zdt.getMinute(), zdt.getSecond(),
utc);
// validate before writing
if (header != null) {
if (!Double.isNaN(header.getFormatVersion())) {
// save format version for validating segments
version = header.getFormatVersion();
}
if (header.getCreationDate() == null) {
header.setCreationDate(date);
}
if (header.getOriginator() == null) {
header.setOriginator(DEFAULT_ORIGINATOR);
}
header.validate(version);
}
generator.startMessage(root, formatVersionKey, version);
if (generator.getFormat() == FileFormat.XML) {
generator.enterSection(XmlStructureKey.header.name());
}
// comments are optional
if (header != null) {
generator.writeComments(header.getComments());
}
// creation date is informational only, but mandatory and always in UTC
final DateTimeComponents creationDate = ((header == null) ? date : header.getCreationDate()).getComponents(utc);
final DateComponents dc = creationDate.getDate();
final TimeComponents tc = creationDate.getTime();
generator.writeEntry(HeaderKey.CREATION_DATE.name(),
generator.dateToString(dc.getYear(), dc.getMonth(), dc.getDay(),
tc.getHour(), tc.getMinute(), tc.getSecond()),
null, true);
// Use built-in default if mandatory originator not present
generator.writeEntry(HeaderKey.ORIGINATOR.name(),
header == null ? DEFAULT_ORIGINATOR : header.getOriginator(),
null, true);
if (header != null) {
generator.writeEntry(CdmHeaderKey.MESSAGE_FOR.name(), header.getMessageFor(), null, false);
}
if (header != null) {
generator.writeEntry(HeaderKey.MESSAGE_ID.name(), header.getMessageId(), null, false);
}
if (generator.getFormat() == FileFormat.XML) {
generator.exitSection();
}
// add an empty line for presentation
generator.newLine();
if (generator.getFormat() == FileFormat.XML) {
generator.enterSection(XmlStructureKey.body.name());
}
}
/** {@inheritDoc} */
@Override
public void writeSegment(final Generator generator, final CdmSegment segment) throws IOException {
// validate before writing
segment.getMetadata().validate(version);
segment.getData().validate(version);
// relative metadata should only be written once after the header at the beginning of the body
if (!isrelativemetadataWritten) {
writeRelativeMetadataContent(generator, version, segment.getMetadata().getRelativeMetadata());
isrelativemetadataWritten = true;
}
if (generator.getFormat() == FileFormat.XML) {
generator.enterSection(XmlStructureKey.segment.name());
}
writeSegmentContent(generator, version, segment);
if (generator.getFormat() == FileFormat.XML) {
generator.exitSection();
}
}
/** Write RelativeMetadata part only once after header.
* @param generator generator to use for producing output
* @param formatVersion format version to use
* @param relativeMetadata relative metadata to write
* @throws IOException if any buffer writing operations fails
*/
public abstract void writeRelativeMetadataContent(Generator generator, double formatVersion,
CdmRelativeMetadata relativeMetadata) throws IOException;
/** Write one segment content (without XML wrapping).
* @param generator generator to use for producing output
* @param formatVersion format version to use
* @param segment segment to write
* @throws IOException if any buffer writing operations fails
*/
public abstract void writeSegmentContent(Generator generator, double formatVersion,
Segment<CdmMetadata, CdmData> segment) throws IOException;
/** {@inheritDoc} */
@Override
public void writeFooter(final Generator generator) throws IOException {
if (generator.getFormat() == FileFormat.XML) {
generator.exitSection();
}
generator.endMessage(root);
}
}