/**
* 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.camel.dataformat.csv;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.camel.Exchange;
import org.apache.camel.spi.DataFormat;
import org.apache.camel.util.ExchangeHelper;
import org.apache.camel.util.ObjectHelper;
import org.apache.commons.csv.CSVParser;
import org.apache.commons.csv.CSVStrategy;
import org.apache.commons.csv.writer.CSVConfig;
import org.apache.commons.csv.writer.CSVField;
import org.apache.commons.csv.writer.CSVWriter;
/**
* CSV Data format.
* <p/>
* By default, columns are autogenerated in the resulting CSV. Subsequent
* messages use the previously created columns with new fields being added at
* the end of the line. Thus, field order is the same from message to message.
* Autogeneration can be disabled. In this case, only the fields defined in
* csvConfig are written on the output.
*
* @version $Revision: 814293 $
*/
public class CsvDataFormat implements DataFormat {
private CSVStrategy strategy = CSVStrategy.DEFAULT_STRATEGY;
private CSVConfig config = new CSVConfig();
private boolean autogenColumns = true;
public void marshal(Exchange exchange, Object object, OutputStream outputStream) throws Exception {
ObjectHelper.notNull(config, "config");
OutputStreamWriter out = new OutputStreamWriter(outputStream);
CSVWriter csv = new CSVWriter(config);
csv.setWriter(out);
try {
List list = ExchangeHelper.convertToType(exchange, List.class, object);
if (list != null) {
for (Object child : list) {
Map row = ExchangeHelper.convertToMandatoryType(exchange, Map.class, child);
doMarshalRecord(exchange, row, out, csv);
}
} else {
Map row = ExchangeHelper.convertToMandatoryType(exchange, Map.class, object);
doMarshalRecord(exchange, row, out, csv);
}
} finally {
out.close();
}
}
private void doMarshalRecord(Exchange exchange, Map row, Writer out, CSVWriter csv) throws Exception {
if (autogenColumns) {
// no specific config has been set so lets add fields
Set set = row.keySet();
updateFieldsInConfig(set, exchange);
}
csv.writeRecord(row);
}
public Object unmarshal(Exchange exchange, InputStream inputStream) throws Exception {
InputStreamReader in = new InputStreamReader(inputStream);
try {
CSVParser parser = new CSVParser(in, getStrategy());
List<List<String>> list = new ArrayList<List<String>>();
while (true) {
String[] strings = parser.getLine();
if (strings == null) {
break;
}
List<String> line = Arrays.asList(strings);
list.add(line);
}
if (list.size() == 1) {
return list.get(0);
} else {
return list;
}
} finally {
in.close();
}
}
public void setConfig(CSVConfig config) {
this.config = config;
}
public CSVStrategy getStrategy() {
return strategy;
}
public void setStrategy(CSVStrategy strategy) {
this.strategy = strategy;
}
public boolean isAutogenColumns() {
return autogenColumns;
}
/**
* Auto generate columns.
*
* @param autogenColumns set to false to disallow column autogeneration (default true)
*/
public void setAutogenColumns(boolean autogenColumns) {
this.autogenColumns = autogenColumns;
}
protected CSVConfig createConfig() {
return new CSVConfig();
}
private synchronized void updateFieldsInConfig(Set set, Exchange exchange) {
for (Object value : set) {
if (value != null) {
String text = exchange.getContext().getTypeConverter().convertTo(String.class, value);
// do not add field twice
if (config.getField(text) == null) {
CSVField field = new CSVField(text);
config.addField(field);
}
}
}
}
}