SuperCsvRenderer.java

/**
 * Copyright (c) 2013-2016, The SeedStack authors <http://seedstack.org>
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
package org.seedstack.io.supercsv.internal;

import org.apache.commons.lang.StringUtils;
import org.seedstack.io.spi.AbstractTemplateRenderer;
import org.seedstack.io.supercsv.SuperCsvTemplate;
import org.seedstack.seed.SeedException;
import org.supercsv.cellprocessor.ift.CellProcessor;
import org.supercsv.io.CsvBeanWriter;
import org.supercsv.io.ICsvBeanWriter;

import javax.inject.Named;
import java.io.Closeable;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

@Named("SuperCSV")
class SuperCsvRenderer extends AbstractTemplateRenderer<SuperCsvTemplate> {
    private static final String SUPPORTED_MIME_TYPE = "application/csv";
    private static final String TEMPLATE = "template";

    @Override
    public void render(OutputStream outputStream, Object model) {
        render(outputStream, model, null, null);
    }

    @Override
    public void render(OutputStream outputStream, Object model, String mimeType, Map<String, Object> parameters) {
        if (mimeType != null && !StringUtils.equals(mimeType, SUPPORTED_MIME_TYPE)) {
            throw new IllegalArgumentException(mimeType
                    + " not supported. SuperCsvRenderer only supports application/csv MIME type");
        }

        ICsvBeanWriter beanWriter = null;
        try {
            beanWriter = new CsvBeanWriter(new OutputStreamWriter(outputStream, template.getCharsetName()),
                    template.getPreferences());

            final List<CellProcessor> confList = template.getWritingCellProcessors();
            final CellProcessor[] processors = confList.toArray(new CellProcessor[confList.size()]);
            final String[] fields = template.getFields().toArray(new String[template.getFields().size()]);

            // write the header
            if (template.showHeader()) {
                beanWriter.writeHeader(template.getHeaders().toArray(new String[template.getHeaders().size()]));
            }

            // If model is a collection, iterates over the collection
            if (model instanceof Collection) {
                Collection<?> col = (Collection<?>) model;
                Iterator<?> it = col.iterator();
                while (it.hasNext()) {
                    beanWriter.write(it.next(), fields, processors);
                }
            } else {
                // else write the pojo
                beanWriter.write(model, fields, processors);
            }
            //
            // Catch all possible fails when rendering super csv export.
            //
        } catch (Exception e) {
            throw SeedException.wrap(e, SuperCsvErrorCode.ERROR_DURING_SUPER_CSV_RENDERING)
                    .put(TEMPLATE, template.getName());
        } finally {
            closeQuietly(beanWriter);
        }
    }

    private void closeQuietly(Closeable closeable) {
        try {
            if (closeable != null) {
                closeable.close();
            }
        } catch (IOException e) {
            // ignore
        }
    }
}