de.dlr.knowledgefinder.dataimport.utils.transformer.ArrayToStringTransformer.java Source code

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Here is the source code for de.dlr.knowledgefinder.dataimport.utils.transformer.ArrayToStringTransformer.java

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/*******************************************************************************
 * Copyright 2016 DLR - German Aerospace Center
 *
 * 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 de.dlr.knowledgefinder.dataimport.utils.transformer;

import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.apache.solr.handler.dataimport.Context;
import org.apache.solr.handler.dataimport.DataImporter;
import org.apache.solr.handler.dataimport.Transformer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * The Class ArrayToStringTransformer. A {@link Transformer} implementation which
 * builds a single string from an string array. Can also work if a single string is given
 * 
 * 
 */
public class ArrayToStringTransformer extends Transformer {

    private static final Logger LOG = LoggerFactory.getLogger(ArrayToStringTransformer.class);

    public static final String ARRAY_SOURCE_DATA_FIELD = "concatArrayFromSource";

    /*
     * @see
     * org.apache.solr.handler.dataimport.Transformer#transformRow(java.util.
     * Map, org.apache.solr.handler.dataimport.Context)
     */
    @Override
    public Object transformRow(Map<String, Object> row, Context context) {

        for (Map<String, String> map : context.getAllEntityFields()) {

            String column = map.get(DataImporter.COLUMN);
            String source = map.get(ARRAY_SOURCE_DATA_FIELD);

            if (source != null && row.containsKey(source) && row.get(source) != null) {
                try {
                    String result = "";
                    if (row.get(source) instanceof Object[]) {
                        Object[] array = (Object[]) row.get(source);
                        result = StringUtils.join(array, ", ");
                    } else
                        result = row.get(source).toString();
                    row.put(column, result);
                } catch (Exception e) {
                    LOG.warn(e.toString());
                }
            }
        }
        return row;
    }

}