Metacat

package edu.ucsb.nceas.metacat.index;

import org.dataone.cn.indexer.convert.*;

import org.dataone.cn.indexer.parser.SolrField;

import org.dataone.cn.indexer.solrhttp.SolrElementField;

import org.w3c.dom.Document;

import org.xml.sax.InputSource;

import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.xpath.XPath;

import javax.xml.xpath.XPathExpressionException;

import javax.xml.xpath.XPathFactory;

import java.io.IOException;

import java.io.Reader;

import java.util.List;

/*

 * Wrapper to use DataONE indexer's field-processing code for extraction.

 *

*/

public class D1IndexField extends FieldSpec {

	// man Java enums are awful

	public enum DataFormat { SINGLE, SET, MULTISET }

	public enum Conversion { NONE, DATE, FGDCDATE, LATITUDE, LONGITUDE, FORMAT }

	private static DocumentBuilder docBuilder = null;

	private static final DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

	private static final XPath xpath = XPathFactory.newInstance().newXPath();

	static {

		dbf.setNamespaceAware(true);

		try {

			docBuilder = dbf.newDocumentBuilder();

		} catch (ParserConfigurationException e) {

			e.printStackTrace();

		}

		xpath.setNamespaceContext(new MCXmlNamespace());

	}

	private SolrField d1SolrField;

	public D1IndexField(String name, String xp, DataFormat d, Conversion c) {

		super(name);

		IConverter conv = null;

		switch (c) {

			case NONE: conv = null; break;

			case DATE: conv = new SolrDateConverter(); break;

			case FGDCDATE: conv = new FgdcDateConverter(); break;

			case LATITUDE: conv = new SolrLatitudeConverter(); break;

			case LONGITUDE: conv = new SolrLongitudeConverter(); break;

			case FORMAT: conv = new FormatIdToFormatTypeConverter(); break;

		}

		this.d1SolrField = new SolrField(name, xp, d != DataFormat.SINGLE, conv);

		if (d == DataFormat.SINGLE) {

			this.d1SolrField.setCombineNodes(true);

		}

		else if (d == DataFormat.SET) {

			this.d1SolrField.setDedupe(true);

		}

		this.d1SolrField.initExpression(D1IndexField.xpath);

	}

	@Override

	public String[] extract(final Reader in) {

		List<SolrElementField> fieldList = null;

		try {

			// TODO: encodings

			Document doc = docBuilder.parse(new InputSource(in));

			fieldList = this.solrFields(doc);

		} catch (Exception e) {

			e.printStackTrace();

		}

		if (fieldList != null) {

			String[] fields = new String[fieldList.size()];

			int i = 0;

			for (SolrElementField f : fieldList) {

				fields[i++] = f.getValue();

			}

			return fields;

		} else {

			return new String[0];

		}

	}

	// convenience method for use with DataONE SolrDoc

	public List<SolrElementField> solrFields(final Document doc)

			throws XPathExpressionException, IOException, ParserConfigurationException, SAXException {

		return this.d1SolrField.processField(doc);

	}

}