org.kuali.common.util.properties.rice.RiceLoader Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of kuali-util Show documentation
Kuali Utilities
There is a newer version: 4.4.17
/**
 * Copyright 2010-2014 The Kuali Foundation
 *
 * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
 *
 * 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.kuali.common.util.properties.rice;

import static org.kuali.common.util.base.Exceptions.illegalState;
import static org.kuali.common.util.base.Precondition.checkNotNull;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.UnmarshallerHandler;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.apache.commons.io.IOUtils;
import org.kuali.common.util.LocationUtils;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

public class RiceLoader {

	public static Properties load(File file) {
		checkNotNull(file, "file");
		return load(file.getAbsolutePath());
	}

	public static Properties load(String location) {
		checkNotNull(location, "location");
		Config config = getConfig(location);
		return convert(config);
	}

	public static Properties load(InputStream in) throws IOException {
		return convert(getConfig(in));
	}

	protected static Properties convert(Config config) {
		checkNotNull(config, "config");
		checkNotNull(config.getParams(), "config.params");
		Properties properties = new Properties();
		for (Param param : config.getParams()) {
			String key = param.getName();
			String val = param.getValue();
			properties.setProperty(key, val);
		}
		return properties;
	}

	protected static Config getConfig(String location) {
		InputStream in = null;
		try {
			in = LocationUtils.getInputStream(location);
			return getConfig(in);
		} catch (IOException e) {
			throw illegalState(e, "unexpected io error -> [%s]", location);
		} finally {
			IOUtils.closeQuietly(in);
		}
	}

	protected static Config getConfig(InputStream in) throws IOException {
		return unmarshal(Config.class, in);
	}

	@SuppressWarnings("unchecked")
	protected static  T unmarshal(Class type, InputStream in) throws IOException {
		try {
			JAXBContext context = JAXBContext.newInstance(type);
			Unmarshaller unmarshaller = context.createUnmarshaller();
			UnmarshallerHandler unmarshallerHandler = unmarshaller.getUnmarshallerHandler();
			SAXParserFactory spf = SAXParserFactory.newInstance();
			SAXParser sp = spf.newSAXParser();
			XMLReader xr = sp.getXMLReader();
			xr.setContentHandler(unmarshallerHandler);
			InputSource xmlSource = new InputSource(in);
			xr.parse(xmlSource);
			return (T) unmarshallerHandler.getResult();
		} catch (SAXException e) {
			throw new IllegalStateException("Unexpected SAX error", e);
		} catch (ParserConfigurationException e) {
			throw new IllegalStateException("Unexpected parser configuration error", e);
		} catch (JAXBException e) {
			throw new IllegalStateException("Unexpected JAXB error", e);
		}
	}

}