fi.vm.sade.log.client.LoggerJms.java Source code

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Here is the source code for fi.vm.sade.log.client.LoggerJms.java

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/*
 * Copyright (c) 2013 The Finnish Board of Education - Opetushallitus
 *
 * This program is free software:  Licensed under the EUPL, Version 1.1 or - as
 * soon as they will be approved by the European Commission - subsequent versions
 * of the EUPL (the "Licence");
 *
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at: http://www.osor.eu/eupl/
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 */
package fi.vm.sade.log.client;

import org.springframework.jms.core.JmsTemplate;

import fi.vm.sade.log.model.LogEvent;
import fi.vm.sade.log.model.Tapahtuma;
import java.beans.XMLDecoder;
import java.beans.XMLEncoder;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.Session;
import javax.jms.TextMessage;
import org.slf4j.LoggerFactory;
import org.springframework.jms.core.MessageCreator;

public class LoggerJms implements Logger {

    private static final org.slf4j.Logger log = LoggerFactory.getLogger(LoggerJms.class);

    private JmsTemplate jmsTemplate;

    @Override
    public void log(final Tapahtuma tapahtuma) {

        log.debug("log({})", tapahtuma);

        if (jmsTemplate == null) {
            throw new IllegalStateException("LoggerJms - invalid configuration 'jsmTemplate' not available!");
        }

        final LogEvent event = new LogEvent(tapahtuma);

        // Convert message to TextMessage with LogEvent as XML in payload
        jmsTemplate.send(new MessageCreator() {
            @Override
            public Message createMessage(Session session) throws JMSException {
                TextMessage message = session.createTextMessage();
                message.setText(encode(event));
                log.debug("  sending log message - text={}", message.getText());
                return message;
            }
        });

    }

    public void setJmsTemplate(JmsTemplate jmsTemplate) {
        this.jmsTemplate = jmsTemplate;
    }

    /**
     * Encode messages to string (xml).
     *
     * @param event
     * @return
     */
    public static String encode(LogEvent event) {
        if (event == null) {
            return null;
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        XMLEncoder xmlEncoder = new XMLEncoder(baos);
        xmlEncoder.writeObject(event);
        xmlEncoder.close();

        return baos.toString();
    }

    /**
     * Decode XML to LogEvent. Encoded in "encode" method.
     *
     * @param xml
     * @return
     */
    public static LogEvent decode(String xml) {
        if (xml == null) {
            return null;
        }

        ByteArrayInputStream bais = new ByteArrayInputStream(xml.getBytes());
        XMLDecoder xmlDecoder = new XMLDecoder(bais);
        LogEvent logEvent = (LogEvent) xmlDecoder.readObject();
        xmlDecoder.close();

        return logEvent;
    }
}