GraphConfigGenerator.java

/**
 * *****************************************************************************
 * This file is part of OpenNMS(R).
 *
 * Copyright (C) 2007-2011 The OpenNMS Group, Inc. OpenNMS(R) is Copyright (C)
 * 1999-2011 The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * OpenNMS(R) 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 GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * OpenNMS(R). If not, see: http://www.gnu.org/licenses/
 *
 * For more information contact: OpenNMS(R) Licensing <license@opennms.org>
 * http://www.opennms.org/ http://www.opennms.com/
 * *****************************************************************************
 */
package org.opennms.tools.jmxconfiggenerator.graphs;

import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
import java.util.Collection;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.app.VelocityEngine;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.RuntimeConstants;
import org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Simon Walter <simon.walter@hp-factory.de>
 * @author Markus Neumann <markus@opennms.com>
 */
public class GraphConfigGenerator {

    private static Logger logger = LoggerFactory.getLogger(GraphConfigGenerator.class);

    public String generateSnmpGraph(Collection<Report> reports, String graphTemplate) {
        Velocity.init();
        VelocityContext context = new VelocityContext();

        context.put("reportsList", reports.iterator());
        context.put("reportsBody", reports.iterator());
        Template template = null;

        try {
            template = Velocity.getTemplate(graphTemplate);
        } catch (ResourceNotFoundException rnfe) {
            logger.debug("couldn't find the template:'{}'", rnfe.getMessage());
        } catch (ParseErrorException pee) {
            logger.debug("syntax error: problem parsing the template:'{}'", pee.getMessage());
        } catch (MethodInvocationException mie) {
            logger.debug("something invoked in the template threw an exception:'{}'", mie.getMessage());
        } catch (Exception e) {
            logger.debug("undefined exception:'{}'", e.getMessage());
        }

        StringWriter sw = new StringWriter();

        if (template != null) {
            template.merge(context, sw);
        }

        return sw.toString();
    }

    public String generateSnmpGraph(Collection<Report> reports) throws IOException, Exception {
        String jarInternTemplate = "graphTemplate.vm";

        VelocityEngine velocityEngine = new VelocityEngine();
        velocityEngine.setProperty(RuntimeConstants.RESOURCE_LOADER, "classpath");
        velocityEngine.setProperty("classpath.resource.loader.class", ClasspathResourceLoader.class.getName());

        velocityEngine.init();

        final String templatePath = jarInternTemplate;
        InputStream input = this.getClass().getClassLoader().getResourceAsStream(templatePath);
        if (input == null) {
            throw new IOException("Template file doesn't exist " + jarInternTemplate);
        }

        VelocityContext context = new VelocityContext();

        context.put("reportsList", reports.iterator());
        context.put("reportsBody", reports.iterator());

        Template template = null;

        try {
            template = velocityEngine.getTemplate(templatePath, "UTF-8");
        } catch (ResourceNotFoundException rnfe) {
            logger.debug("couldn't find the template:'{}'", rnfe.getMessage());
        } catch (ParseErrorException pee) {
            logger.debug("syntax error: problem parsing the template:'{}'", pee.getMessage());
        } catch (MethodInvocationException mie) {
            logger.debug("something invoked in the template threw an exception:'{}'", mie.getMessage());
        } catch (Exception e) {
            logger.debug("undefined exception:'{}'", e.getMessage());
        }

        StringWriter sw = new StringWriter();

        if (template != null) {
            template.merge(context, sw);
        }

        return sw.toString();
    }
}