org.jbr.commons.container.java.JavaSpringContainer.java Source code

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Here is the source code for org.jbr.commons.container.java.JavaSpringContainer.java

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/**
 * Copyright (C) - 2013 jbrule
 * 
 * This program 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.
 * 
 * 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 GNU General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>
 */
package org.jbr.commons.container.java;

import org.jbr.commons.container.SpringContainerException;
import org.jbr.commons.container.SpringContainerSupport;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.util.Assert;

/**
 * TODO - type header
 * 
 * @author <a href="mailto:brulejr@gmail.com">Jon Brule</a>
 */
public class JavaSpringContainer extends SpringContainerSupport {

    public final static String JVM_PARM_CONTEXT_CONFIG_CLASS = "JavaSpringContainer.contextConfigClass";
    public final static String JVM_PARM_PROFILE = "app.env";

    private final static String DEFAULT_PROFILE = "LOCAL";

    /**
     * Provides a container-based application with its main entry point.
     * 
     * @param args
     *            the command-line arguments
     */
    public static void main(final String[] args) {
        try {
            final JavaSpringContainer container = new JavaSpringContainer(args);
            container.startup();
        } catch (final SpringContainerException e) {
            e.printStackTrace();
        }
    }

    private Class<?> contextConfigClass;

    /**
     * Constructs a new JavaConfig-based Spring container.
     * 
     * @param contextConfigClass
     *            the context configuration class
     */
    public JavaSpringContainer(final Class<?> contextConfigClass) {
        setContextConfigClass(contextConfigClass);
    }

    /**
     * Constructs a new JavaConfig-based Spring container.
     * 
     * @param args
     *            the command-line arguments
     */
    public JavaSpringContainer(final String[] args) {
    }

    /**
     * Constructs the application context used by this container.
     * 
     * @return this container's new application context
     * @throws SpringContainerException
     */
    @Override
    protected AbstractApplicationContext createApplicationContext() throws SpringContainerException {
        final Class<?> contextConfigClass = getContextConfigClass();
        final String profile = System.getProperty(JVM_PARM_PROFILE, getDefaultProfile());
        log.info("Configuring Java SpringContainer using registered class [" + contextConfigClass
                + "] under profile [" + profile + "]");
        final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
        context.getEnvironment().setActiveProfiles(profile);
        context.register(contextConfigClass);
        context.registerShutdownHook();
        return context;
    }

    /**
     * Obtains the single JavaConfig class used to register when building this
     * container's application context. By default, this looks toward a JVM
     * parameter by the name <code>JavaSpringContainer.contextConfigClass</code>
     * for the configuration classname. This behavior, however, is overriden if
     * the classname is passed as a constructor parameter.
     * 
     * @return the context configuration class
     * @throws SpringContainerException
     *             if unable to find the configuration classname specified by
     *             the JVM parameter
     */
    public Class<?> getContextConfigClass() throws SpringContainerException {
        if (contextConfigClass != null)
            return contextConfigClass;
        else {
            try {
                final String configClassname = System.getProperty(JVM_PARM_CONTEXT_CONFIG_CLASS);
                Assert.notNull(configClassname, "Missing '" + JVM_PARM_CONTEXT_CONFIG_CLASS + "' JVM parameter! "
                        + "Required to bootstrap " + getClass().getSimpleName() + "!");
                return Class.forName(configClassname);
            } catch (final ClassNotFoundException e) {
                throw new SpringContainerException(e.getMessage(), e);
            }
        }
    }

    /**
     * Obtains the default Spring bean profile to activate.
     * 
     * @return the default Spring bean profile
     */
    public String getDefaultProfile() {
        return DEFAULT_PROFILE;
    }

    protected void setContextConfigClass(final Class<?> contextConfigClass) {
        this.contextConfigClass = contextConfigClass;
    }

}