org.unidal.web.AbstractContainerServlet Maven / Gradle / Ivy

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package org.unidal.web;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;

import org.codehaus.plexus.DefaultPlexusContainer;
import org.codehaus.plexus.PlexusContainer;
import org.codehaus.plexus.component.repository.exception.ComponentLifecycleException;
import org.codehaus.plexus.component.repository.exception.ComponentLookupException;
import org.codehaus.plexus.logging.Logger;

import org.unidal.lookup.ContainerLoader;
import org.unidal.lookup.LookupException;

public abstract class AbstractContainerServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	private PlexusContainer m_container;

	private Logger m_logger;

	protected PlexusContainer getContainer() {
		return m_container;
	}

	protected Logger getLogger() {
		return m_logger;
	}

	protected  boolean hasComponent(Class role) {
		return hasComponent(role, null);
	}

	protected  boolean hasComponent(Class role, Object roleHint) {
		return m_container.hasComponent(role.getName(), roleHint == null ? "default" : roleHint.toString());
	}

	@Override
	public void init(ServletConfig config) throws ServletException {
		super.init(config);

		try {
			if (m_container == null) {
				m_container = ContainerLoader.getDefaultContainer();
			}

			m_logger = ((DefaultPlexusContainer) m_container).getLoggerManager().getLoggerForComponent(
			      getClass().getName());

			initComponents(config);
		} catch (Exception e) {
			if (m_logger != null) {
				m_logger.error("Servlet initializing failed. " + e, e);
			} else {
				System.out.println("Servlet initializing failed. " + e);
				e.printStackTrace(System.out);
			}

			throw new ServletException("Servlet initializing failed. " + e, e);
		}
	}

	protected abstract void initComponents(ServletConfig config) throws Exception;

	protected  T lookup(Class role) throws LookupException {
		return lookup(role, null);
	}

	protected  T lookup(Class role, String roleHint) throws LookupException {
		try {
			return (T) m_container.lookup(role, roleHint == null ? "default" : roleHint);
		} catch (ComponentLookupException e) {
			throw new LookupException("Component(" + role.getName() + ") lookup failure. details: " + e.getMessage(), e);
		}
	}

	protected void release(Object component) throws LookupException {
		if (component != null) {
			try {
				m_container.release(component);
			} catch (ComponentLifecycleException e) {
				throw new LookupException("Can't release component: " + component, e);
			}
		}
	}

	// For test purpose
	public AbstractContainerServlet setContainer(PlexusContainer container) {
		m_container = container;
		return this;
	}
}