/* ========================================================================
* JCommon : a free general purpose class library for the Java(tm) platform
* ========================================================================
*
* (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* -----------------
* PackageState.java
* -----------------
* (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
*
* Original Author: Thomas Morgner;
* Contributor(s): David Gilbert (for Object Refinery Limited);
*
* $Id: PackageState.java,v 1.4 2006/04/14 13:00:56 taqua Exp $
*
* Changes
* -------
* 10-Jul-2003 : Initial version
* 07-Jun-2004 : Added JCommon header (DG);
*
*/
package org.jfree.base.modules;
import org.jfree.util.Log;
/**
* The package state class is used by the package manager to keep track of
* the activation level of the installed or errornous packages.
*
* @author Thomas Morgner
*/
public class PackageState
{
/** A constant defining that the package is new. */
public static final int STATE_NEW = 0;
/** A constant defining that the package has been loaded and configured. */
public static final int STATE_CONFIGURED = 1;
/** A constant defining that the package was initialized and is ready to use. */
public static final int STATE_INITIALIZED = 2;
/** A constant defining that the package produced an error and is not available. */
public static final int STATE_ERROR = -2;
/** The module class that contains the package information. */
private final Module module;
/** The state of the module. */
private int state;
/**
* Creates a new package state for the given module. The module state will
* be initialized to STATE_NEW.
*
* @param module the module.
*/
public PackageState(final Module module)
{
this (module, STATE_NEW);
}
/**
* Creates a new package state for the given module. The module state will
* be initialized to the given initial state.
*
* @param module the module.
* @param state the initial state
*/
public PackageState(final Module module, final int state)
{
if (module == null)
{
throw new NullPointerException("Module must not be null.");
}
if (state != STATE_CONFIGURED && state != STATE_ERROR
&& state != STATE_INITIALIZED && state != STATE_NEW)
{
throw new IllegalArgumentException("State is not valid");
}
this.module = module;
this.state = state;
}
/**
* Configures the module and raises the state to STATE_CONFIGURED if the
* module is not yet configured.
*
* @param subSystem the sub-system.
*
* @return true, if the module was configured, false otherwise.
*/
public boolean configure(final SubSystem subSystem)
{
if (this.state == STATE_NEW)
{
try
{
this.module.configure(subSystem);
this.state = STATE_CONFIGURED;
return true;
}
catch (NoClassDefFoundError noClassDef)
{
Log.warn (new Log.SimpleMessage("Unable to load module classes for ",
this.module.getName(), ":", noClassDef.getMessage()));
this.state = STATE_ERROR;
}
catch (Exception e)
{
if (Log.isDebugEnabled())
{
// its still worth a warning, but now we are more verbose ...
Log.warn("Unable to configure the module " + this.module.getName(), e);
}
else if (Log.isWarningEnabled())
{
Log.warn("Unable to configure the module " + this.module.getName());
}
this.state = STATE_ERROR;
}
}
return false;
}
/**
* Returns the module managed by this state implementation.
*
* @return the module.
*/
public Module getModule()
{
return this.module;
}
/**
* Returns the current state of the module. This method returns either
* STATE_NEW, STATE_CONFIGURED, STATE_INITIALIZED or STATE_ERROR.
*
* @return the module state.
*/
public int getState()
{
return this.state;
}
/**
* Initializes the contained module and raises the set of the module to
* STATE_INITIALIZED, if the module was not yet initialized. In case of an
* error, the module state will be set to STATE_ERROR and the module will
* not be available.
*
* @param subSystem the sub-system.
*
* @return true, if the module was successfully initialized, false otherwise.
*/
public boolean initialize(final SubSystem subSystem)
{
if (this.state == STATE_CONFIGURED)
{
try
{
this.module.initialize(subSystem);
this.state = STATE_INITIALIZED;
return true;
}
catch (NoClassDefFoundError noClassDef)
{
Log.warn (new Log.SimpleMessage("Unable to load module classes for ",
this.module.getName(), ":", noClassDef.getMessage()));
this.state = STATE_ERROR;
}
catch (ModuleInitializeException me)
{
if (Log.isDebugEnabled())
{
// its still worth a warning, but now we are more verbose ...
Log.warn("Unable to initialize the module " + this.module.getName(), me);
}
else if (Log.isWarningEnabled())
{
Log.warn("Unable to initialize the module " + this.module.getName());
}
this.state = STATE_ERROR;
}
catch (Exception e)
{
if (Log.isDebugEnabled())
{
// its still worth a warning, but now we are more verbose ...
Log.warn("Unable to initialize the module " + this.module.getName(), e);
}
else if (Log.isWarningEnabled())
{
Log.warn("Unable to initialize the module " + this.module.getName());
}
this.state = STATE_ERROR;
}
}
return false;
}
/**
* Compares this object with the given other object for equality.
* @see java.lang.Object#equals(java.lang.Object)
*
* @param o the other object to be compared
* @return true, if the other object is also a PackageState containing
* the same module, false otherwise.
*/
public boolean equals(final Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof PackageState))
{
return false;
}
final PackageState packageState = (PackageState) o;
if (!this.module.getModuleClass().equals(packageState.module.getModuleClass()))
{
return false;
}
return true;
}
/**
* Computes a hashcode for this package state.
* @see java.lang.Object#hashCode()
*
* @return the hashcode.
*/
public int hashCode()
{
return this.module.hashCode();
}
}