bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/registry/ViewDescriptor.java

/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ui.internal.registry;

import java.util.StringTokenizer;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;

import org.eclipse.jface.resource.ImageDescriptor;

import org.eclipse.ui.IPageLayout;
import org.eclipse.ui.IPluginContribution;
import org.eclipse.ui.IViewPart;
import org.eclipse.ui.internal.WorkbenchPlugin;
import org.eclipse.ui.plugin.AbstractUIPlugin;

/**
 * Capture the attributes of a view extension.
 */
public class ViewDescriptor implements IViewDescriptor, IPluginContribution {
	private String id;
	private String pluginId;
	private ImageDescriptor imageDescriptor;
	private static final String ATT_ID = "id"; //$NON-NLS-1$
	private static final String ATT_NAME = "name"; //$NON-NLS-1$
	private static final String ATT_ACCELERATOR = "accelerator"; //$NON-NLS-1$
	private static final String ATT_ICON = "icon"; //$NON-NLS-1$
	private static final String ATT_CATEGORY = "category"; //$NON-NLS-1$
	private static final String ATT_CLASS = "class"; //$NON-NLS-1$
	private static final String ATT_RATIO = "fastViewWidthRatio"; //$NON-NLS-1$
	private static final String ATT_MULTIPLE = "allowMultiple"; //$NON-NLS-1$
	private String label;
	private String accelerator;
	private String className;
	private IConfigurationElement configElement;
	private String[] categoryPath;
	private String description;
	private float fastViewWidthRatio;
	private boolean allowMultiple;
    
	/**
	 * Create a new ViewDescriptor for an extension.
	 */
	public ViewDescriptor(IConfigurationElement e, String desc)
		throws CoreException {
		configElement = e;
		description = desc;
		loadFromExtension();
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#createView()
	 */
	public IViewPart createView() throws CoreException {
		Object obj = WorkbenchPlugin.createExtension(configElement, ATT_CLASS);
		return (IViewPart) obj;
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getCategoryPath()
	 */
	public String[] getCategoryPath() {
		return categoryPath;
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getConfigurationElement()
	 */
	public IConfigurationElement getConfigurationElement() {
		return configElement;
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getDescription()
	 */
	public String getDescription() {
		return description;
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getID()
	 */
	public String getID() {
		return id;
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkbenchPartDescriptor#getId()
	 */
	public String getId() {
		return id;
	}
    
	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkbenchPartDescriptor#getImageDescriptor()
	 */
	public ImageDescriptor getImageDescriptor() {
		if (imageDescriptor != null)
			return imageDescriptor;
		String iconName = configElement.getAttribute(ATT_ICON);
		if (iconName == null)
			return null;
		IExtension extension = configElement.getDeclaringExtension();
		String extendingPluginId =
			extension.getDeclaringPluginDescriptor().getUniqueIdentifier();
		imageDescriptor =
			AbstractUIPlugin.imageDescriptorFromPlugin(
				extendingPluginId,
				iconName);
		return imageDescriptor;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkbenchPartDescriptor#getLabel()
	 */
	public String getLabel() {
		return label;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getAccelerator()
	 */
	public String getAccelerator() {
		return accelerator;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.internal.registry.IViewDescriptor#getFastViewWidthRatio()
	 */
	public float getFastViewWidthRatio() {
		return fastViewWidthRatio;
	}

	/**
	 * load a view descriptor from the registry.
	 */
	private void loadFromExtension() throws CoreException {
		id = configElement.getAttribute(ATT_ID);
		pluginId =
			configElement
				.getDeclaringExtension()
				.getDeclaringPluginDescriptor()
				.getUniqueIdentifier();
		label = configElement.getAttribute(ATT_NAME);
		accelerator = configElement.getAttribute(ATT_ACCELERATOR);
		className = configElement.getAttribute(ATT_CLASS);
		String category = configElement.getAttribute(ATT_CATEGORY);
		String ratio = configElement.getAttribute(ATT_RATIO);
		String mult = configElement.getAttribute(ATT_MULTIPLE);
		
		// Sanity check.
		if ((label == null) || (className == null)) {
			throw new CoreException(new Status(IStatus.ERROR, configElement.getDeclaringExtension().getDeclaringPluginDescriptor().getUniqueIdentifier(), 0, "Invalid extension (missing label or class name): " + id, //$NON-NLS-1$
			null));
		}
		if (category != null) {
			StringTokenizer stok = new StringTokenizer(category, "/"); //$NON-NLS-1$
			categoryPath = new String[stok.countTokens()];
			// Parse the path tokens and store them
			for (int i = 0; stok.hasMoreTokens(); i++) {
				categoryPath[i] = stok.nextToken();
			}
		}

		if (ratio != null) {
			try {
				fastViewWidthRatio = new Float(ratio).floatValue();
				if (fastViewWidthRatio > IPageLayout.RATIO_MAX)
					fastViewWidthRatio = IPageLayout.RATIO_MAX;
				if (fastViewWidthRatio < IPageLayout.RATIO_MIN)
					fastViewWidthRatio = IPageLayout.RATIO_MIN;
			} catch (NumberFormatException e) {
				fastViewWidthRatio = IPageLayout.DEFAULT_FASTVIEW_RATIO;
			}
		} else {
			fastViewWidthRatio = IPageLayout.DEFAULT_FASTVIEW_RATIO;
		}
		allowMultiple = mult != null && "true".equalsIgnoreCase(mult); //$NON-NLS-1$
	}
	/**
	 * Returns a string representation of this descriptor. For debugging
	 * purposes only.
	 */
	public String toString() {
		return "View(" + getID() + ")"; //$NON-NLS-2$//$NON-NLS-1$
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.activities.support.IPluginContribution#getPluginId()
	 */
	public String getPluginId() {
		return pluginId == null ? "" : pluginId; //$NON-NLS-1$    
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.activities.support.IPluginContribution#getLocalId()
	 */
	public String getLocalId() {
		return id == null ? "" : id; //$NON-NLS-1$	
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.activities.support.IPluginContribution#fromPlugin()
	 */
	public boolean fromPlugin() {
		return true;
	}

    /* (non-Javadoc)
     * @see org.eclipse.ui.internal.registry.IViewDescriptor#getAllowMultiple()
     */
    public boolean getAllowMultiple() {
        return allowMultiple;
    }
}