bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/provisional/p2/ui/model/MetadataRepositoryElement.java

/*******************************************************************************
 * Copyright (c) 2007, 2008 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.equinox.internal.provisional.p2.ui.model;

import java.net.URL;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.equinox.internal.p2.core.helpers.ServiceHelper;
import org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager;
import org.eclipse.equinox.internal.p2.ui.ProvUIActivator;
import org.eclipse.equinox.internal.p2.ui.ProvUIMessages;
import org.eclipse.equinox.internal.p2.ui.model.RemoteQueriedElement;
import org.eclipse.equinox.internal.provisional.p2.core.ProvisionException;
import org.eclipse.equinox.internal.provisional.p2.core.repository.IRepository;
import org.eclipse.equinox.internal.provisional.p2.metadata.repository.IMetadataRepository;
import org.eclipse.equinox.internal.provisional.p2.metadata.repository.IMetadataRepositoryManager;
import org.eclipse.equinox.internal.provisional.p2.query.IQueryable;
import org.eclipse.equinox.internal.provisional.p2.ui.ProvUI;
import org.eclipse.equinox.internal.provisional.p2.ui.ProvUIImages;
import org.eclipse.equinox.internal.provisional.p2.ui.operations.ProvisioningUtil;
import org.eclipse.equinox.internal.provisional.p2.ui.policy.IQueryProvider;
import org.eclipse.osgi.util.NLS;
import org.eclipse.ui.statushandlers.StatusManager;

/**
 * Element wrapper class for a metadata repository that gets its
 * contents in a deferred manner.
 * 
 * @since 3.4
 */
public class MetadataRepositoryElement extends RemoteQueriedElement implements IRepositoryElement {

	URL url;
	boolean isEnabled;
	boolean alreadyReportedNotFound = false;

	public MetadataRepositoryElement(URL url) {
		this(url, true);
	}

	public MetadataRepositoryElement(URL url, boolean isEnabled) {
		this.url = url;
		this.isEnabled = isEnabled;
	}

	public Object getAdapter(Class adapter) {
		if (adapter == IMetadataRepository.class)
			return getQueryable();
		if (adapter == IRepository.class)
			return getQueryable();
		return super.getAdapter(adapter);
	}

	protected String getImageId(Object obj) {
		return ProvUIImages.IMG_METADATA_REPOSITORY;
	}

	protected int getDefaultQueryType() {
		return IQueryProvider.AVAILABLE_IUS;
	}

	public String getLabel(Object o) {
		String name = getName();
		if (name != null && name.length() > 0) {
			return name;
		}
		return getLocation().toExternalForm();
	}

	/*
	 * overridden to lazily fetch repository
	 * (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.query.QueriedElement#getQueryable()
	 */
	public IQueryable getQueryable() {
		if (queryable == null)
			return getMetadataRepository(null);
		return queryable;
	}

	public IRepository getRepository(IProgressMonitor monitor) {
		return getMetadataRepository(monitor);
	}

	private IMetadataRepository getMetadataRepository(IProgressMonitor monitor) {
		if (queryable == null)
			try {
				queryable = ProvisioningUtil.loadMetadataRepository(url, monitor);
			} catch (ProvisionException e) {
				// If repository could not be found, report to the user, but only once.
				// If the user refreshes the repositories, new elements will be created and
				// then a failure would be reported again on the next try.
				if (e.getStatus().getCode() == ProvisionException.REPOSITORY_NOT_FOUND) {
					if (!alreadyReportedNotFound) {
						// report the status, not the exception, to the user because we
						// do not want to show them stack trace and exception detail.
						ProvUI.reportNotFoundStatus(url, e.getStatus(), StatusManager.SHOW);
						alreadyReportedNotFound = true;
					}
				} else
					// handle other exceptions the normal way
					handleException(e, NLS.bind(ProvUIMessages.MetadataRepositoryElement_RepositoryLoadError, url));
			}
		return (IMetadataRepository) queryable;

	}

	/*
	 * overridden to check whether url is specified rather
	 * than loading the repo via getQueryable()
	 * (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.query.QueriedElement#knowsQueryable()
	 */
	public boolean knowsQueryable() {
		return url != null;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.model.RepositoryElement#getURL()
	 */
	public URL getLocation() {
		return url;
	}

	/*
	 * (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.model.RepositoryElement#getName()
	 */
	public String getName() {
		try {
			String name = ProvisioningUtil.getMetadataRepositoryProperty(url, IRepository.PROP_NAME);
			if (name == null)
				return ""; //$NON-NLS-1$
			return name;
		} catch (ProvisionException e) {
			return ""; //$NON-NLS-1$
		}
	}

	/*
	 * (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.model.RepositoryElement#getDescription()
	 */
	public String getDescription() {
		if (alreadyReportedNotFound)
			return ProvUIMessages.MetadataRepositoryElement_NotFound;
		try {
			String description = ProvisioningUtil.getMetadataRepositoryProperty(url, IRepository.PROP_DESCRIPTION);
			if (description == null)
				return ""; //$NON-NLS-1$
			return description;
		} catch (ProvisionException e) {
			return ""; //$NON-NLS-1$
		}
	}

	/* (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.model.RepositoryElement#isEnabled()
	 */
	public boolean isEnabled() {
		return isEnabled;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.model.IRepositoryElement#setEnabled(boolean)
	 */
	public void setEnabled(boolean enabled) {
		isEnabled = enabled;
	}

	/*
	 * Overridden to check whether a repository instance has already been loaded.
	 * This is necessary to prevent background loading of an already loaded repository
	 * by the DeferredTreeContentManager, which will add redundant children to the
	 * viewer.  
	 * see https://bugs.eclipse.org/bugs/show_bug.cgi?id=229069
	 * see https://bugs.eclipse.org/bugs/show_bug.cgi?id=226343
	 * (non-Javadoc)
	 * @see org.eclipse.equinox.internal.provisional.p2.ui.query.QueriedElement#hasQueryable()
	 */
	public boolean hasQueryable() {
		if (queryable != null)
			return true;
		if (url == null)
			return false;
		IMetadataRepositoryManager manager = (IMetadataRepositoryManager) ServiceHelper.getService(ProvUIActivator.getContext(), IMetadataRepositoryManager.class.getName());
		if (manager == null || !(manager instanceof MetadataRepositoryManager))
			return false;
		IMetadataRepository repo = ((MetadataRepositoryManager) manager).getRepository(url);
		if (repo == null)
			return false;
		queryable = repo;
		return true;
	}
}