import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
@Override
public void start ( final BundleContext context ) throws Exception
{
    this.context = context;
    this.tracker = new ServiceTracker<IProvisioningAgentProvider, IProvisioningAgentProvider> ( context, IProvisioningAgentProvider.class, null );
    this.tracker.open ();
    Activator.INSTANCE = this;
}
 

import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
public static IProvisioningAgent getAgent ( final URI location ) throws ProvisionException
{
    final IProvisioningAgentProvider provider = INSTANCE.tracker.getService ();
    if ( provider == null )
    {
        throw new IllegalStateException ( "Provisioning agent provider not found. Is P2 started?" );
    }

    return provider.createAgent ( location );
}
 

import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
public void start(BundleContext bundleContext) throws Exception {
	provisioningAgentProviderServiceReference= bundleContext.getServiceReference(IProvisioningAgentProvider.SERVICE_NAME);
	if (provisioningAgentProviderServiceReference != null) {
		provisioningAgentProvider= (IProvisioningAgentProvider)bundleContext.getService(provisioningAgentProviderServiceReference);
	}
	plugin= this;
}
 

import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
public boolean shouldUpdate() {
	try {
		IProvisioningAgentProvider agentProvider= Activator.getDefault().getProvisioningAgentProvider();
		if (agentProvider == null) {
			Activator.getDefault().logErrorStatus("Could not find a provisioning agent provider.", new RuntimeException());
			return false;
		}

		final IProvisioningAgent agent= agentProvider.createAgent(null);

		IMetadataRepositoryManager metadataRepositoryManager= (IMetadataRepositoryManager)agent.getService(IMetadataRepositoryManager.SERVICE_NAME);

		if (metadataRepositoryManager == null) {
			Activator.getDefault().logErrorStatus("Could not find the meta data repository manager.", new RuntimeException());
			return false;
		}

		IArtifactRepositoryManager artifactRepositoryManager= (IArtifactRepositoryManager)agent.getService(IArtifactRepositoryManager.SERVICE_NAME);

		if (artifactRepositoryManager == null) {
			Activator.getDefault().logErrorStatus("Could not find the artifact repository manager.", new RuntimeException());
			return false;
		}

		metadataRepositoryManager.addRepository(getUpdateSiteURI(updateSite));
		artifactRepositoryManager.addRepository(getUpdateSiteURI(updateSite));

		metadataRepositoryManager.loadRepository(getUpdateSiteURI(updateSite), new NullProgressMonitor());

		final IProfileRegistry registry= (IProfileRegistry)agent.getService(IProfileRegistry.SERVICE_NAME);

		if (registry == null) {
			Activator.getDefault().logErrorStatus("Could not find the profile registry.", new RuntimeException());
			return false;
		}

		final IProfile profile= registry.getProfile(IProfileRegistry.SELF);

		if (profile == null) {
			Activator.getDefault().logErrorStatus("Could not find the profile.", new RuntimeException());
			return false;
		}

		IQuery<IInstallableUnit> query= QueryUtil.createIUQuery(pluginID);
		Collection<IInstallableUnit> iusToUpdate= profile.query(query, null).toUnmodifiableSet();

		ProvisioningSession provisioningSession= new ProvisioningSession(agent);

		final UpdateOperation updateOperation= new UpdateOperation(provisioningSession, iusToUpdate);

		IStatus modalResolution= updateOperation.resolveModal(new NullProgressMonitor());

		if (modalResolution.isOK())
			return true;
	} catch (ProvisionException e) {
		Activator.getDefault().logErrorStatus("A provisioning exception occured while checking for updates.", e);
	}
	return false;
}
 

import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
public IProvisioningAgentProvider getProvisioningAgentProvider() {
	return provisioningAgentProvider;
}
 

import org.eclipse.equinox.p2.core.IProvisioningAgentProvider; //导入依赖的package包/类
/**
 * Starts the p2 bundles needed to continue with the install.
 * 
 * @param agentLocation Agent location or <code>null</code> to use default agent.
 * @throws ProvisionException on failure to start the agent
 */
private IProvisioningAgent startAgent(IPath agentLocation) throws ProvisionException {
	IProvisioningAgentProvider provider = (IProvisioningAgentProvider) getService(Installer.getDefault().getContext(), IProvisioningAgentProvider.SERVICE_NAME);

	return provider.createAgent(agentLocation == null ? null : agentLocation.toFile().toURI());
}