plugins/org.eclipse.mat.ui/src/org/eclipse/mat/ui/snapshot/views/inspector/InspectorContextProvider.java

/*******************************************************************************
 * Copyright (c) 2008, 2021 SAP AG and IBM Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *    SAP AG - initial API and implementation
 *    Andrew Johnson (IBM) - handle missing objects
 *******************************************************************************/
package org.eclipse.mat.ui.snapshot.views.inspector;

import org.eclipse.mat.SnapshotException;
import org.eclipse.mat.query.ContextProvider;
import org.eclipse.mat.query.IContextObject;
import org.eclipse.mat.query.IContextObjectSet;
import org.eclipse.mat.snapshot.ISnapshot;
import org.eclipse.mat.snapshot.OQL;
import org.eclipse.mat.snapshot.model.IClass;
import org.eclipse.mat.ui.snapshot.views.inspector.InspectorView.BaseNode;

/* package */class InspectorContextProvider extends ContextProvider
{
    ISnapshot snapshot;

    public InspectorContextProvider(ISnapshot snapshot)
    {
        super((String) null);
        this.snapshot = snapshot;
    }

    @Override
    public IContextObject getContext(Object row)
    {
        try
        {
            if (row instanceof NamedReferenceNode)
            {
                NamedReferenceNode node = (NamedReferenceNode) row;
                final int objectId = snapshot.mapAddressToId(node.objectAddress);
                return new IContextObject()
                {
                    public int getObjectId()
                    {
                        return objectId;
                    }
                };
            }
            else if (row instanceof BaseNode)
            {
                final BaseNode node = (BaseNode) row;

                if (node.objectId >= 0)
                    return new IContextObject()
                    {
                        public int getObjectId()
                        {
                            return node.objectId;
                        }
                    };
                if (node.addr != Long.MIN_VALUE)
                    return new IContextObjectSet()
                    {

                        @Override
                        public int getObjectId()
                        {
                            return -1;
                        }

                        @Override
                        public int[] getObjectIds()
                        {
                            return new int[0];
                        }

                        @Override
                        public String getOQL()
                        {
                            return OQL.forAddress(node.addr);
                        }
                    };
            }
            else if (row instanceof IClass)
            {
                final IClass clazz = (IClass) row;

                return new IContextObject()
                {
                    public int getObjectId()
                    {
                        return clazz.getObjectId();
                    }
                };
            }
            return null;
        }
        catch (SnapshotException e)
        {
            if (row instanceof NamedReferenceNode)
            {
                NamedReferenceNode node = (NamedReferenceNode) row;
                return new IContextObjectSet() {

                    @Override
                    public int getObjectId()
                    {
                        return -1;
                    }

                    @Override
                    public int[] getObjectIds()
                    {
                        return new int[0];
                    }

                    @Override
                    public String getOQL()
                    {
                        // Used when the address does not convert to an object ID,
                        // such as when objects are discarded.
                        return OQL.forAddress(node.objectAddress);
                    }
                };
            }
            throw new RuntimeException(e);
        }
    }

}