MWTableHandle.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.mappingsmodel.handles;

import org.eclipse.persistence.tools.workbench.mappingsmodel.MWModel;
import org.eclipse.persistence.tools.workbench.mappingsmodel.db.MWTable;
import org.eclipse.persistence.tools.workbench.utility.node.Node;

import org.eclipse.persistence.oxm.XMLDescriptor;

/**
 * MWTableHandle is used to handle a reference to a MWTable
 * via a table name.
 */
public final class MWTableHandle extends MWHandle {

    /**
     * This is the actual table.
     * It is built from the table name, below.
     */
    private volatile MWTable table;

    /**
     * The table name is transient. It is used only to hold its value
     * until postProjectBuild() is called and we can resolve
     * the actual table. We do not keep it in synch with the table
     * itself because we cannot know when the table has been renamed etc.
     */
    private volatile String tableName;


    // ********** constructors **********

    /**
      * default constructor - for TopLink use only
      */
    private MWTableHandle() {
        super();
    }

    public MWTableHandle(MWModel parent, NodeReferenceScrubber scrubber) {
        super(parent, scrubber);
    }

    public MWTableHandle(MWModel parent, MWTable table, NodeReferenceScrubber scrubber) {
        super(parent, scrubber);
        this.table = table;
    }


    // ********** instance methods **********

    public MWTable getTable() {
        return this.table;
    }

    public void setTable(MWTable table) {
        this.table = table;
    }

    protected Node node() {
        return getTable();
    }

    public MWTableHandle setScrubber(NodeReferenceScrubber scrubber) {
        this.setScrubberInternal(scrubber);
        return this;
    }

    public void resolveMetadataHandles() {
        super.resolveMetadataHandles();

        if (this.tableName != null) {
            this.table = this.getDatabase().tableNamed(this.tableName);
        }
        // Ensure tableName is not used by setting it to null....
        this.tableName = null;
    }

    /**
     * Override to delegate comparison to the table itself.
     * If the handles being compared are in a collection that is being sorted,
     * NEITHER table should be null.
     */
    public int compareTo(Object o) {
        return this.table.compareTo(((MWTableHandle) o).table);
    }

    public void toString(StringBuffer sb) {
        if (this.table == null) {
            sb.append("null");
        } else {
            this.table.toString(sb);
        }
    }


    // ********** TopLink methods **********

    public static XMLDescriptor buildDescriptor() {
        XMLDescriptor descriptor = new XMLDescriptor();

        descriptor.setJavaClass(MWTableHandle.class);

        descriptor.addDirectMapping("tableName", "getTableNameForToplink", "setTableNameForToplink", "table-name/text()");

        return descriptor;
    }

    private String getTableNameForToplink() {
        return (this.table == null) ? null : this.table.getName();
    }

    private void setTableNameForToplink(String tableName) {
        this.tableName = tableName;
    }

}