corner.services.tree.MoveDownProcessor.java Source code

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Here is the source code for corner.services.tree.MoveDownProcessor.java

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/* 
 * Copyright 2008 The Corner Team.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package corner.services.tree;

import java.util.List;

import org.hibernate.Criteria;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Restrictions;
import org.springframework.beans.BeanInstantiationException;
import org.springframework.beans.BeanUtils;

import corner.entities.base.TreeAdapter;

/**
 * ???
 * 
 * @author <a href="mailto:jun.tsai@ganshane.net">Jun Tsai</a>
 * @version $Revision: 2956 $
 * @since 0.0.1 
 */
class MoveDownProcessor extends AbstractMoveTreeNodeProcessor implements MoveTreeNodeProcessor {

    private int moveBlockLeftStart = 0;

    private int moveBlockLeftEnd = Integer.MAX_VALUE;

    private int offset = 0;

    @Override
    protected void appendQueryReplaceNodeCriteria(Criteria criteria) {
        criteria.add(Restrictions.gt(TreeAdapter.RIGHT_PRO_NAME, getCurrentNode().getRight()))
                .add(Restrictions.lt(TreeAdapter.RIGHT_PRO_NAME, getParentNode().getRight()));
        criteria.addOrder(Order.asc(TreeAdapter.LEFT_PRO_NAME));

    }

    @Override
    protected void fetchMoveBlockInfo(List<? extends TreeAdapter> list) {
        if (list.size() == 0) { // ??
            offset = (getParentNode().getRight() - 1) - getCurrentNode().getRight();
            moveBlockLeftStart = getCurrentNode().getRight() + 1;
            moveBlockLeftEnd = getParentNode().getRight();
        } else {// ?
            TreeAdapter replaceNode = list.get(0);
            offset = replaceNode.getRight() - getCurrentNode().getRight();
            moveBlockLeftStart = getCurrentNode().getRight() + 1;
            moveBlockLeftEnd = replaceNode.getRight();
        }

    }

    @Override
    protected int getMoveBlockLeftEnd() {
        return this.moveBlockLeftEnd;
    }

    @Override
    protected int getMoveBlockLeftStart() {
        return this.moveBlockLeftStart;
    }

    @Override
    protected int getOffset() {
        return this.offset;
    }

    @Override
    protected int getUpdateWidth() {
        return getCurrentNode().getLeft() - getCurrentNode().getRight() - 1;
    }

    @Override
    protected TreeAdapter constructRootNode() {
        TreeAdapter rootNode;
        try {
            rootNode = (TreeAdapter) BeanUtils.instantiateClass(Class.forName(getTreeClassName()));
        } catch (BeanInstantiationException e) {
            throw new RuntimeException(e);
        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        }
        rootNode.setLeft(0);

        long rowCount = (Long) getEntityService().find("select count(*) from " + getTreeClassName()).next();
        rootNode.setRight((int) (rowCount * 2 + 1));

        return rootNode;
    }
}