com.glaf.core.id.MyBatisDbIdGenerator.java Source code

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Here is the source code for com.glaf.core.id.MyBatisDbIdGenerator.java

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/* 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 com.glaf.core.id;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import com.glaf.core.dao.EntityDAO;

@Service("idGenerator")
@Transactional
public class MyBatisDbIdGenerator implements IdGenerator {
    protected final static Log logger = LogFactory.getLog(MyBatisDbIdGenerator.class);

    protected volatile EntityDAO entityDAO;

    protected volatile long lastId = -1;

    protected volatile long nextId = 0;

    public MyBatisDbIdGenerator() {
        logger.info("----------------MyBatis3DbIdGenerator--------------");
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW)
    protected synchronized void getNewBlock() {
        IdBlock idBlock = entityDAO.nextDbidBlock();
        this.nextId = idBlock.getNextId();
        this.lastId = idBlock.getLastId();
        if (logger.isDebugEnabled()) {
            logger.debug("----------------NEXTID------------------------");
            logger.debug("nextId:" + nextId);
            logger.debug("lastId:" + lastId);
        }
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public synchronized String getNextId() {
        return Long.toString(this.nextId());
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public synchronized String getNextId(String name) {
        return Long.toString(this.nextId(name));
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public synchronized Long nextId() {
        if (lastId < nextId) {
            getNewBlock();
        }
        return nextId++;
    }

    @Transactional
    public synchronized Long nextId(String name) {
        IdBlock idBlock = entityDAO.nextDbidBlock(name);
        return idBlock.getNextId();
    }

    @Transactional
    public synchronized Long nextId(String tablename, String idColumn) {
        long maxId = entityDAO.getMaxId(tablename, idColumn);
        return maxId + 1;
    }

    public synchronized void setEntityDAO(EntityDAO entityDAO) {
        this.entityDAO = entityDAO;
    }
}