30. 代码实例-设计模式-回调方式使用模板方法

1）模板类

package com.jd.consume.dao.mysql;

import java.sql.SQLException;
import java.util.Collection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.ibatis.sqlmap.client.SqlMapClient;

/**
 * 批量更新数据
 * @author guanpanpan
 *
 * @param <T>
 */
public abstract class BatchUpdate<T> {
    public final static Logger log = LoggerFactory.getLogger(BatchUpdate.class);
    public static int BANTCH_COMIT_SIZE = 1000;

    public void execute(SqlMapClient db, Collection<T> datas) throws SQLException {
        if (datas == null || datas.size() == 0) {
            return;
        }
        int dealSize = 0;
        try {
            db.startTransaction();
            db.startBatch();
            for (T data : datas) {
                updateToDb(db, data);
                dealSize++;
                if (dealSize >= BANTCH_COMIT_SIZE) {
                    dealSize = 0;
                    db.executeBatch();
                    db.commitTransaction();
                }
            }
            if (dealSize > 0) {
                db.executeBatch();
                db.commitTransaction();
            }

        } catch (SQLException e) {
            log.error("updatedatas To Db error:", e);
            throw e;
        } finally {
            try {
                db.endTransaction();
            } catch (SQLException e) {
                e.printStackTrace();
            }

        }
    }

    public abstract void updateToDb(SqlMapClient db, T data) throws SQLException;
}

（2）使用模板类

new BatchUpdate<ConsumeDetail>() {

@Override

public void updateToDb(SqlMapClient db, ConsumeDetail ConsumeDetail) throws SQLException {

       db.update("ConsumeDetailMysql.insertOrUpdateConsumeDetailWithId", ConsumeDetail);

}

}.execute(dbManager.getSqlMapClientTemplate(dbNo).getSqlMapClient(), ConsumeDetails);

 

注：本示例来源于consume-grade-final(mysql版本)