"iBATIS"的簡易實現

java 代碼

package com.viwo.sqlmap.config;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.digester.Digester;

import org.apache.log4j.Logger;


import com.viwo.sqlmap.factory.ConnectionFactory;

/**
 * DAO using this class, don't need write jdbc operations.
 *
 * @author viwo
 *
 */
public class SqlMapConfig
{
 private final static Logger logger = Logger.getLogger(SqlMapConfig.class);
 private Map selectMap = new HashMap();
 private Map executeMap = new HashMap();
 private static Map configMap = new HashMap();
 private Connection connection = null;
 private Statement statement = null;
    /**
     * get a List object from database
     *
     * fit for this sql: select username,password from users
     *
     * the " name, password " and its values are packed in an object list of return
     * list.
     *
     * @param selectId
     * @param paramObject
     * @return List
     * @throws Exception
     */
 public List QueryForList(String selectId,Object paramObject) throws Exception
 {
  logger.debug("[viwo]-->[enter QueryForList]");
  List list = new ArrayList();

  try
  {
   ConfigSelect configSelect =(ConfigSelect)selectMap.get(selectId);
   if(configSelect!=null)
   {
    String sql = configSelect.getSql();
    String type = configSelect.getType();
    String param = configSelect.getParam();
          if(paramObject.getClass() != Class.forName(param))
          {
           return null;
          }
          String[] sqls = sql.split("#");
          if(sqls.length>1)
          {
           for(int i=0;i            {
            if(i%2!=0)
            {
             String tmpValue = BeanUtils.getProperty(paramObject, sqls[i]);
             sql = sql.replaceFirst("#"+sqls[i]+"#", "'"+tmpValue+"'");
            }
           }
          }
          logger.debug("[viwo]-->[QueryForList]-->[sql:]"+sql);
    //PreparedStatement ps = connection.prepareStatement(sql);
    ResultSet rs = statement.executeQuery(sql);
    ResultSetMetaData meta =  rs.getMetaData();
       int columnCount = meta.getColumnCount();
       while(rs.next())
       {
        Object newItem = Class.forName(type).newInstance();
        for(int i=1;i<=columnCount;i++)
        {
         Object rsItem = null;
         String columnType = meta.getColumnTypeName(i);
         if(columnType.equals("numeric"))
          rsItem = new Double(rs.getDouble(meta.getColumnName(i)));
         else if(columnType.equals("int"))
          rsItem = new Integer(rs.getInt(meta.getColumnName(i)));
         else
          rsItem = rs.getString(meta.getColumnName(i));

         BeanUtils.setProperty(newItem, meta.getColumnName(i), rsItem);
        }
        list.add(newItem);
       }
   }

  }
  catch (Exception e)
  {
   logger.error("[viwo]-->[QueryForList]-->"+e.getMessage());
   throw new Exception(e);
  }
  return list;
 }

    /**
     * get an object from database
     *
     * fit for this sql: select username,password from users where username=#username#
     *
     * the " name, password " and its values are packed in an object of return
     * object.
     *
     * @param selectId
     * @param paramObject
     * @return Object
     * @throws Exception
     */
 public Object QueryForObject(String selectId,Object paramObject) throws Exception
 {
  logger.debug("[viwo]-->[enter QueryForObject]");
  try
  {
   ConfigSelect configSelect =(ConfigSelect)selectMap.get(selectId);
   if(configSelect!=null)
   {
    String sql = configSelect.getSql();
    String type = configSelect.getType();
    String param = configSelect.getParam();
          if(paramObject.getClass() != Class.forName(param))
          {
           return null;
          }
          String[] sqls = sql.split("#");
          if(sqls.length>1)
          {
           for(int i=0;i            {
            if(i%2!=0)
            {
             String tmpValue = BeanUtils.getProperty(paramObject, sqls[i]);
             sql = sql.replaceFirst("#"+sqls[i]+"#", "'"+tmpValue+"'");
            }
           }
          }
          logger.debug("[viwo]-->[QueryForObject]-->[sql:]"+sql);
    //PreparedStatement ps = connection.prepareStatement(sql);
          ResultSet rs = statement.executeQuery(sql);
    ResultSetMetaData meta =  rs.getMetaData();
       int columnCount = meta.getColumnCount();
       if(rs.next())
       {
        Object newItem = Class.forName(type).newInstance();
        for(int i=1;i<=columnCount;i++)
        {
         Object rsItem = null;
         String columnType = meta.getColumnTypeName(i);
         if(columnType.equals("numeric"))
          rsItem = new Double(rs.getDouble(meta.getColumnName(i)));
         else if(columnType.equals("int"))
          rsItem = new Integer(rs.getInt(meta.getColumnName(i)));
         else
          rsItem = rs.getString(meta.getColumnName(i));

         BeanUtils.setProperty(newItem, meta.getColumnName(i), rsItem);
        }
        return newItem;
       }
   }

  }
  catch (Exception e)
  {
   logger.error("[viwo]-->[QueryForObject]-->"+e.getMessage());
   throw new Exception(e);
  }
  //如果沒有查出結果或者selectId非法則返回null。
  return null;
 }

    /**
     * execute a statement from sqlmap-config.xml by executeId
     *
     * fit for this sql: insert into users values(#username#,#password#)
     *
     * the " #name#, #password# " will be set value by paramObject
     *
     * @param selectId
     * @param paramObject
     * @return int
     * @throws Exception
     */
 public int executeStatement(String executeId,Object paramObject) throws Exception
 {
  logger.debug("[viwo]-->[enter executeStatement]");
  try
  {
   ConfigExecute configExecute =(ConfigExecute)executeMap.get(executeId);
   if(configExecute!=null)
   {
    String sql = configExecute.getSql();
    String param = configExecute.getParam();
          if(paramObject.getClass() != Class.forName(param))
          {
           return -1;
          }
          String[] sqls = sql.split("#");
          if(sqls.length>1)
          {
           for(int i=0;i            {
            if(i%2!=0)
            {
             String tmpValue = BeanUtils.getProperty(paramObject, sqls[i]);
             sql = sql.replaceFirst("#"+sqls[i]+"#", "'"+tmpValue+"'");
            }
           }
          }
          logger.debug("[viwo]-->[executeStatement]-->[sql:]"+sql);
    //PreparedStatement ps = connection.prepareStatement(sql);
    return statement.executeUpdate(sql);
   }

  }
  catch (Exception e)
  {
   e.printStackTrace();
   logger.error("[viwo]-->[executeStatement]-->"+e.getMessage());
   //throw new Exception(e);
  }
  return -1;
 }

 public void addSelect(ConfigSelect configSelect)
 {
  selectMap.put(configSelect.getId(), configSelect);
 }
 public void addExecute(ConfigExecute configExecute)
 {
  executeMap.put(configExecute.getId(), configExecute);
 }

 public Map getSelectMap() {
  return selectMap;
 }

    /**
     * a static synchronized method to get the SqlMapConfig from a gived path
     *
     * this method will initialize the properity connection
     *
     * @param path
     * @return SqlMapConfig
     * @throws Exception
     */
 public static synchronized SqlMapConfig getInstance(String path) throws Exception
 {
  logger.info("[viwo]-->[enter getInstance]-->[path:]"+path);
  SqlMapConfig sqlMapConfig = null;
  if(configMap.get(path)!=null)
  {
   sqlMapConfig = (SqlMapConfig)configMap.get(path);
  }
  else
  {
      Digester digester = new Digester();
         digester.setValidating(false);
         digester.addObjectCreate("sqlmap-config", "com.viwo.sqlmap.config.SqlMapConfig");

         digester.addObjectCreate("sqlmap-config/select", "com.viwo.sqlmap.config.ConfigSelect");
         digester.addSetProperties("sqlmap-config/select");
         digester.addCallMethod("sqlmap-config/select/sql", "setSql", 0);
         digester.addSetNext("sqlmap-config/select", "addSelect", "com.viwo.sqlmap.config.ConfigSelect");

            digester.addObjectCreate("sqlmap-config/execute", "com.viwo.sqlmap.config.ConfigExecute");
         digester.addSetProperties("sqlmap-config/execute");
         digester.addCallMethod("sqlmap-config/execute/sql", "setSql", 0);
         digester.addSetNext("sqlmap-config/execute", "addExecute", "com.viwo.sqlmap.config.ConfigExecute");

         try
         {
          sqlMapConfig = (SqlMapConfig)digester.parse(Thread.currentThread().getContextClassLoader().getResource("/"+path).getFile());
          configMap.put(path, sqlMapConfig);
         }
      catch (Exception e)
      {
       logger.error("[viwo]-->[getInstance]-->"+e.getMessage());
       throw new Exception(e);
      }
  }

  sqlMapConfig.connection = ConnectionFactory.getConnection();
  sqlMapConfig.statement = sqlMapConfig.connection.createStatement();

     return sqlMapConfig;

 }

    /**
     * begin transaction
     * @throws Exception
     */
 public void beginTransaction() throws Exception
 {
  try
  {
   this.connection.setAutoCommit(false);
  }
  catch (SQLException e)
  {
   logger.error("[viwo]-->[beginTransaction]--beginTransaction error");
   throw new Exception(e);
  }
 }

    /**
     * commit transaction
     * @throws Exception
     */
 public void commitTransaction() throws Exception
 {
  try
  {
   this.connection.commit();
  }
  catch (SQLException e)
  {
   logger.error("[viwo]-->[commitTransaction]--commitTransaction error");
   throw new Exception(e);
  }
 }
    /**
     * rollback transaction
     * @throws Exception
     */
 public void rollbackTransaction() throws Exception
 {
  try
  {
   this.connection.rollback();
  }
  catch (SQLException e)
  {
   logger.error("[viwo]-->[rollbackTransaction]--rollbackTransaction error");
   throw new Exception(e);
  }
 }
    /**
     * close the property of connection
     */
 public void closeConnection()
 {
  if(statement!=null)
  {
  try {
    statement.close();
   }
   catch (SQLException e)
   {

   }
  }
  if(connection!=null)
  {
  try {
    connection.close();
   }
   catch (SQLException e)
   {

   }
  }
 }

}