commandmap.java

java实现的可配置的工作流引擎,采用jsp+javabean实现

package com.hongsoft.res.util;

import java.io.File;
import java.util.HashMap;

import com.hongsoft.agile.Global;
import com.hongsoft.res.dispatcher.BaseCommand;

/** 
 * <p>Description: 命令文件配置信息的映射</p> 
 */

public class CommandMap {
  private static HashMap cmdMap;
  private static PropertiesReader pr = null;

  private static void loadProperties(){
    if(pr==null){
      pr = new PropertiesReader(Global.getConfigPath() + File.separator + "commandmap.properties");
      cmdMap = new HashMap();
    }
  }
  /**
   * 通过cmdName创建一个BaseCommand子类的实例
   * @param cmdName Command name
   * @return BaseCommand子类的实例
   * @throws BaseException
   */
  public static BaseCommand getCommand(String cmdName) throws Exception {
    loadProperties();
    String className = pr.getProperty(cmdName);
    BaseCommand baseCmd = null;
    try {
      if (cmdMap.containsKey(cmdName)) {
        baseCmd = (BaseCommand) cmdMap.get(cmdName);
      }
      else {
        Class c = Class.forName(className);
        baseCmd = (BaseCommand) c.newInstance();
        cmdMap.put(cmdName, baseCmd);
      }
    }
    catch (ClassNotFoundException ex) {
    }
    catch (IllegalAccessException ex) {
    }
    catch (InstantiationException ex) {
    }
    return baseCmd;
  }
}