Cougaar学习笔记之---定制特殊的AspectType和AspectValue

 动机：在Cougaar中，已经提供了一些标准的AspectType和AspectValue。但在实际的应用中，可能需要定制特殊的
AspectType和AspectValue.
  实现步骤：
  1、在Domain类中定义特殊的AspectValue和AspectType相关的信息, 并注册AspectValue相应的Factory
   Domain类要继承DomainAdapter, 核心代码如下:
public class PersistenceDomain extends DomainAdapter {
    //Aspect Type Factories
    /** DbChange Aspect */
    Factory DbChange = new Factory() {
            public int getKey() {return PersistenceDomainUtil.DBCHANGE_ASPECT;}
            public String getName() {return "DBCHANGE";}
            public AspectValue newAspectValue(Object o) {
                return DoubleAspectValue.create(PersistenceDomainUtil.DBCHANGE_ASPECT, o);
            }
        };
    /**
     * Load the domain and custom aspect types used throughout BOL
     */
    public void load() {
        super.load();
        loadCustomAspectTypes();
    }
    /**
     * Load Custom AspectType Factories
     */
    private void loadCustomAspectTypes() {
        if (AspectType.registry.get(PersistenceDomainUtil.DBCHANGE_ASPECT) == null) {
            AspectType.registry.registerFactory(DbChange);
        }

    }
  ....
}

 其中PersistenceDomainUtil.DBCHANGE_ASPECT的值是:
   public static final int DBCHANGE_ASPECT = AspectType.ASPECT_STRINGS.length + 2;
 
  2、注册Domain类
   在LDMDomains.ini文件中增加一项：
PersistenceDomain=com.justep.business.content.model.persistence.domain.PersistenceDomain