catalogmanagerbean.java

用JBuilder+Jboos+mysql实现的EJB项目

package com.jdon.estore.catalog;

import javax.ejb.*;

import com.jdon.servicelocator.ejb.ServiceLocator;
import com.jdon.controller.events.EventModel;
import com.jdon.estore.model.Category;
import com.jdon.estore.catalog.dao.CatalogDAO;

import com.jdon.sequence.SequenceGeneratorLocalHome;
import com.jdon.sequence.SequenceGeneratorLocal;

import com.jdon.controller.model.PageIterator;
import java.util.*;

import com.jdon.estore.JNDINames;
import org.apache.log4j.Logger;

public class CatalogManagerBean implements SessionBean {

  private final static Logger logger = Logger.getLogger(CatalogManagerBean.class);

  SessionContext sessionContext;
  private CategoryHome chome;
  private CategoryDetailsHome cdhome;
  private SequenceGeneratorLocalHome sequenceHome;
  private CatalogEJBLocalHome catalogEJBHome;


  private int categoryAllCount = 0;
  private Map pageIteratorCache = new HashMap();

  public void ejbCreate() throws CreateException {
    try {
      ServiceLocator sl = new ServiceLocator();
      chome = (CategoryHome) sl.getLocalHome(JNDINames.
          CATEGORY_HOME);

      cdhome = (CategoryDetailsHome) sl.getLocalHome(JNDINames.
          CATEGORY_DETAILS_HOME);

      sequenceHome = (SequenceGeneratorLocalHome)sl.getLocalHome(
          JNDINames.SEQUENCEGENERATOR_HOME);

  catalogEJBHome = (CatalogEJBLocalHome)sl.getLocalHome(JNDINames.CATALOG_EJBHOME);


    } catch (Exception ex) {
      logger.error("create error:" + ex);
      throw new CreateException();
    }
  }

  public int getNewId(String name) {
    try {
      SequenceGeneratorLocal seq = sequenceHome.create();
      return seq.nextSequenceNumber(name);
    } catch (Exception ex) {
      throw new EJBException("Error generating id for : " + name + ex);
    }
  }

  public void createCategory(EventModel em) throws Exception {
    Category category = (Category) em.getModel();
    try {
      String Id = Integer.toString(getNewId(JNDINames.SEQUENCE_NAME));

      CategoryLocal categoryLocal = chome.create(Id);
      CategoryDetails categoryDetails = cdhome.create(Id, category.getName(),
          category.getDescription());
      //设置Category与CategoryDetails的1:1关系
      categoryLocal.setCategoryDetails(categoryDetails);

      //因为新增了新的记录，数据库记录总数变化，复位为0
      categoryAllCount = 0;

      category.setCatId(Id); //Id是自动生产的，放入EvenModel中。

    } catch (Exception ex) {
      logger.error(ex);
      em.setErrors("db.error");
    }
  }

  public void updateCategory(EventModel em) throws Exception {
    Category category = (Category) em.getModel();
    try {
      logger.debug(" --> got categotyLocal by Id = " + category.getCatId());
      CategoryLocal categoryLocal = chome.findByPrimaryKey(category.getCatId());
      logger.debug(" --> got categotyDetails");
      CategoryDetails categoryDetails = categoryLocal.getCategoryDetails();
      categoryDetails.setName(category.getName());
      categoryDetails.setDescription(category.getDescription());
    } catch (Exception ex) {
      logger.error(ex);
      em.setErrors("db.error");
    }
  }

  //if cacasde delete is true , this will delete all product;
  public void deleteCategory(EventModel em) throws Exception {
    Category category = (Category) em.getModel();
    try {
      chome.remove(category.getCatId());
      //cacasde delete is true

      //因为删除了新的记录，数据库记录总数变化，复位为0
      categoryAllCount = 0;
    } catch (Exception ex) {
      logger.error(" --->> customer create error:" + ex);
      em.setErrors("db.error");
    }
  }

  public Category getCategoryById(String id) {
    logger.debug(" looking for  id=" + id);
    try {
      CatalogEJBLocal catalogEJB = catalogEJBHome.create();
      return catalogEJB.getCategory(id);
    } catch (FinderException ex) {
      logger.warn(ex);
    } catch (Exception ex) {
      logger.error(ex);
    }
    return null;
  }

  public Category getCategoryByName(String name) {
    logger.debug(" looking for  name=" + name);
    try {
      CategoryDetails categoryDetails = cdhome.findByName(name);
      Category category = getCategoryDeatils(categoryDetails);
      return category;
    } catch (FinderException ex) {
      logger.warn(ex);
    } catch (Exception ex) {
      logger.error(ex);
    }
    return null;

  }

  public Collection getCategoryByAll() {
    try {
      Collection categoryDetailsList = cdhome.findByAll();
      Iterator iter = categoryDetailsList.iterator();
      Collection list = new ArrayList();
      while (iter.hasNext()) {
        CategoryDetails categoryDetails = (CategoryDetails) iter.next();
        Category category = getCategoryDeatils(categoryDetails);
        list.add(category);
      }
      return list;
    } catch (FinderException ex) {
      logger.warn(ex);
    } catch (Exception ex) {
      logger.error(ex);
    }
    return null;

  }

  private Category getCategoryDeatils(CategoryDetails categoryDetails) {
    Category category = new Category();
    category.setCatId(categoryDetails.getCatId());
    category.setName(categoryDetails.getName());
    category.setDescription(categoryDetails.getDescription());
    return category;

  }

  public PageIterator getCategories(int start, int count) {
    PageIterator pageIterator = null;
    try {
      String pIKey = getPIKey(start);//获得key
      //首先从缓冲中获取
      pageIterator = (PageIterator)pageIteratorCache.get(pIKey);
      if (pageIterator == null){
        //从数据库读取
        CatalogEJBLocal catalogEJB = catalogEJBHome.create();
        pageIterator = catalogEJB.getCategories(start, count);
        pageIteratorCache.put(pIKey, pageIterator);
      }else{
         logger.debug("read pageIterator from cache ..........");
      }
      pageIterator.setAllCount(getCategoryAllCount());
    } catch (Exception ex) {
      logger.warn("getCategories error: " + ex);
    }
    return pageIterator;
  }

  private String getPIKey(int start) {
    StringBuffer buffer = new StringBuffer("PageIterator");
    buffer.append(start);

    return buffer.toString();
  }

  public int getCategoryAllCount() {
    try {
      if (categoryAllCount == 0){
        CatalogEJBLocal catalogEJB = catalogEJBHome.create();
        categoryAllCount = catalogEJB.getCategoryAllCount();
      }else{
        logger.debug("read categoryAllCount from cache ..........");
      }
    } catch (Exception ex) {
      logger.error("getCategoryAllCount() error");
    }
    return categoryAllCount;

  }

  public void ejbRemove() {
  /**@todo Complete this method*/
  }

  public void ejbActivate() {
  /**@todo Complete this method*/
  }

  public void ejbPassivate() {
  /**@todo Complete this method*/
  }

  public void setSessionContext(SessionContext sessionContext) {
    this.sessionContext = sessionContext;
  }
}