subjecthibernatedaoimpl.java

基于Ajax+Spring+Hibernate开发的个性化定制系统源代码

package com.individaution.dao.hibernate;

import java.util.ArrayList;
import java.util.List;

import org.springframework.dao.DataAccessException;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import com.individaution.bean.Subject;
import com.individaution.dao.ISubjectDAO;
import com.individaution.resource.AppContext;


/**
 * 
 * @author liuyu
 *2007-7-26
 */
public class SubjectHibernateDAOImpl extends HibernateDaoSupport implements
		ISubjectDAO {

	private static final String LOAD_SUBJECT_LEVELONE = "from Subject sub where sub.subjectlevel='0'";

	private static final String LOAD_SUBJECT_LEVELTWO_BYID = "from Subject sub where sub.subjectlevel='2' and sub.subject=?";
	
	private static ISubjectDAO  iSubjectDAO;

	public SubjectHibernateDAOImpl() {
  
	
	}

	
	public static ISubjectDAO getInstance(){
		
	 if( iSubjectDAO==null){
		 iSubjectDAO=(ISubjectDAO)AppContext.getInstance().getAppContext().getBean("subjectDAO"); 
		 }
	 return iSubjectDAO ;
	}
	
	/*
	 * （非 Javadoc）
	 * @see com.individaution.dao.ISubjectDAO#getSubjectById(java.lang.String)
	 */
	public Subject getSubjectById(String id) {
		try {
			return (Subject) getHibernateTemplate().get(Subject.class, id);
		} catch (DataAccessException ex) {
			return null;
		}
	}

	
	/*
	 * （非 Javadoc）
	 * @see com.individaution.dao.ISubjectDAO#getSubjectsLevelOne()
	 */
	public List getSubjectsLevelOne() {

		List l = (List) getHibernateTemplate().find(LOAD_SUBJECT_LEVELONE);
		if (l.size() == 0) {
			return null;
		} else {
			return  l;
		}
	}

	/*
	 * （非 Javadoc）
	 * @see com.individaution.dao.ISubjectDAO#getSubjectsLevelTwoByParent(com.individaution.bean.Subject)
	 */
	public List getSubjectsLevelTwoByParent(Subject sub) {

		List l = (List) getHibernateTemplate().find(LOAD_SUBJECT_LEVELTWO_BYID,
				sub);
		if (l.size() == 0) {
			return null;
		} else {
			return  l;
		}
	}

}