moduledao.java

来自「struts2 spring2.5 jpa hibernate 权限管理系统源代」· Java 代码 · 共 81 行

package sunyang.module.dao;

import java.util.List;
import javax.persistence.*;

import sunyang.module.domain.Module;
import sunyang.persistence.EntityManagerHelper;

public class ModuleDAO implements IModuleDAO {
	// 声明静态常量
	public static final String MODULENAME = "modulename";

	// 得到实体管理器
	private EntityManager getEntityManager() {
		return EntityManagerHelper.getEntityManager();
	}

	// 新增数据
	public void save(Module entity) {
		EntityManagerHelper.beginTransaction();
		try {
			getEntityManager().persist(entity);
			EntityManagerHelper.commit();
		} catch (RuntimeException re) {
			EntityManagerHelper.rollback();
			throw re;
		}
	}

	// 删除数据
	public void delete(Module entity) {
		EntityManagerHelper.beginTransaction();
		try {
			entity = getEntityManager().getReference(Module.class,
					entity.getId());
			getEntityManager().remove(entity);
			EntityManagerHelper.commit();
		} catch (RuntimeException re) {
			EntityManagerHelper.rollback();
			throw re;
		}
	}

	// 修改数据
	public Module update(Module entity) {
		EntityManagerHelper.beginTransaction();
		try {
			Module result = getEntityManager().merge(entity);
			EntityManagerHelper.commit();
			return result;
		} catch (RuntimeException re) {
			EntityManagerHelper.rollback();
			throw re;
		}
	}

	// 通过id查询数据
	public Module findById(Integer id) {
		try {
			Module instance = getEntityManager().find(
					Module.class, id);
			return instance;
		} catch (RuntimeException re) {
			throw re;
		}
	}

	// 查询所有数据
	@SuppressWarnings("unchecked")
	public List<Module> findAll() {
		try {
			final String queryString = "select m from Module m";
			Query query = getEntityManager().createQuery(queryString).setHint(
					"toplink.refresh", true);
			return query.getResultList();
		} catch (RuntimeException re) {
			throw re;
		}
	}

}