大家看看这个hibernate对数据库操作的公用方法库(写的怎么样)?

import java.io.Serializable;
import java.sql.SQLException;
import java.util.List;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.springframework.orm.ObjectRetrievalFailureException;
import org.springframework.orm.hibernate3.HibernateCallback;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

/**
 * This class serves as the Base class for all other DAOs - namely to hold
 * common CRUD methods that they might all use. You should only need to extend
 * this class when your require custom CRUD logic.
 * <p>
 * To register this class in your Spring context file, use the following XML.
 * 
 * <pre>
 *      &lt;bean id=&quot;fooDao&quot; class=&quot;com.soft863.bbs.dao.hibernate.GenericDaoHibernate&quot;&gt;
 *          &lt;constructor-arg value=&quot;com.soft863.bbs.model.Foo&quot;/&gt;
 *          &lt;property name=&quot;sessionFactory&quot; ref=&quot;sessionFactory&quot;/&gt;
 *      &lt;/bean&gt;
 * </pre>
 * 
 * @author <a href="mailto:[e-mail]">Bryan Noll</a>
 */
public class GenericDaoHibernate<T, PK extends Serializable> extends
		HibernateDaoSupport implements GenericDao<T, PK> {
	protected final Log log = LogFactory.getLog(getClass());

	private Class<T> persistentClass;

	public GenericDaoHibernate() {

	}

	public GenericDaoHibernate(Class<T> persistentClass) {
		this.persistentClass = persistentClass;
	}

	public void setPersistentClass(Class<T> persistentClass) {
		this.persistentClass = persistentClass;
	}

	@SuppressWarnings("unchecked")
	public List<T> getAll() {
		return super.getHibernateTemplate().loadAll(this.persistentClass);
	}

	@SuppressWarnings("unchecked")
	private T get(PK id) {
		T entity = (T) super.getHibernateTemplate().get(this.persistentClass,
				id);

		if (entity == null) {
			log.warn("Uh oh, '" + this.persistentClass + "' object with id '"
					+ id + "' not found...");
			throw new ObjectRetrievalFailureException(this.persistentClass, id);
		}

		return entity;
	}

	@SuppressWarnings("unchecked")
	private boolean exists(PK id) {
		T entity = (T) super.getHibernateTemplate().get(this.persistentClass,
				id);
		if (entity == null) {
			return false;
		} else {
			return true;
		}
	}

	private void remove(PK id) {
		this.remove(this.get(id));
	}

	public T save(T object) {
		super.getHibernateTemplate().saveOrUpdate(object);
		return object;
	}

	private void remove(Object object) {
		super.getHibernateTemplate().delete(object);
	}

	@SuppressWarnings("unchecked")
	public Object getObject(final Class persistentClass, final String where) {
		List list = this.getHibernateTemplate().executeFind(
				new HibernateCallback() {
					public Object doInHibernate(Session s)
							throws HibernateException, SQLException {
						StringBuffer sql = new StringBuffer("from "
								+ persistentClass.getName() + " p ");
						if (StringUtils.isNotBlank(where)) {
							if (where.trim().startsWith("where ")) {
								sql.append(where);
							} else {
								sql.append(" where ").append(where);
							}
						}
						Query q = s.createQuery(sql.toString());
						return q.list();
					}
				});
		if (list != null) {
			// 如果取到唯一一个值，返回
			if (list.size() == 1) {
				return list.get(0);
			} else if (list.size() > 0) {
				// 如果多余一个值，输出错误，返回null
				// System.out.println("[warn]:getObject("+persistentClass.getName()+",\""+where+"\"):根据唯一条件得到多于一个的值，请检查！");
				return null;
			}
		}
		return null;
	}

	@SuppressWarnings("unchecked")
	public List getObjs(final String hsql) {
		
		return getObjs(hsql,-1,-1);
	}
	public List getObjs(final String hsql,final int firstResult, final int maxResult) {
		List list = this.getHibernateTemplate().executeFind(
				new HibernateCallback() {
					public Object doInHibernate(Session s)
							throws HibernateException, SQLException {
						Query q = s.createQuery(hsql);
						if (firstResult >= 0 && maxResult >= 0) {
							q.setFirstResult(firstResult);
							q.setMaxResults(maxResult);
						}
						return q.list();
					}
				});
		return list;
	}

	public List getObjs(final String hsql, final int num) {
		List list = this.getHibernateTemplate().executeFind(
				new HibernateCallback() {
					public Object doInHibernate(Session s)
							throws HibernateException, SQLException {
						Query q = s.createQuery(hsql);
						if (num >= 0) {
							q.setFirstResult(0);
							q.setMaxResults(num);
						}
						return q.list();
					}
				});
		return list;
	}

	public boolean exists(Class<T> persistentClass, PK id) {
		synchronized (this) {
			this.setPersistentClass(persistentClass);
			return this.exists(id);
		}
	}

	public T get(Class<T> persistentClass, PK id) {
		synchronized (this) {
			this.setPersistentClass(persistentClass);
			return this.get(id);
		}
	}

	public void remove(Class<T> persistentClass, PK id) {

		synchronized (this) {
			this.setPersistentClass(persistentClass);
			this.remove(id);
		}

	}

	@SuppressWarnings("unchecked")
	public List getListBySql(String sql) {
		SQLQuery a = this.getSession().createSQLQuery(sql);
		return a.list();
	}

	public List getObjstBySql(final String sql, final int firstResult, final int maxResult) {
		
		List list = this.getHibernateTemplate().executeFind(
				new HibernateCallback() {
					public Object doInHibernate(Session s)
							throws HibernateException, SQLException {
						Query q = s.createSQLQuery(sql);
						if (firstResult >= 0 && maxResult >= 0) {
							q.setFirstResult(firstResult);
							q.setMaxResults(maxResult);
						}
						return q.list();
					}
				});
		return list;
	}
	
}

***************************分割线(下面是接口)***************************

import java.io.Serializable;
import java.util.List;


/**
 * Generic DAO (Data Access Object) with common methods to CRUD POJOs.
 *
 * <p>Extend this interface if you want typesafe (no casting necessary) DAO's for your
 * domain objects.
 *
 * @author <a href="mailto:[e-mail]">Bryan Noll</a>
 */
public interface GenericDao <T, PK extends Serializable> {

	public void setPersistentClass(Class<T> persistentClass);
    /**
     * Generic method used to get all objects of a particular type. This
     * is the same as lookup up all rows in a table.
     * @return List of populated objects
     */
    public List<T> getAll();

    /**
     * Generic method to get an object based on class and identifier. An
     * ObjectRetrievalFailureException Runtime Exception is thrown if
     * nothing is found.
     *
     * @param id the identifier (primary key) of the object to get
     * @return a populated object
     * @see org.springframework.orm.ObjectRetrievalFailureException
     */
    public T get(Class<T> persistentClass,PK id);
    
    /**
     * Checks for existence of an object of type T using the id arg.
     * @param id
     * @return - true if it exists, false if it doesn't
     */
    public boolean exists(Class<T> persistentClass,PK id);

    /**
     * Generic method to save an object - handles both update and insert.
     * @param object the object to save
     */
    public T save(T object);

    /**
     * Generic method to delete an object based on class and id
     * @param id the identifier (primary key) of the object to remove
     */
    public void remove(Class<T> persistentClass, PK id);
    
	/**
	 * Generic method to get an object based on class and identifier. An
	 * ObjectRetrievalFailureException Runtime Exception is thrown if nothing is
	 * found.
	 * 
	 * @param clazz
	 *            model class to lookup
	 * @param id
	 *            the identifier (primary key) of the class
	 * @return a populated object
	 * @see org.springframework.orm.ObjectRetrievalFailureException
	 */
	
	/**
	 * 根据where条件，得到唯一的po对象。如果结果多于一个，返回null。并在后台输出错误。
	 * @param persistentClass	该po的持久化class
	 * @param where	查询的where条件，类似于[p.name='22']
	 * @return 通过查询条件得到的唯一对象
	 */
	public Object getObject(Class<T> persistentClass, String where);
	/**
	 * 根据hsql语句，返回查询结果。
	 * @param hsql	hsql语句，类似于[from com.hnjz.core.User u where u.name like 'admin%']
	 * @return 通过查询条件得到hibernate的查询结果(List)
	 */
	@SuppressWarnings("unchecked")
	public List getObjs(String hsql);
	
	public List getObjs(String hsql,final int firstResult, final int maxResult);
	/**
	 * 返回前num个查询结果。
	 * @param hsql	hsql语句，类似于[from com.hnjz.core.User u where u.name like 'admin%']
	 * @param num 查询结果数量
	 * @return 通过查询条件得到hibernate的查询结果(List)
	 */
	public List getObjs(String hsql,int num);
	
	public List getListBySql(String sql);
	
	public List getObjstBySql(String sql,final int firstResult, final int maxResult);
}