如何编写对一个表操作的DAO和Entity

1， 实体的编写（基于Hibernate3注解）

package com.tr.geda.evm.common.entity;

import java.util.Date;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Transient;


@Entity
@Table(name = "USER_DETAILS")
public class UserDetails {
	@Id
	private String username;
	private String password;
	private String password_change;
	private Date password_edit_date;
	private Integer password_fails;
	private String enabled;
	private String permissioner;
	private String user_type;
	private String central_user;
	@Transient
	private boolean tdnUser = false;
	
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public String getPassword_change() {
		return password_change;
	}
	public void setPassword_change(String passwordChange) {
		password_change = passwordChange;
	}
	public Date getPassword_edit_date() {
		return password_edit_date;
	}
	public void setPassword_edit_date(Date passwordEditDate) {
		password_edit_date = passwordEditDate;
	}
	public Integer getPassword_fails() {
		return password_fails;
	}
	public void setPassword_fails(Integer passwordFails) {
		password_fails = passwordFails;
	}

	public String getEnabled() {
		return enabled;
	}
	public void setEnabled(String enabled) {
		this.enabled = enabled;
	}
	public String getPermissioner() {
		return permissioner;
	}
	public void setPermissioner(String permissioner) {
		this.permissioner = permissioner;
	}
	public String getUser_type() {
		return user_type;
	}
	public void setUser_type(String userType) {
		user_type = userType;
	}
	public String getCentral_user() {
		return central_user;
	}
	public void setCentral_user(String centralUser) {
		central_user = centralUser;
	}
	public boolean isTdnUser() {
		return tdnUser;
	}
	public void setTdnUser(boolean tdnUser) {
		this.tdnUser = tdnUser;
	}
	
	

}

2， DAO的编写基于Hibernate3

package com.tr.geda.evm.dao.hibernate;

import java.util.List;

import org.hibernate.Query;
import org.springframework.context.annotation.Scope;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import org.springframework.stereotype.Repository;

import com.tr.geda.evm.common.entity.UserDetails;

@Repository
@Scope("singleton")
public class LoginDao extends HibernateDaoSupport {
	public String getDBName() {
		String sql = "select name from v$database";
		Query query = getSession().createSQLQuery(sql);
		return query.list().get(0).toString();
	}

	public String getHostName() {
		String sql = "select host_name from v$instance";
		Query query = getSession().createSQLQuery(sql);
		return query.list().get(0).toString();
	}
	
	public UserDetails getUserByName(String user) {
		UserDetails userDetail = null;
		String hql = "select a from UserDetails a where a.username = ?";
		List list = this.getHibernateTemplate().find(hql, user);
		if(list == null || list.size() == 0)
		{
			return null;
		}
		return (UserDetails)list.get(0);
		
	}
	
	
}