hibernate 的介绍与编写的程序

程序员文章站 2022-06-03 21:22:03

...

1 简答题（写概念，思原理）
1.1 Hibernate框架作用
参考答案：
hibernate是一个数据访问框架(持久层框架),在项目中利用Hibernate框架可以实现对数据库的增删改查操作,为业务层构建一个持久层
1.2 Hibernate框架原理–(ORM)
参考答案：
ORM–Object Relation Mapping,对象关系映射.
主要思想:将Java对象与关系表进行自动映射,这样可以将对象直接更新到数据库;查询时,可以自动将数据表记录封装成Java对象.
1.3 Hibernate主要的体系结构
参考答案：
a.实体类(Xxx),可以有n个
与数据表对应,用于封装数据表的一行记录
b.XML映射文件(Xxx.hbm.xml),可以有n个
用于描述实体类与数据表之间的对应关系；类属性与表字段之间的对应关系。
c.主配置文件(hibernate.cfg.xml),可以有1个
用于指定连接数据库的参数,框架参数等
1.4 Hibernate开发的基本步骤
参考答案：
a.引入hibernate框架开发包
b. 添加Hibernate主配置文件
c. 根据数据表,编写实体类,映射文件
d. 利用Hibernate API操作实体对象
2 填空题（读代码、加注释）
2.1 阅读下面的代码，并在指定位置添加注释。

<?xml version="1.0" encoding="utf-8"?>
“http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd”>
<!—此句代码的作用是（将类Fee与数据库表COST做映射）–>

 <class name="com.tarena.netctoss.pojo.Fee" table="COST">

  <!—此句代码的作用是（ Fee类的id属性和数据库表的ID列做映射 ）-->

     <id name="id" column="ID" type="integer">

      <!—此句代码的作用是（ 使用序列作为主键的生产方式 ）-->

```
        <generator class="sequence">
```

            <param name="sequence">FEE_SEQ</param>

```
        </generator>
```
```
    </id>
```

    <property name="feeName" column="NAME"

```
        type="string">
```
```
    </property>
```

    <property name="baseDuration" column="BASE_DURATION"

```
        type="integer">
```
```
    </property>
```

    <property name="baseCost" column="BASE_COST"

```
        type="float">
```
```
    </property>
```

    <property name="unitCost" column="UNIT_COST"

```
        type="float">
```
```
    </property>
```

    <property name="status" column="STATUS"

```
        type="string">
```
```
    </property>
```

    <property name="descr" column="DESCR"

```
        type="string">
```
```
    </property>
```

    <property name="costType" column="COST_TYPE"

```
        type="string">
```
```
    </property>
```

    <property name="createTime" column="CREATIME"

```
        type="date">
```
```
    </property>
```

    <property name="startTime" column="STARTIME"

```
        type="date">
```
```
    </property>
```
```
</class>
```

3 编程题（改代码，写代码）
3.1 重构“NETCTOSS登录检查拦截器”案例
重载Struts2的Day05的“NETCTOSS登录检查拦截器”案例，使用Hibernate实现修改和删除功能。
参考答案：
1.按照Struts2的Day02的“NETCTOSS资费的分页显示”案例中，拷贝工程的方法，拷贝struts05_2创建hibernate01_3工程。如图-4，图-5所示。

图- 4

图- 5
2.创建Fee.hbm.xml

<?xml version="1.0" encoding="utf-8"?>
“http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd”>

 <class name="com.tarena.netctoss.pojo.Fee" table="COST">

     <id name="id" column="ID" type="integer">

```
         <generator class="sequence">
```

             <param name="sequence">FEE_SEQ</param>

```
         </generator>
```
```
    </id>
```

    <property name="feeName" column="NAME"

```
        type="string">
```
```
    </property>
```

    <property name="baseDuration" column="BASE_DURATION"

```
        type="integer">
```
```
    </property>
```

    <property name="baseCost" column="BASE_COST"

```
        type="float">
```
```
    </property>
```

    <property name="unitCost" column="UNIT_COST"

```
        type="float">
```
```
    </property>
```

    <property name="status" column="STATUS"

```
        type="string">
```
```
    </property>
```

    <property name="descr" column="DESCR"

```
        type="string">
```
```
    </property>
```

    <property name="costType" column="COST_TYPE"

```
        type="string">
```
```
    </property>
```

    <property name="createTime" column="CREATIME"

```
        type="date">
```
```
    </property>
```

    <property name="startTime" column="STARTIME"

```
        type="date">
```
```
    </property>
```
```
</class>
```

3.创建hibernate.cfg.xml
40. <?xml version='1.0' encoding='UTF-8'?>
41.
44.
45.
46.
47.
48.
49.
50. org.hibernate.dialect.OracleDialect
51.
52.
53. jdbc:oracle:thin:@192.168.0.20:1521:tarena
54.
55. task
56. mistarena
57.
58. oracle.jdbc.driver.OracleDriver
59.
60.
61. true
62. true
63.
64.
65.
66.
4.修改FeeDAO,修改update方法，findById方法，deleteById方法，使用Hibernate操作数据库。
67. package com.tarena.netctoss.dao;
68.
69. import java.sql.Connection;
70. import java.sql.Date;
71. import java.sql.PreparedStatement;
72. import java.sql.ResultSet;
73. import java.util.ArrayList;
74. import java.util.List;
75.
76. import org.hibernate.Session;
77. import org.hibernate.Transaction;
78.
79. import com.tarena.netctoss.pojo.Fee;
80.
81. import com.tarena.netctoss.utils.ConnectionUtils;
82. import com.tarena.netctoss.utils.HibernateUitl;
83.
84. public class FeeDAO {
85. private static final String findAll =
86. “select ID, NAME, BASE_DURATION, BASE_COST, UNIT_COST, CREATIME, STARTIME, STATUS, DESCR,COST_TYPE from (” +
87. "select rownum r, ID, NAME, BASE_DURATION, BASE_COST, UNIT_COST, CREATIME, STARTIME, STATUS, DESCR,COST_TYPE from COST where rownum < ?) a " +
88. "where a.r > ? “;
89. private static final String getTotalPages = “select count(*) from COST”;
90. private static final String findByName = “select ID, NAME, BASE_DURATION, BASE_COST, UNIT_COST, CREATIME, STARTIME, STATUS, DESCR,COST_TYPE from COST where NAME=?”;
91. // private static final String findById = “select ID, NAME, BASE_DURATION, BASE_COST, UNIT_COST, CREATIME, STARTIME, STATUS, DESCR,COST_TYPE from COST where ID=?”;
92. // private static final String deleteById = “delete from COST where ID=?”;
93. // private static final String update =“update COST set NAME=?,BASE_DURATION=?,BASE_COST=?,UNIT_COST=?,”
94. // + " DESCR=?,COST_TYPE=? where ID=?”;
95.
96. public void update(Fee fee){
97. Session session = HibernateUitl.getSession();
98. Transaction tx = session.beginTransaction();
99. fee.setCreateTime(new Date(System.currentTimeMillis()));
100. session.update(fee);
101. tx.commit();
102. session.close();
103. }
104.
105. public Fee findById(int id){
106. Session session = HibernateUitl.getSession();
107. Fee fee = (Fee)session.get(Fee.class, id);
108. session.close();
109. return fee;
110. }
111.
112. public Fee findByName(String name){
113. Connection con = null;
114. PreparedStatement stmt = null;
115. ResultSet rs = null;
116. try {
117. con = ConnectionUtils.openConnection();
118. stmt = con.prepareStatement(findByName);
119. stmt.setString(1, name);
120. rs = stmt.executeQuery();
121. Fee fee = null;
122. if (rs.next()) {
123. fee = new Fee();
124. fee.setId(rs.getInt(“ID”));
125. fee.setFeeName(rs.getString(“NAME”));
126. fee.setBaseDuration(rs.getInt(“BASE_DURATION”));
127. fee.setBaseCost(rs.getFloat(“BASE_COST”));
128. fee.setUnitCost(rs.getFloat(“UNIT_COST”));
129. fee.setCreateTime(rs.getDate(“CREATIME”));
130. fee.setStartTime(rs.getDate(“STARTIME”));
131. fee.setStatus(rs.getString(“STATUS”));
132. fee.setDescr(rs.getString(“DESCR”));
133. fee.setCostType(rs.getString(“COST_TYPE”));
134. }
135. return fee;
136. } catch (Exception e) {
137. e.printStackTrace();
138. throw new RuntimeException(e);
139. }finally{
140. ConnectionUtils.closeConnection();
141. }
142. }
143.
144. public void deleteById(int id){
145. //创建fee对象
146. Fee fee = new Fee();
147. fee.setId(id);
148. //删除
149. Session session = HibernateUitl.getSession();
150. Transaction tx = session.beginTransaction();
151. session.delete(fee);
152. tx.commit();
153. session.close();
154. }
155.
156. public int getTotalPages(int pageSize) {
157. Connection con = null;
158. PreparedStatement stmt = null;
159. ResultSet rs = null;
160. try {
161. con = ConnectionUtils.openConnection();
162. stmt = con.prepareStatement(getTotalPages);
163. rs = stmt.executeQuery();
164. rs.next();
165. int totalRows = rs.getInt(1);
166. if (totalRows % pageSize == 0) {
167. return totalRows / pageSize;
168. } else {
169. return totalRows / pageSize + 1;
170. }
171.
172. } catch (Exception e) {
173. e.printStackTrace();
174. throw new RuntimeException(e);
175. }finally{
176. ConnectionUtils.closeConnection();
177. }
178. }
179.
180.
181. public List findAll(int page,int pageSize) {
182. Connection con = null;
183. PreparedStatement stmt = null;
184. ResultSet rs = null;
185. try {
186. con = ConnectionUtils.openConnection();
187. stmt = con.prepareStatement(findAll);
188. int begin = (page-1)pageSize;
189. int end = pagepageSize+1;
190. stmt.setInt(1, end);
191. stmt.setInt(2, begin);
192. rs = stmt.executeQuery();
193. List list = new ArrayList();
194. while (rs.next()) {
195. Fee fee = new Fee();
196. fee.setId(rs.getInt(“ID”));
197. fee.setFeeName(rs.getString(“NAME”));
198. fee.setBaseDuration(rs.getInt(“BASE_DURATION”));
199. fee.setBaseCost(rs.getFloat(“BASE_COST”));
200. fee.setUnitCost(rs.getFloat(“UNIT_COST”));
201. fee.setCreateTime(rs.getDate(“CREATIME”));
202. fee.setStartTime(rs.getDate(“STARTIME”));
203. fee.setStatus(rs.getString(“STATUS”));
204. fee.setDescr(rs.getString(“DESCR”));
205. fee.setCostType(rs.getString(“COST_TYPE”));
206. list.add(fee);
207. }
208. return list;
209. } catch (Exception e) {
210. e.printStackTrace();
211. throw new RuntimeException(e);
212. }finally{
213. ConnectionUtils.closeConnection();
214. }
215.
216. }
217.
218. }
219.记记得关注哦

上一篇：用phpmailer类发送邮件的相关有关问题

下一篇： Oracle 10g的RAC 在线日志也放在共享磁盘上

hibernate 的介绍与编写的程序

PHP与已存在的Java应用程序集成_PHP

c程序如何编写x的y次方

Java位掩码控制权限与(&)或(|)非(~)、>的介绍

Spring MVC 与 CORS跨域的详细介绍

Mysql中的count()与sum()区别详细介绍

CentOS下搭建PHP环境与WordPress博客程序的全流程总结

c#中的interface abstract与virtual介绍

iOS开发之Quartz2D的介绍与使用详解

Java中的同步与异步详细介绍

浅析java程序中hibernate的应用总结