工具類：
1 public class H3Util {
2
3 private static final SessionFactory sessionFactory = buildSessionFactory();
4
5 private static SessionFactory buildSessionFactory() {
6 try {
7 //從類加載路徑中讀取hibernate.cfg.xml文件生成SessionFactory對象
8 return new Configuration().configure().buildSessionFactory();
9 } catch (Throwable ex) {
10 System.err.println("Initial SessionFactory creation failed." + ex);
11 throw new ExceptionInInitializerError(ex);
12 }
13 }
14
15 public static SessionFactory getSessionFactory() {
16 return sessionFactory;
17 }
18 }
View Code
基礎的增刪改查：
1 public class TestHibernate {
2
3 @Test
4 public void add() {
5 SessionFactory sessionFactory = H3Util.getSessionFactory();
6 Session session = sessionFactory.openSession();
7 Transaction transaction = session.beginTransaction();
8 for (int i = 0; i < 20; i++) {
9 session.save(new User(null, "test"+i, "123456", new Date(), 1, 1000.0f));
10 }
11 transaction.commit();
12 session.close();
13 System.out.println("成功");
14 }
15
16 @Test
17 public void find() {
18 SessionFactory sessionFactory = H3Util.getSessionFactory();
19 Session session = sessionFactory.openSession();
20 System.out.println("+++++++++");
21 User user = (User)session.get(User.class, 1);
22 System.out.println("======");
23 System.out.println(user);
24 session.close();
25 }
26
27 @Test
28 public void del() {
29 SessionFactory sessionFactory = H3Util.getSessionFactory();
30 Session session = sessionFactory.openSession();
31 Transaction transaction = session.beginTransaction();
32 User user = (User)session.get(User.class, 2);
33 session.delete(user);
34 transaction.commit();
35 session.close();
36 System.out.println("成功"+user);
37 }
38
39 @Test
40 public void update() {
41 SessionFactory sessionFactory = H3Util.getSessionFactory();
42 Session session = sessionFactory.openSession();
43 Transaction transaction = session.beginTransaction();
44 User user = (User)session.get(User.class, 1);
45 user.setPassword("111111");
46 session.update(user);
47 transaction.commit();
48 session.close();
49 System.out.println("成功"+user);
50 }
51
52 @Test
53 public void findList() {
54 SessionFactory sessionFactory = H3Util.getSessionFactory();
55 Session session = sessionFactory.openSession();
56 String hql = "from User";
57 Query query = session.createQuery(hql);
58 @SuppressWarnings("unchecked")
59 List<User> uList = query.list();
60 for (User user : uList) {
61 System.out.println(user);
62 }
63 session.close();
64 }
65
66 }
View Code
測試hibernate的對象狀態：
1 /**
2 * @author nunu
3 * 測試 hibernate 對象
4 */
5 public class TestHibernateObject {
6
7 /**
8 * 共有三種狀態：
9 * 1、瞬時對象：TO 直接new對象
10 * 特點：
11 * 1、不受hibernate管理（session管理）
12 * 2、沒有OID
13 * 2、持久化對象：PO
14 * 特點：
15 * 1、受hibernate管理（session管理）
16 * 2、有OID
17 * 3、離線（托管）對象：DO
18 * 特點：
19 * 1、曾經受過hibernate管理，現在不受管理的（session）
20 * 2、有OID
21 */
22 @Test
23 public void status(){
24 SessionFactory sf = H3Util.getSessionFactory();
25 Session session = sf.openSession();
26 Transaction ts = session.beginTransaction();
27 //user --> TO
28 User user = new User(null, "nnn", "1234568", new Date(), 0, 999.9f);
29 session.save(user);
30 ts.commit();
31 //session.close();
32 //user --> PO
33 System.out.println(user);
34 session.delete(user);
35 //user --> DO
36 System.out.println(user+"----");
37 }
38
39
40 /**
41 * session 中數據發生更改，若事務提交，數據庫中數據修改
42 * 若事務不提交，session關閉時，不會修改數據庫
43 */
44 @Test
45 public void addUser() {
46 SessionFactory sf = H3Util.getSessionFactory();
47 Session session = sf.openSession();
48 Transaction ts = session.beginTransaction();
49 /**
50 * PO:持久化對象--數據庫表中的記錄同步的對象，只要該對象發生任何改變，session關閉時都會同步該對象的狀態到數據庫中的表記錄上
51 User user = (User) session.get(User.class, "4028810d57c20db20157c20db5920013");
52 user.setUsername("wangwu");
53 */
54
55 //DO
56 //User user = new User("4028408157c0f5920157c0f593e100001", "wangwu", "12312", new SimpleDateFormat("yyyy-MM-dd").parse("2016-10-14"), 1, 1000.0f);
57 //user.setUsername("wangwu");
58
59 //DO--PO :session -->一定會發生sql語句
60 //session.update(user);
61
62 //PO
63 User user = (User) session.get(User.class, "4028810d57c20db20157c20db5920013");
64
65 //PO--TO
66 session.delete(user);
67
68 /**
69 * 若不提交事務不會進行數據庫修改
70 */
71 ts.commit();
72 //session會拿session中的所有的持久化對象和
73 session.close();
74
75 System.out.println(user);
76 }
77 }
View Code
hibernate的一級緩存：
1 /**
2 * @author nunu
3 * 一級緩存
4 */
5 public class TestHibernateSession {
6
7 /**
8 * 查詢結果會放入session中，從session中獲取結果不需要查詢語句
9 */
10 @Test
11 public void sessionQuery() {
12 SessionFactory sf = H3Util.getSessionFactory();
13 Session session = sf.openSession();
14
15 //默認所有查詢，都會將結果存入到一級緩存（session）
16 //HQL、QBC、原生SQL查找：每次都會發送新sql,不會去session中獲取
17 Query query = session.createQuery("from User where userId = '4028810d57c20db20157c20db58c000e'");
18 User user = (User)query.uniqueResult();
19
20 Query query1 = session.createQuery("from User where userId = 'ff80808157c72cbe0157c72cc1540000'");
21 User user1 = (User)query1.uniqueResult();
22 System.out.println("0"+user);
23 System.out.println("1"+user1);
24 User user2 = (User)session.get(User.class,"4028810d57c20db20157c20db58c000e");
25 //user2的獲取不會發出查詢語句
26 System.out.println("2"+user2);
27 session.close();
28 }
29
30
31 /**
32 * 不發出update方法，修改session中結果是，再次獲取的該值是修改過的結果
33 *
34 * 先去session緩存（一級緩存）查詢看有沒對應的對象
35 * 如果沒有就會立即（無論有沒有使用到該對象）發生sql語句去數據庫查找，
36 * 查詢到之後會將查詢結果再存入到session緩存（一級緩存中）
37 */
38 @Test
39 public void testSessionUpdate() {
40 SessionFactory sf = H3Util.getSessionFactory();
41 Session session = sf.openSession();
42 User user = (User)session.get(User.class,"4028810d57c20db20157c20db5920013");
43
44 user.setUsername("admin");
45
46 //不會發送sql語句：
47 //User user1 = (User)session.get(User.class,"4028810d57c20db20157c20db5920013");
48 //System.out.println(user1);
49 //獲取到是最新的對象信息
50 //System.out.println(user1.getUsername());
51
52 session.close();
53 }
54
55
56 /**
57 * 懶加載
58 * org.hibernate.LazyInitializationException: could not initialize proxy - no Session
59 * 先去session緩存（一級緩存）查詢看有沒對應的對象
60 * 如果沒有,再看程序中有沒有使用改對象到除OID之外的屬性，如果只是使用了OID它不會發送任何sql語句
61 * 但是如果使用除OID之外的屬性，此時（使用之前）才會發送sql語句查詢
62 */
63 @Test
64 public void testLoad() {
65 SessionFactory sf = H3Util.getSessionFactory();
66 Session session = sf.openSession();
67 User user1 = (User) session.load(User.class, "4028810d57c20db20157c20db5920013");
68 User user2 = (User) session.load(User.class, "ff80808157c72cbe0157c72cc1540000");
69 System.out.println("--------------");
70
71 System.out.println(user1);
72 System.out.println(user2);
73
74 session.close();
75
76 //發送：sql
77 //System.out.println(user.getUsername());
78
79 //System.out.println(user1.getUsername());
80 }
81 }
View Code
hibernate的模糊查詢、單條記錄查詢、分頁查詢、、等單表基本查詢
1 public class TestQuery {
2 @Test
3 public void list() {
4 SessionFactory sessionFactory = H3Util.getSessionFactory();
5 Session session = sessionFactory.openSession();
6 String hql = "from User";
7 Query query = session.createQuery(hql);
8 @SuppressWarnings("unchecked")
9 List<User> uList = query.list();
10 for (User user : uList) {
11 System.out.println(user);
12 }
13 session.close();
14 }
15
16 /**
17 * 模糊查詢
18 */
19 @Test
20 public void list1() {
21 SessionFactory sessionFactory = H3Util.getSessionFactory();
22 Session session = sessionFactory.openSession();
23 String hql = "from User as u where u.username like :username";
24 Query query = session.createQuery(hql);
25 query.setString("username", "%test1%");
26 @SuppressWarnings("unchecked")
27 List<User> uList = query.list();
28 for (User user : uList) {
29 System.out.println(user);
30 }
31 session.close();
32 }
33
34 /**
35 * 模糊查詢
36 */
37 @Test
38 public void list2() {
39 SessionFactory sessionFactory = H3Util.getSessionFactory();
40 Session session = sessionFactory.openSession();
41 String hql = "from User as u where u.username like ?";
42 Query query = session.createQuery(hql);
43 query.setString(0, "%test1%");
44 @SuppressWarnings("unchecked")
45 List<User> uList = query.list();
46 for (User user : uList) {
47 System.out.println(user);
48 }
49 session.close();
50 }
51
52 /**
53 * 單個記錄查詢
54 */
55 @Test
56 public void uniqueResult() {
57 SessionFactory sessionFactory = H3Util.getSessionFactory();
58 Session session = sessionFactory.openSession();
59 String hql = "from User where userId = '4028810d57c20db20157c20db58c000a'";
60 Query query = session.createQuery(hql);
61 User u = (User) query.uniqueResult();
62 System.out.println(u);
63 session.close();
64 }
65 //findUsername
66 @Test
67 public void findUsername() {
68 SessionFactory sessionFactory = H3Util.getSessionFactory();
69 Session session = sessionFactory.openSession();
70 String hql = "select username from User";
71 Query query = session.createQuery(hql);
72 @SuppressWarnings("unchecked")
73 List<String> names = query.list();
74 for (String string : names) {
75 System.out.println("==="+string);
76 }
77 session.close();
78 }
79
80
81 @Test//查詢多個屬性（投影）
82 public void findUsernameAndId(){
83 SessionFactory sf = H3Util.getSessionFactory();
84 Session session = sf.openSession();
85
86 //sql：select username,sex from t_user
87 //String hql = "select sex,username from User where userId = '4028408157bbe02f0157bbe030820000' ";
88 //Query query = session.createQuery(hql);
89
90 //返回值至多有一個：多了就會報異常 org.hibernate.NonUniqueResultException: query did not return a unique result: 2
91 /*Object[] obj = (Object[]) query.uniqueResult();
92
93 System.out.println("sex"+obj[0]);
94 System.out.println("username"+obj[1]);*/
95
96 //將查詢結果封裝到對象中:提供大量的構造方法
97 String hql = "select new User(userId,username) from User where userId = '4028810d57c20db20157c20db58b0005' ";
98 Query query = session.createQuery(hql);
99 User user = (User)query.uniqueResult();
100
101 System.out.println(user);
102 }
103
104 /**
105 * 分頁查詢
106 */
107 @Test
108 public void findByPage() {
109 SessionFactory sf = H3Util.getSessionFactory();
110 Session session = sf.openSession();
111
112
113 int currentPage = 2;
114 int pageSize = 3;
115 String hql = "from User";
116 Query query = session.createQuery(hql);
117 query.setFirstResult((currentPage-1)*pageSize);
118 query.setMaxResults(pageSize);
119 @SuppressWarnings("unchecked")
120 List<User> uList = query.list();
121 for (User user : uList) {
122 System.out.println(user);
123 }
124 session.close();
125 }
126
127
128 @Test//固定條件查詢：查詢username = 李四
129 public void findByUsername(){
130 SessionFactory sf = H3Util.getSessionFactory();
131 Session session = sf.openSession();
132 String hql = "from User where username = '李四'";
133 Query query = session.createQuery(hql);
134 @SuppressWarnings("unchecked")
135 List<User> list = query.list();
136 for (User user : list) {
137 System.out.println(user);
138 }
139 }
140 @Test//可變參條件查詢：查詢username = 李四
141 public void findByUsername1(){
142 String username = "李四";
143 int sex = 1;
144 float salary = 10000.0f;
145 SessionFactory sf = H3Util.getSessionFactory();
146 Session session = sf.openSession();
147 //String hql = "from User where sex = ? and username = ? and salary = ?";
148 //Query query = session.createQuery(hql);
149 //為？設置具體數值
150 //只能使用索引方式設置值：此形式參數傳遞索引，靈活度太差，不推薦使用
151 //query.setString(0, username);
152 //query.setInteger(1, sex);
153 //query.setFloat(2, salary);
154
155
156 //使用:別名 占位符形式
157 //使用屬性名（占位符）方式設置值（推薦）：名稱和：後面的一致
158 String hql = "from User where sex = :sex and username = :username and salary = :salary";
159 Query query = session.createQuery(hql);
160 query.setString("username", username);
161 query.setInteger("sex", sex);
162 //query.setFloat("salary", salary);
163 query.setParameter("salary", salary);//如果不確定類型可以使用該方式，不推薦使用
164
165 @SuppressWarnings("unchecked")
166 List<User> list = query.list();
167 for (User user : list) {
168 System.out.println(user);
169 }
170 }
171
172 @Test//統計記錄個數
173 public void findCount(){
174 SessionFactory sf = H3Util.getSessionFactory();
175 Session session = sf.openSession();
176 String hql = "select count(*) from User";
177 Query query = session.createQuery(hql);
178
179 Long count = (Long) query.uniqueResult();
180 System.out.println(count);
181 }
182
183 @Test//最小值
184 public void findMin(){
185 SessionFactory sf = H3Util.getSessionFactory();
186 Session session = sf.openSession();
187 //返回值：和字段類型一致
188 String hql = "select min(salary) from User";
189 Query query = session.createQuery(hql);
190
191 Float min = (Float) query.uniqueResult();
192 System.out.println(min);
193 }
194
195 @Test//求和
196 public void findSum(){
197 SessionFactory sf = H3Util.getSessionFactory();
198 Session session = sf.openSession();
199 //返回值：整形Long/小數Double
200 String hql = "select sum(salary) from User";
201 Query query = session.createQuery(hql);
202
203 Double sum = (Double) query.uniqueResult();
204 System.out.println(sum);
205 }
206 @Test//求平均值
207 public void findAvg(){
208 SessionFactory sf = H3Util.getSessionFactory();
209 Session session = sf.openSession();
210 //返回值：Double
211 String hql = "select avg(salary) from User";
212 Query query = session.createQuery(hql);
213
214 Double avg = (Double) query.uniqueResult();
215 System.out.println(avg);
216 }
217
218 @Test//求分組查找
219 public void findGroup(){
220 SessionFactory sf = H3Util.getSessionFactory();
221 Session session = sf.openSession();
222 String hql = "select sex, count(*) from User group by sex";
223 Query query = session.createQuery(hql);
224 @SuppressWarnings("unchecked")
225 List<Object[]> list = query.list();
226 for (int i=0;i<list.size();i++) {
227 System.out.println(list.get(i)[0]+":"+list.get(i)[1]);
228 }
229 }
230 @Test//求排序
231 public void findOrder(){
232 SessionFactory sf = H3Util.getSessionFactory();
233 Session session = sf.openSession();
234 String hql = "from User order by salary asc,sex asc";
235 Query query = session.createQuery(hql);
236 @SuppressWarnings("unchecked")
237 List<User> list = query.list();
238 for (User user : list) {
239 System.out.println(user);
240 }
241 }
242 @Test//求排序
243 public void findOrder1(){
244 SessionFactory sf = H3Util.getSessionFactory();
245 Session session = sf.openSession();
246 Query query = session.getNamedQuery("findOrder");
247 @SuppressWarnings("unchecked")
248 List<User> list = query.list();
249 for (User user : list) {
250 System.out.println(user);
251 }
252 }
253 }
View Code
hibernate的QBC：query by criteria
1 /**
2 * @author nunu
3 * QBC：query by criteria
4 */
5 public class TestCriteria {
6
7 /**
8 * criteria 普通查詢
9 */
10 @Test
11 public void list(){
12 SessionFactory sf = H3Util.getSessionFactory();
13 Session session = sf.openSession();
14 Criteria criteria = session.createCriteria(User.class);
15 @SuppressWarnings("unchecked")
16 List<User> uList = criteria.list();
17 for (User user : uList) {
18 System.out.println(user);
19 }
20 }
21
22 /**
23 * 查詢用戶名
24 */
25 @Test
26 public void findUsername(){
27 SessionFactory sf = H3Util.getSessionFactory();
28 Session session = sf.openSession();
29 //select username from User
30 Criteria criteria = session.createCriteria(User.class);
31 //准備投影（屬性）
32 Property prop = Property.forName("username");
33 //設置投影（屬性）
34 criteria.setProjection(prop);
35
36 @SuppressWarnings("unchecked")
37 List<String> usernames = criteria.list();
38 for (String name : usernames) {
39 System.out.println(name);
40 }
41 }
42
43
44 /**
45 * 查詢用戶名和性別
46 */
47 @Test
48 public void findUsernameSex(){
49 SessionFactory sf = H3Util.getSessionFactory();
50 Session session = sf.openSession();
51 //select username from User
52 Criteria criteria = session.createCriteria(User.class);
53 //准備投影（屬性）
54 Property prop1 = Property.forName("username");
55 Property prop2 = Property.forName("sex");
56
57 //獲取投影集合
58 ProjectionList pList = Projections.projectionList();
59 pList.add(prop1);
60 pList.add(prop2);
61 //設置投影（屬性）
62 criteria.setProjection(pList);
63
64 @SuppressWarnings("unchecked")
65 List<Object[]> usernames = criteria.list();
66 for (int i = 0; i < usernames.size(); i++) {
67 System.out.println(usernames.get(i)[0]+":"+usernames.get(i)[1]);;
68 }
69 }
70
71 /**
72 * 模糊查詢
73 */
74 @Test
75 public void findByName(){
76 SessionFactory sf = H3Util.getSessionFactory();
77 Session session = sf.openSession();
78 //select username from User where username = :name
79 Criteria criteria = session.createCriteria(User.class);
80 //添加條件
81 //criteria.add(Restrictions.eq("username", "李四"));
82 criteria.add(Restrictions.like("username", "%test1%"));
83
84 @SuppressWarnings("unchecked")
85 List<User> list = criteria.list();
86 for (User user : list) {
87 System.out.println(user);
88 }
89 }
90 @Test
91 public void findGroup(){
92 SessionFactory sf = H3Util.getSessionFactory();
93 Session session = sf.openSession();
94 //select username from User group by sex
95 Criteria criteria = session.createCriteria(User.class);
96
97 Projection p1 = Projections.groupProperty("sex");
98 Projection p2 = Projections.rowCount();//count(*)
99
100 ProjectionList pList = Projections.projectionList();
101 pList.add(p1);
102 pList.add(p2);
103 //分組
104 criteria.setProjection(pList);
105 @SuppressWarnings("unchecked")
106 List<Object[]> list = criteria.list();
107
108 for (int i = 0; i < list.size(); i++) {
109 System.out.println(list.get(i)[0]+":"+list.get(i)[1]);
110 }
111 }
112 }
View Code
hibernate 中使用SQL語句查詢
1 /**
2 * @author nunu
3 * hibernate 中使用SQL語句查詢
4 */
5 public class TestSQLQuery {
6
7 @Test
8 public void testList() {
9 SessionFactory sf = H3Util.getSessionFactory();
10 Session session = sf.openSession();
11 String sql = "select * from t_user";
12 SQLQuery sqlQuery = session.createSQLQuery(sql);
13 @SuppressWarnings("unchecked")
14 List<Object[]> uList = sqlQuery.list();
15 for (Object[] user : uList) {
16 for (int i = 0; i < user.length; i++) {
17 System.out.println(user[i]);
18 }
19 }
20 }
21
22
23 @Test
24 public void testList1() {
25 SessionFactory sf = H3Util.getSessionFactory();
26 Session session = sf.openSession();
27 String sql = "select * from t_user";
28 SQLQuery sqlQuery = session.createSQLQuery(sql);
29 //告訴系統如何去封裝對象
30 sqlQuery.addEntity(User.class);
31 @SuppressWarnings("unchecked")
32 List<User> uList = sqlQuery.list();
33 for (User user : uList) {
34 System.out.println(user);
35 }
36 }
37
38 /**
39 * 指明對象
40 */
41 @Test
42 public void testList2() {
43 SessionFactory sf = H3Util.getSessionFactory();
44 Session session = sf.openSession();
45 String sql = "select u.* from t_user u";
46 SQLQuery sqlQuery = session.createSQLQuery(sql);
47 //告訴系統如何去封裝對象
48 sqlQuery.addEntity("u",User.class);
49 @SuppressWarnings("unchecked")
50 List<User> uList = sqlQuery.list();
51 for (User user : uList) {
52 System.out.println(user);
53 }
54 }
55 }
View Code
