@Autowired

private UserMapper userMapper;

@Test

public void testGetUserById() {

System.out.println("------------------------------1");

User user = userMapper.getUserById(1);

System.out.println("------------------------------2");

User user2 = userMapper.getUserById(1);

System.out.println("------------------------------3");

User user3 = userMapper.getUserById(1);

Assert.assertArrayEquals(new int[] { user.getId() }, new int[] { 1 });

}

------------------------------1

2017-04-11 08:57:50,655 DEBUG [SqlSessionUtils.java:97] Creating a new SqlSession

2017-04-11 08:57:50,656 DEBUG [SqlSessionUtils.java:148] SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@54144b42] was not registered for synchronization because synchronization is not active

2017-04-11 08:57:50,656 DEBUG [DataSourceUtils.java:110] Fetching JDBC Connection from DataSource

2017-04-11 08:57:50,657 DEBUG [SpringManagedTransaction.java:87] JDBC Connection [com.mysql.jdbc.JDBC4Connection@62d6b944] will not be managed by Spring

2017-04-11 08:57:50,657 DEBUG [BaseJdbcLogger.java:181] ==> Preparing: SELECT * FROM user WHERE id = ?

2017-04-11 08:57:50,657 DEBUG [BaseJdbcLogger.java:181] ==> Parameters: 1(Integer)

2017-04-11 08:57:50,661 DEBUG [BaseJdbcLogger.java:181] <== Total: 1

2017-04-11 08:57:50,661 DEBUG [SqlSessionUtils.java:191] Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@54144b42]

2017-04-11 08:57:50,661 DEBUG [DataSourceUtils.java:327] Returning JDBC Connection to DataSource

------------------------------2

2017-04-11 08:57:50,662 DEBUG [SqlSessionUtils.java:97] Creating a new SqlSession

2017-04-11 08:57:50,662 DEBUG [SqlSessionUtils.java:148] SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@54630f2f] was not registered for synchronization because synchronization is not active

2017-04-11 08:57:50,662 DEBUG [DataSourceUtils.java:110] Fetching JDBC Connection from DataSource

2017-04-11 08:57:50,662 DEBUG [SpringManagedTransaction.java:87] JDBC Connection [com.mysql.jdbc.JDBC4Connection@62d6b944] will not be managed by Spring

2017-04-11 08:57:50,663 DEBUG [BaseJdbcLogger.java:181] ==> Preparing: SELECT * FROM user WHERE id = ?

2017-04-11 08:57:50,664 DEBUG [BaseJdbcLogger.java:181] ==> Parameters: 1(Integer)

2017-04-11 08:57:50,666 DEBUG [BaseJdbcLogger.java:181] <== Total: 1

2017-04-11 08:57:50,667 DEBUG [SqlSessionUtils.java:191] Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@54630f2f]

2017-04-11 08:57:50,667 DEBUG [DataSourceUtils.java:327] Returning JDBC Connection to DataSource

------------------------------3

2017-04-11 08:57:50,667 DEBUG [SqlSessionUtils.java:97] Creating a new SqlSession

2017-04-11 08:57:50,668 DEBUG [SqlSessionUtils.java:148] SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@5e5f0b0] was not registered for synchronization because synchronization is not active

2017-04-11 08:57:50,668 DEBUG [DataSourceUtils.java:110] Fetching JDBC Connection from DataSource

2017-04-11 08:57:50,668 DEBUG [SpringManagedTransaction.java:87] JDBC Connection [com.mysql.jdbc.JDBC4Connection@62d6b944] will not be managed by Spring

2017-04-11 08:57:50,669 DEBUG [BaseJdbcLogger.java:181] ==> Preparing: SELECT * FROM user WHERE id = ?

2017-04-11 08:57:50,670 DEBUG [BaseJdbcLogger.java:181] ==> Parameters: 1(Integer)

2017-04-11 08:57:50,672 DEBUG [BaseJdbcLogger.java:181] <== Total: 1

2017-04-11 08:57:50,672 DEBUG [SqlSessionUtils.java:191] Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@5e5f0b0]

2017-04-11 08:57:50,672 DEBUG [DataSourceUtils.java:327] Returning JDBC Connection to DataSource

如上代码，多次调用userMapper.getUserById(1);方法，但每次都创建了一个sqlSession来处理请求，并不走一级缓存，这是为什么呢？要怎么处理才能让它走一级缓存呢？