mybatis日志能正常打印出正確sql執行語句；數據庫有內容；卻查詢不出來

首先是返回值封裝為List的時候獲取不到值；為單個對象的時候正常

這個是要執行的調試語句；發現執行完畢控制台如下；sql正確；對象和數據庫關系映射也正確；

//執行語句
        List<Object> list = sqlSession.selectList("test.getUserByName", "五");
        for (Object user : list) {
            System.out.println("user"+user);
        }
執行完畢出現下面的問題
DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.slf4j.Slf4jImpl' adapter.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
DEBUG [main] - Opening JDBC Connection
DEBUG [main] - Created connection 733957003.
DEBUG [main] - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@2bbf4b8b]
DEBUG [main] - ooo Using Connection [com.mysql.jdbc.JDBC4Connection@2bbf4b8b]
DEBUG [main] - ==> Preparing: select * from user where username LIKE '%五%' 
DEBUG [main] - ==> Parameters: 
DEBUG [main] - <== Total: 0
DEBUG [main] - Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@2bbf4b8b]
DEBUG [main] - Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@2bbf4b8b]
DEBUG [main] - Returned connection 733957003 to pool.

 

 

然后寫了個最簡單的demo發現仍然出現問題；檢查到最后發現是數據源的url編碼問題；沒有設置為Utf-8；具體原理還沒有找到；希望各位可以解讀下原理

jdbc:mysql://localhost:3306/demo?characterEncoding=utf-8" 

更改之后就好了；記錄一下，這個錯誤浪費了半天的時間