Error: java.lang.AbstractMethodError: Method oracle/jdbc/driver/OracleResultSetImpl.getNString(Ljava/lang/String;)Ljava/lang/String; is abstract,
Problem: The jdbcType definition in the mapper.xml code is not consistent with the one in the database and the entity class.
Solution 1: violent solution, directly remove the jdbcType in the resultMap defined in mapper.xml , do not specify the data type
Solution 2: Check the data types in the entity class, database and resultMap one by one, all three should be consistent
Attachment: Default mapping of MySQL data types, JDBC data types, Java data types
| MySQL DATA TYPE | JDBC TYPE(getColumnTypeName) | The default JAVA type returned(getColumnClassName) |
|---|---|---|
BIT(1) (new in MySQL-5.0) |
BIT |
java.lang.Boolean |
BIT( > 1) (new in MySQL-5.0) |
BIT |
byte[] |
TINYINT |
TINYINT |
java.lang.Boolean if the configuration property tinyInt1isBit is set to true (the default) and the storage size is 1, or java.lang.Integer if not. |
BOOL, BOOLEAN |
TINYINT |
See TINYINT, above as these are aliases for TINYINT(1), currently. |
SMALLINT[(M)] [UNSIGNED] |
SMALLINT [UNSIGNED] |
java.lang.Integer (regardless of whether it is UNSIGNED or not) |
MEDIUMINT[(M)] [UNSIGNED] |
MEDIUMINT [UNSIGNED] |
java.lang.Integer (regardless of whether it is UNSIGNED or not) |
INT,INTEGER[(M)] [UNSIGNED] |
INTEGER [UNSIGNED] |
java.lang.Integer, if UNSIGNED java.lang.Long |
BIGINT[(M)] [UNSIGNED] |
BIGINT [UNSIGNED] |
java.lang.Long, if UNSIGNED java.math.BigInteger |
FLOAT[(M,D)] |
FLOAT |
java.lang.Float |
DOUBLE[(M,B)] |
DOUBLE |
java.lang.Double |
DECIMAL[(M[,D])] |
DECIMAL |
java.math.BigDecimal |
DATE |
DATE |
java.sql.Date |
DATETIME |
DATETIME |
java.sql.Timestamp |
TIMESTAMP[(M)] |
TIMESTAMP |
java.sql.Timestamp |
TIME |
TIME |
java.sql.Time |
YEAR[(2|4)] |
YEAR |
If yearIsDateType configuration property is set to false, then the returned object type is java.sql.Short. If set to true (the default), then the returned object is of type java.sql.Datewith the date set to January 1st, at midnight. |
CHAR(M) |
CHAR |
java.lang.String (unless the character set for the column is BINARY, then byte[] is returned. |
VARCHAR(M) [BINARY] |
VARCHAR |
java.lang.String (unless the character set for the column is BINARY, then byte[] is returned. |
BINARY(M) |
BINARY |
byte[] |
VARBINARY(M) |
VARBINARY |
byte[] |
TINYBLOB |
TINYBLOB |
byte[] |
TINYTEXT |
VARCHAR |
java.lang.String |
BLOB |
BLOB |
byte[] |
TEXT |
VARCHAR |
java.lang.String |
MEDIUMBLOB |
MEDIUMBLOB |
byte[] |
MEDIUMTEXT |
VARCHAR |
java.lang.String |
LONGBLOB |
LONGBLOB |
byte[] |
LONGTEXT |
VARCHAR |
java.lang.String |
ENUM('value1','value2',...) |
CHAR |
java.lang.String |
SET('value1','value2',...) |
CHAR |
java.lang.String |
MySQL JDBC allows conversions between different data types: the conversion table is as follows
| MySQL DATA TYPE | JAVA types that can be converted |
|---|---|
CHAR, VARCHAR, BLOB, TEXT, ENUM, and SET |
java.lang.String, java.io.InputStream, java.io.Reader, java.sql.Blob, java.sql.Clob |
FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT, SMALLINT, MEDIUMINT, INTEGER, BIGINT |
java.lang.String, java.lang.Short, java.lang.Integer, java.lang.Long, java.lang.Double, java.math.BigDecimal |
DATE, TIME, DATETIME, TIMESTAMP |
java.lang.String, java.sql.Date, java.sql.Timestamp |