数据库类型和Java类型之间的关系：

DBC Type Java Type CHAR String VARCHAR String LONGVARCHAR String NUMERIC java.math.BigDecimal DECIMAL java.math.BigDecimal BIT boolean BOOLEAN boolean TINYINT byte SMALLINT short INTEGER int BIGINT long REAL float FLOAT double DOUBLE double BINARY byte [] VARBINARY byte [] LONGVARBINARY byte [] DATE java.sql.Date TIME java.sql.Time TIMESTAMP java.sql. Timestamp CLOB Clob BLOB Blob ARRAY Array DISTINCT mapping of underlying type STRUCT Struct REF Ref