Skip to main content
Hint

This article is generated by AI translation.

Type Mapping and Handlers

When a Java int maps to a database int, three aspects matter:

  • ➊ Java type used by the property
  • ➋ JDBC type of the column
  • ➌ TypeHandler for reading/writing
@Table
public class Users {
    @Column(➋ jdbcType = java.sql.Types.TINYINT, ➌ typeHandler = IntegerTypeHandler.class)
    private ➊ Integer id;
}
info

In most cases you can ignore jdbcType and typeHandler; the framework selects them from the Java type.

Handle abstract types​

@Table
public class Users {
    @Column(specialJavaType = Integer.class)
    private Number counter;
}

Handle enums​

@Table
public class Users {
    @Column
    private UserTypeEnum type; // Automatically supported; no extra work
}

Handle JSON serialization​

Bind JSON serializer via @Column
@Table
public class Users {
    @Column(typeHandler = net.hasor.dbvisitor.types.handler.json.JsonTypeHandler.class)
    private UserExtInfo moreInfo; // Field is serialized/deserialized as JSON
}
Set serializer for a type via @BindTypeHandler
@BindTypeHandler(net.hasor.dbvisitor.types.handler.json.JsonTypeHandler.class)
public class UserExtInfo {
    ...
}

@Table
public class Users {
    private UserExtInfo moreInfo;
}

Use a custom TypeHandler​

public class User {
    @Column(typeHandler = MyDateTypeHandler.class)
    private String myTime;
}