Want Mybatis to insert booleans as Y,N, not 0,1 - mybatis

Question

I'm writing a class instance to a MySQL DB using MyBatis
// I have no control over how this java class is laid out -.-
class Hello {
boolean isFriendly
}
my MyBatis Mapper looks like this
<insert id="doHello" parameterType="Hello">
insert into hello_table (
is_friendly --this is a varchar(1) btw
)
values (
#{isFriendly}
)
</insert>
The problem is it inserts the values into the DB as 0 or 1, but I need to have it as 'N' or 'Y'
and I don't have the choice of modifying the java
I'm trying to keep my code as minimal as possible and ideally would like to add stuff into the Mybatis Mapper
I tried things like
#{isFriendly,jdbcType=Boolean}
but it didn't work

Answer 1

MyBatis typeHandler is a proper way to do it.
You could implement a type handler and then use it in any sql statement:
#{isFriendly, typeHandler=YesNoBooleanTypeHandler}
For the details see MyBatis Java Boolean to Sql enum

Answer 2

Modify your insert statement
insert into hello_table (
is_friendly
)values (${isFriendly=="0"?"'N'":"'Y'"})

Answer 3

create handler and add it in Mybatis configuration
create handler:
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
#MappedTypes(Boolean.class)
#MappedJdbcTypes(JdbcType.CHAR)
public class BooleanStringTypeHandler extends BaseTypeHandler {
#Override
public void setNonNullParameter(PreparedStatement preparedStatement, int i, Boolean aBoolean, JdbcType jdbcType) throws SQLException {
preparedStatement.setString(i, aBoolean ? "Y" : "N");
}
#Override
public Boolean getNullableResult(ResultSet resultSet, String s) throws SQLException {
return getBoolean(resultSet.getString(s));
}
#Override
public Boolean getNullableResult(ResultSet resultSet, int i) throws SQLException {
return getBoolean(resultSet.getString(i));
}
#Override
public Boolean getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
return getBoolean(callableStatement.getString(i));
}
private Boolean getBoolean(String s) {
return "Y".equalsIgnoreCase(s);
}
}
add it in your Mybatis configuration:
<typeHandlers>
<typeHandler jdbcType="CHAR" javaType="java.lang.Boolean" handler="crm.data.trade.utils.BooleanStringTypeHandler"/>
</typeHandlers>