How to use

JavaToSqlTypeConversionRules

in

org.apache.calcite.sql.type

  @Override
  public RelDataType toSql(RelDataType type) {
    if (type instanceof JavaType) {
      JavaType javaType = (JavaType) type;
      SqlTypeName sqlTypeName = JavaToSqlTypeConversionRules.instance().lookup(javaType.getJavaClass());
      if (sqlTypeName == null) {
        sqlTypeName = SqlTypeName.ANY;
      }
      return createTypeWithNullability(createSqlType(sqlTypeName), type.isNullable());
    }
    return super.toSql(type);
  }
}

 public SqlTypeName getSqlTypeName() {
  final SqlTypeName typeName =
    JavaToSqlTypeConversionRules.instance().lookup(clazz);
  if (typeName == null) {
   return SqlTypeName.OTHER;
  }
  return typeName;
 }
}

 public SqlTypeName getSqlTypeName() {
  final SqlTypeName typeName =
    JavaToSqlTypeConversionRules.instance().lookup(clazz);
  if (typeName == null) {
   return SqlTypeName.OTHER;
  }
  return typeName;
 }
}

  @Override
  public RelDataType toSql(RelDataType type) {
    if (type instanceof JavaType) {
      JavaType javaType = (JavaType) type;
      SqlTypeName sqlTypeName = JavaToSqlTypeConversionRules.instance().lookup(javaType.getJavaClass());
      if (sqlTypeName == null) {
        sqlTypeName = SqlTypeName.ANY;
      }
      return createTypeWithNullability(createSqlType(sqlTypeName), type.isNullable());
    }
    return super.toSql(type);
  }
}

 private static RelDataType convertToSql(final RelDataTypeFactory typeFactory,
   RelDataType type) {
  if (type instanceof RelRecordType) {
   return typeFactory.createStructType(
     Lists.transform(type.getFieldList(), a0 -> convertToSql(typeFactory, a0.getType())),
     type.getFieldNames());
  }
  if (type instanceof JavaType) {
   SqlTypeName typeName = JavaToSqlTypeConversionRules.instance().lookup(((JavaType) type).getJavaClass());
   // For unknown sql type names, return ANY sql type to make Calcite validation not fail.
   if (typeName == null) {
    typeName = SqlTypeName.ANY;
   }
   return typeFactory.createTypeWithNullability(
     typeFactory.createSqlType(typeName),
     type.isNullable());
  } else {
   return JavaTypeFactoryImpl.toSql(typeFactory, type);
  }
 }
}

 private static RelDataType convertToSql(final RelDataTypeFactory typeFactory,
   RelDataType type) {
  if (type instanceof RelRecordType) {
   return typeFactory.createStructType(
     Lists.transform(type.getFieldList(), a0 -> convertToSql(typeFactory, a0.getType())),
     type.getFieldNames());
  }
  if (type instanceof JavaType) {
   SqlTypeName typeName = JavaToSqlTypeConversionRules.instance().lookup(((JavaType) type).getJavaClass());
   // For unknown sql type names, return ANY sql type to make Calcite validation not fail.
   if (typeName == null) {
    typeName = SqlTypeName.ANY;
   }
   return typeFactory.createTypeWithNullability(
     typeFactory.createSqlType(typeName),
     type.isNullable());
  } else {
   return JavaTypeFactoryImpl.toSql(typeFactory, type);
  }
 }
}

 return createJavaType(Primitive.ofBox(clazz).boxClass);
if (JavaToSqlTypeConversionRules.instance().lookup(clazz) != null) {
 return createJavaType(clazz);
} else if (clazz.isArray()) {

 return createJavaType(Primitive.ofBox(clazz).boxClass);
if (JavaToSqlTypeConversionRules.instance().lookup(clazz) != null) {
 return createJavaType(clazz);
} else if (clazz.isArray()) {