[
https://issues.apache.org/jira/browse/AVRO-680?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14098976#comment-14098976
]
Sachin Goyal commented on AVRO-680:
-----------------------------------
Consider the following code in GenericData#toString()
{code}
} else if (isArray(datum)) {
Collection<?> array = (Collection<?>)datum;
buffer.append("[");
long last = array.size()-1;
int i = 0;
for (Object element : array) {
toString(element, buffer);
if (i++ < last)
buffer.append(", ");
}
buffer.append("]");
} else if (isMap(datum)) {
buffer.append("{");
int count = 0;
@SuppressWarnings(value="unchecked")
Map<Object,Object> map = (Map<Object,Object>)datum;
for (Map.Entry<Object,Object> entry : map.entrySet()) {
toString(entry.getKey(), buffer);
buffer.append(": ");
toString(entry.getValue(), buffer);
if (++count < map.size())
buffer.append(", ");
}
buffer.append("}");
}
{code}
If we make isMap return false and isArray return true, then the above code
would fail while typecasting Map to a Collection. Thus, one of the callers of
isMap/isArray would need to change to support non-string maps if we make the
suggested change.
Same holds true for #validate():
{code}
case ARRAY:
if (!(isArray(datum))) return false;
for (Object element : (Collection<?>)datum)
if (!validate(schema.getElementType(), element))
return false;
return true;
case MAP:
if (!(isMap(datum))) return false;
@SuppressWarnings(value="unchecked")
Map<Object,Object> map = (Map<Object,Object>)datum;
for (Map.Entry<Object,Object> entry : map.entrySet())
if (!validate(schema.getValueType(), entry.getValue()))
return false;
return true;
{code}
Ditto, for #induce():
{code}
} else if (isArray(datum)) {
Schema elementType = null;
for (Object element : (Collection<?>)datum) {
{code}
getSchemaName() is being called from resolveUnion() only.
So with current patch, it does not need to change.
#instanceOf() don't seem to be used.
So I am not sure if we need to count it.
So IMHO, it should be safe to use the current patch.
If you still think otherwise, I will change all the above methods along with
isMap and isArray.
> Allow for non-string keys
> -------------------------
>
> Key: AVRO-680
> URL: https://issues.apache.org/jira/browse/AVRO-680
> Project: Avro
> Issue Type: Improvement
> Affects Versions: 1.7.6, 1.7.7
> Reporter: Jeremy Hanna
> Attachments: AVRO-680.patch, isMap_Call_Hierarchy.png,
> non_string_map_keys.zip, non_string_map_keys2.zip, non_string_map_keys3.zip,
> non_string_map_keys4.patch, non_string_map_keys5.patch,
> non_string_map_keys6.patch
>
>
> Based on an email thread back in April, Doug Cutting proposed a possible
> solution for having non-string keys:
> Stu Hood wrote:
> > I can understand the reasoning behind AVRO-9, but now I need to look for an
> > alternative to a 'map' that will allow me to store an association of bytes
> > keys to values.
> A map of Foo has the same binary format as an array of records, each
> with a string field and a Foo field. So an application can use an array
> schema similar to this to represent map-like structures with, e.g.,
> non-string keys.
> Perhaps we could establish standard properties that indicate that a
> given array of records should be represented in a map-like way if
> possible? E.g.,:
> {"type": "array", "isMap": true, "items": {"type":"record", ...}}
> Doug
--
This message was sent by Atlassian JIRA
(v6.2#6252)
