Retrieve a specific field using Java API

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1

Hi,

I'm trying to retrieve a specific field of document using Java API.
I am using the following code:

GetResponse response = client.prepareGet(index, type,
id).execute().actionGet();
Map<String, GetField> fieldMap = response.fields();
GetField field = fieldMap.get("title");
return (String)field.getValue();

which fails, because "title" field has null value.
But if try "response.exists()", it gives me "true".

Strangely, when I try the same thing with the following command:
"curl -XGET 'http://localhost:9200/news/type1/12345?fields=title'"
I get the result I want.

So what is the difference here?
I chose not to store json source when indexing the document. Is this
the cause of the problem?

Ed

2

By default, the source is returned. Use any of the source methods on the
GetResponse. If you want to get just a specific field, you can ask for it
in the get request (and then, _source will not be returned unless you ask
for it explicitly as well).

On Sun, Jan 15, 2012 at 6:13 PM, mp2893 mp2893@gmail.com wrote:

Hi,

I'm trying to retrieve a specific field of document using Java API.
I am using the following code:

GetResponse response = client.prepareGet(index, type,
id).execute().actionGet();
Map<String, GetField> fieldMap = response.fields();
GetField field = fieldMap.get("title");
return (String)field.getValue();

which fails, because "title" field has null value.
But if try "response.exists()", it gives me "true".

Strangely, when I try the same thing with the following command:
"curl -XGET 'http://localhost:9200/news/type1/12345?fields=title'"
I get the result I want.

So what is the difference here?
I chose not to store json source when indexing the document. Is this
the cause of the problem?

Ed

3

Thanks for the info.
I tried the following code:
"GetResponse response = client.prepareGet(index, type,
id).setFields("title").execute().actionGet();"
and it returned with the "title" object.
The "setFields" option is what did the trick.
Thanks again.

Ed

2012/1/16 Shay Banon kimchy@gmail.com

By default, the source is returned. Use any of the source methods on the
GetResponse. If you want to get just a specific field, you can ask for it
in the get request (and then, _source will not be returned unless you ask
for it explicitly as well).

On Sun, Jan 15, 2012 at 6:13 PM, mp2893 mp2893@gmail.com wrote:

Hi,

I'm trying to retrieve a specific field of document using Java API.
I am using the following code:

GetResponse response = client.prepareGet(index, type,
id).execute().actionGet();
Map<String, GetField> fieldMap = response.fields();
GetField field = fieldMap.get("title");
return (String)field.getValue();

which fails, because "title" field has null value.
But if try "response.exists()", it gives me "true".

Strangely, when I try the same thing with the following command:
"curl -XGET 'http://localhost:9200/news/type1/12345?fields=title'"
I get the result I want.

So what is the difference here?
I chose not to store json source when indexing the document. Is this
the cause of the problem?

Ed

4

what about when you want multiple fields. I tried a comma delimited list
and it assumed the entire string was the field name. I tried calling
setFields for each field and it only takes the last field. I tried setting
setField with a String[] but that too failed. Is there something I'm
missing here?

5

How are you indexing it? Is it a field with multiple values (an array in json)? If so, you will get an array back.

On Wednesday, February 22, 2012 at 8:02 PM, Wes Plunk wrote:

what about when you want multiple fields. I tried a comma delimited list and it assumed the entire string was the field name. I tried calling setFields for each field and it only takes the last field. I tried setting setField with a String but that too failed. Is there something I'm missing here?

6

The setFields method accepts multiple strings as parameters:

GetResponse response = client.prepareGet(index, type, id).setFields("title",
"name","postDate").execute().actionGet();
String title = (String)response.field("title").getValue();
String name = (String)response.field("name").getValue();
String postDate = (String)response.field("postDate").getValue();

El miércoles, 22 de febrero de 2012 19:02:29 UTC+1, Wes Plunk escribió:

what about when you want multiple fields. I tried a comma delimited list
and it assumed the entire string was the field name. I tried calling
setFields for each field and it only takes the last field. I tried setting
setField with a String but that too failed. Is there something I'm
missing here?

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