public class EnsemblLookup extends EnsemblRestClient
{
private static final String SPECIES = "species";
- private static final String OBJECT_TYPE_TRANSLATION = "Translation";
- private static final String PARENT = "Parent";
- private static final String OBJECT_TYPE_TRANSCRIPT = "Transcript";
- private static final String ID = "id";
- private static final String OBJECT_TYPE_GENE = "Gene";
- private static final String OBJECT_TYPE = "object_type";
/**
* keep track of last identifier retrieved to break loops
*/
public String getGeneId(String identifier)
{
- return parseGeneId(getResult(identifier, null));
+ return getGeneId(identifier, null);
+ }
+
+ /**
+ * Returns the gene id related to the given identifier (which may be for a
+ * gene, transcript or protein)
+ *
+ * @param identifier
+ * @param objectType
+ * @return
+ */
+ public String getGeneId(String identifier, String objectType)
+ {
+ List<String> ids = Arrays.asList(new String[] { identifier });
+
+ BufferedReader br = null;
+ try
+ {
+ URL url = getUrl(identifier, objectType);
+ if (url != null)
+ {
+ br = getHttpResponse(url, ids);
+ }
+ return br == null ? null : parseResponse(br);
+ } catch (IOException e)
+ {
+ // ignore
+ return null;
+ } finally
+ {
+ if (br != null)
+ {
+ try
+ {
+ br.close();
+ } catch (IOException e)
+ {
+ // ignore
+ }
+ }
+ }
+ }
+
+ /**
+ * Parses the JSON response and returns the gene identifier, or null if not
+ * found. If the returned object_type is Gene, returns the id, if Transcript
+ * returns the Parent. If it is Translation (peptide identifier), then the
+ * Parent is the transcript identifier, so we redo the search with this value.
+ *
+ * @param br
+ * @return
+ * @throws IOException
+ */
+ protected String parseResponse(BufferedReader br) throws IOException
+ {
+ String geneId = null;
+ JSONParser jp = new JSONParser();
+ try
+ {
+ JSONObject val = (JSONObject) jp.parse(br);
+ String type = val.get(OBJECT_TYPE).toString();
+ if (OBJECT_TYPE_GENE.equalsIgnoreCase(type))
+ {
+ // got the gene - just returns its id
+ geneId = val.get(JSON_ID).toString();
+ }
+ else if (OBJECT_TYPE_TRANSCRIPT.equalsIgnoreCase(type))
+ {
+ // got the transcript - return its (Gene) Parent
+ geneId = val.get(PARENT).toString();
+ }
+ else if (OBJECT_TYPE_TRANSLATION.equalsIgnoreCase(type))
+ {
+ // got the protein - get its Parent, restricted to type Transcript
+ String transcriptId = val.get(PARENT).toString();
+ geneId = getGeneId(transcriptId, OBJECT_TYPE_TRANSCRIPT);
+ }
+ } catch (ParseException e)
+ {
+ // ignore
+ }
+ return geneId;
}
/**