com.pixelmed.query

Interface QueryResponseGenerator

public interface QueryResponseGenerator

This interface abstracts the communication between a query (C-FIND) server that implements the network service, and the source of information with which to respond to the query.

Typically, the server, which has been supplied a factory to generate instances of a class that implements this interface, calls the methods with the following pattern:

        ... receive C-FIND request from the network into AttributeList identifier ...
        QueryResponseGenerator queryResponseGenerator = queryResponseGeneratorFactory.newInstance();
        queryResponseGenerator.performQuery(affectedSOPClassUID,identifier,false);
        AttributeList responseIdentifierList;
        while ((responseIdentifierList = queryResponseGenerator.next()) != null) {
                ... send response in responseIdentifierList over the network ...
        }
        queryResponseGenerator.close();

See Also:

QueryResponseGeneratorFactory

Method Summary

Modifier and Type	Method and Description
boolean	allOptionalKeysSuppliedWereSupported() Determine information needed to qualify pending response statuses.
void	close() Clean up after the query has completed.
java.lang.String	getErrorComment() Get any error comment in the case of an error status.
AttributeTagAttribute	getOffendingElement() Get the offending element in the case of an error status.
int	getStatus() Get a status suitable for the C-FIND response.
AttributeList	next() Get the next query response.
void	performQuery(java.lang.String querySOPClassUID, AttributeList queryIdentifier, boolean relational) Perform the query whose results will be returned by the next() method.

Method Detail

allOptionalKeysSuppliedWereSupported

boolean allOptionalKeysSuppliedWereSupported()

Determine information needed to qualify pending response statuses.

Returns:

false if any of the keys in the queryIdentifier were not supported as matching or return keys by the model

close

void close()

Clean up after the query has completed.

Typically, will discarded cached information, close any database connections, etc.

getErrorComment

java.lang.String getErrorComment()

Get any error comment in the case of an error status.

Returns:

the error comment, or null if none

getOffendingElement

AttributeTagAttribute getOffendingElement()

Get the offending element in the case of an error status.

Returns:

the offending element

getStatus

int getStatus()

Get a status suitable for the C-FIND response.

Returns:

the retrieve status

next

AttributeList next()

Get the next query response.

Returns:

the next query response as a list of DICOM attributes suitable for a C-FIND response dataset

performQuery

void performQuery(java.lang.String querySOPClassUID,
                  AttributeList queryIdentifier,
                  boolean relational)

Perform the query whose results will be returned by the next() method.

Whether or not the query is actually performed during this call, or the parameters cached and perform on the first next() call, or indeed next() represents a dynamic query, is unspecified and up to the implementor of the interface.

Parameters:

querySOPClassUID - defines the information model to use (e.g., study root, patient root)

queryIdentifier - the query itself, as received in the C-FIND dataset

relational - whether or not to perform relational queries (as determined by extended negotiation)