package ca.uhn.hl7v2.conf.store;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.XMLReaderFactory;
import ca.uhn.hl7v2.conf.ProfileException;
/**
*
* This particular implementation of CodeStore retrieves valid codes and validates codeSystems using
* tables found in 'spec xml tables only' docs generated from the HL7 Messaging Workbench tool.
*
* Note: The codeSystem parameter value used in the following methods must be a concatenation of a
* coding authority and coding table number that is 4 digits long.
*
* Note: The current implementation only accepts a coding authority of HL7
*
* @author Neal Acharya
* @author Christian Ohr
*/
public class ProfileCodeStore extends AbstractCodeStore {
private Map<String, List<String>> codes = new HashMap<String, List<String>>();
/**
* Creates a ProfileCodeStore object that uses tables found in an 'spec xml tables only' xml doc
* specified by the input URI. The private field member tableDoc is created with content from
* the xml doc specified by the URI.
*
* @param uri the location of the specification XML file
*
* @throws ProfileException
* @throws IOException
*
*/
public ProfileCodeStore(String uri) throws ProfileException, IOException {
try {
if (uri == null) {
throw new ProfileException("The input url parameter cannot be null");
}
XMLReader reader = XMLReaderFactory.createXMLReader();
reader.setContentHandler(new ProfileCodeStoreHandler());
reader.parse(uri);
} catch (IOException e) {
throw e;
} catch (Exception e) {
throw new ProfileException(e.toString(), e);
}
}
/** As string constructor but accepts a URL object */
public ProfileCodeStore(URL url) throws ProfileException, IOException {
this(url.toExternalForm());
}
/**
* Retreives all codes for a given conformance profile and codeSystem. Note: The codeSystem
* parameter value must be a concatenation of a coding authority and coding table number that is
* 4 digits long.
*
* Note: The current implementation only accepts a coding authority of HL7
*
* @param codeSystem
* @return String[]
* @throws ProfileException
* @see ca.uhn.hl7v2.conf.store.CodeStore#getValidCodes(java.lang.String, java.lang.String)
*
*/
public String[] getValidCodes(String codeSystem) throws ProfileException {
List<String> result = getCodeTable(codeSystem);
if (result == null)
throw new ProfileException("Unknown code system: " + codeSystem);
return result.toArray(new String[result.size()]);
}
/**
* Validates the codeSytem against the input conformance profile. If valid then output is 'true'
* else 'false'. Note: The codeSystem parameter value must be a concatenation of a coding
* authority and coding table number that is 4 digits long.
*
* Note: The current implementation only accepts a coding authority of HL7
*
* @param codeSystem
*
* @return boolean
* @see ca.uhn.hl7v2.conf.store.CodeStore#knowsCodes(java.lang.String, java.lang.String)
*
*/
public boolean knowsCodes(String codeSystem) {
try {
return getCodeTable(codeSystem) != null;
} catch (ProfileException e) {
return false;
}
}
/**
* Retrieves the hl7Table Element from the tableDoc object defined by the table number in the
* input codeSystem.
*
* @param profileId
*
* @param codeSystem
* @return Element
* @throws ProfileException Element
*/
private List<String> getCodeTable(String codeSystem) throws ProfileException {
if (codeSystem == null) {
throw new ProfileException("The input codeSystem parameter cannot be null");
}
if (codeSystem.length() < 4) {
throw new ProfileException(
"The input codeSystem parameter cannot be less than 4 characters long");
}
// Extract the last 4 characters from the codeSystem param
String tableId = codeSystem.substring(codeSystem.length() - 4);
return codes.get(tableId);
}
private class ProfileCodeStoreHandler extends DefaultHandler {
private String currentTable;
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes)
throws SAXException {
if ("hl7table".equals(qName)) {
currentTable = attributes.getValue("id");
codes.put(currentTable, new ArrayList<String>());
}
if ("tableElement".equals(qName)) {
codes.get(currentTable).add(attributes.getValue("code"));
}
}
}
}