sascha@998: package de.intevation.flys.artifacts.datacage.templating;
sascha@998: 
sascha@998: import java.util.List;
sascha@998: import java.util.Collection;
sascha@998: import java.util.Map;
sascha@998: import java.util.ArrayList;
sascha@998: 
sascha@998: import javax.xml.xpath.XPathFunctionResolver;
sascha@998: import javax.xml.xpath.XPathFunction;
sascha@998: import javax.xml.xpath.XPathFunctionException;
sascha@998: 
sascha@998: import javax.xml.namespace.QName;
sascha@998: 
sascha@998: import org.apache.log4j.Logger;
sascha@998: 
felix@4594: 
felix@4594: /** Resolves functions (e.g. dc:contains) in Datacage/Meta-Data system. */
sascha@998: public class FunctionResolver
sascha@998: implements   XPathFunctionResolver
sascha@998: {
felix@4594:     /** Home logger. */
sascha@998:     private static Logger log = Logger.getLogger(FunctionResolver.class);
sascha@998: 
sascha@998:     public static final String FUNCTION_NAMESPACE_URI = "dc";
sascha@998: 
sascha@998:     public static final class Entry {
sascha@998: 
sascha@998:         String        name;
sascha@998:         XPathFunction function;
sascha@998:         int           arity;
sascha@998: 
sascha@998:         public Entry() {
sascha@998:         }
sascha@998: 
sascha@998:         public Entry(String name, XPathFunction function, int arity) {
sascha@998:             this.name     = name;
sascha@998:             this.function = function;
sascha@998:             this.arity    = arity;
sascha@998:         }
sascha@998:     } // class Entry
sascha@998: 
sascha@998:     public static final FunctionResolver FUNCTIONS = new FunctionResolver();
sascha@998: 
sascha@998:     static {
felix@1930:         /** Implementation of case-ignoring dc:contains. */
sascha@998:         FUNCTIONS.addFunction("contains", 2, new XPathFunction() {
sascha@998:             @Override
sascha@998:             public Object evaluate(List args) throws XPathFunctionException {
sascha@998:                 Object haystack = args.get(0);
sascha@998:                 Object needle   = args.get(1);
sascha@1716: 
sascha@1716:                 if (needle instanceof String) {
sascha@1716:                     needle = ((String)needle).toUpperCase();
sascha@1716:                 }
sascha@1716: 
sascha@998:                 try {
sascha@998:                     if (haystack instanceof Collection) {
sascha@998:                         return Boolean.valueOf(
sascha@998:                             ((Collection)haystack).contains(needle));
sascha@998:                     }
sascha@998: 
sascha@998:                     if (haystack instanceof Map) {
sascha@998:                         return Boolean.valueOf(
sascha@998:                             ((Map)haystack).containsKey(needle));
sascha@998:                     }
sascha@998: 
sascha@998:                     if (haystack instanceof Object []) {
sascha@998:                         for (Object straw: (Object [])haystack) {
sascha@998:                             if (straw.equals(needle)) {
sascha@998:                                 return Boolean.TRUE;
sascha@998:                             }
sascha@998:                         }
sascha@998:                     }
sascha@998: 
sascha@998:                     return Boolean.FALSE;
sascha@998:                 }
sascha@998:                 catch (Exception e) {
sascha@998:                     log.error(e);
sascha@998:                     throw new XPathFunctionException(e);
sascha@998:                 }
sascha@998:             }
sascha@998:         });
sascha@998:     }
sascha@998: 
felix@4594:     /** List of functions. */
sascha@998:     protected List<Entry> functions;
sascha@998: 
sascha@998:     public FunctionResolver() {
sascha@998:         functions = new ArrayList<Entry>();
sascha@998:     }
sascha@998: 
felix@4594:     /**
felix@4594:      * Create a new function.
felix@4594:      * @param name  Name of the function.
felix@4594:      * @param arity Number of arguments for function.
felix@4594:      * @param function the function itself.
felix@4594:      */
sascha@998:     public void addFunction(String name, int arity, XPathFunction function) {
sascha@998:         functions.add(new Entry(name, function, arity));
sascha@998:     }
sascha@998: 
sascha@998:     @Override
sascha@998:     public XPathFunction resolveFunction(QName functionName, int arity) {
sascha@998: 
sascha@998:         if (!functionName.getNamespaceURI().equals(FUNCTION_NAMESPACE_URI)) {
sascha@998:             return null;
sascha@998:         }
sascha@998: 
sascha@998:         String name = functionName.getLocalPart();
sascha@998:         for (Entry entry: functions) {
sascha@998:             if (entry.arity == arity && entry.name.equals(name)) {
sascha@998:                 return entry.function;
sascha@998:             }
sascha@998:         }
sascha@998: 
sascha@998:         return null;
sascha@998:     }
sascha@998: }
sascha@998: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :