acr/NamespaceUtils.java

   1 package org.argeo.api.acr;
   2
   3 import java.util.Collections;
   4 import java.util.Iterator;
   5 import java.util.Objects;
   6 import java.util.Set;
   7 import java.util.function.Function;
   8
   9 import javax.xml.XMLConstants;
  10 import javax.xml.namespace.NamespaceContext;
  11 import javax.xml.namespace.QName;
  12
  13 public class NamespaceUtils {
  14
  15         public static ContentName parsePrefixedName(NamespaceContext nameSpaceContext, String nameWithPrefix) {
  16                 Objects.requireNonNull(nameWithPrefix, "Name cannot be null");
  17                 if (nameWithPrefix.charAt(0) == '{') {
  18                         return new ContentName(QName.valueOf(nameWithPrefix), nameSpaceContext);
  19                 }
  20                 int index = nameWithPrefix.indexOf(':');
  21                 if (index < 0) {
  22                         return new ContentName(nameWithPrefix);
  23                 }
  24                 String prefix = nameWithPrefix.substring(0, index);
  25                 // TODO deal with empty name?
  26                 String localName = nameWithPrefix.substring(index + 1);
  27                 String namespaceURI = nameSpaceContext.getNamespaceURI(prefix);
  28                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
  29                         throw new IllegalStateException("Prefix " + prefix + " is unbound.");
  30                 return new ContentName(namespaceURI, localName, prefix);
  31         }
  32
  33         public static String toPrefixedName(NamespaceContext nameSpaceContext, QName name) {
  34                 if (XMLConstants.NULL_NS_URI.equals(name.getNamespaceURI()))
  35                         return name.getLocalPart();
  36                 String prefix = nameSpaceContext.getPrefix(name.getNamespaceURI());
  37                 if (prefix == null)
  38                         throw new IllegalStateException("Namespace " + name.getNamespaceURI() + " is unbound.");
  39                 return prefix + ":" + name.getLocalPart();
  40         }
  41
  42         /** singleton */
  43         private NamespaceUtils() {
  44         }
  45
  46         /*
  47          * DEFAULT NAMESPACE CONTEXT OPERATIONS as specified in NamespaceContext
  48          */
  49         public static String getStandardPrefix(String namespaceURI) {
  50                 if (namespaceURI == null)
  51                         throw new IllegalArgumentException("Namespace URI cannot be null");
  52                 if (XMLConstants.XML_NS_URI.equals(namespaceURI))
  53                         return XMLConstants.XML_NS_PREFIX;
  54                 else if (XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(namespaceURI))
  55                         return XMLConstants.XMLNS_ATTRIBUTE;
  56                 return null;
  57         }
  58
  59         public static Iterator<String> getStandardPrefixes(String namespaceURI) {
  60                 String prefix = getStandardPrefix(namespaceURI);
  61                 if (prefix == null)
  62                         return null;
  63                 return Collections.singleton(prefix).iterator();
  64         }
  65
  66         public static String getStandardNamespaceURI(String prefix) {
  67                 if (prefix == null)
  68                         throw new IllegalArgumentException("Prefix cannot be null");
  69                 if (XMLConstants.XML_NS_PREFIX.equals(prefix))
  70                         return XMLConstants.XML_NS_URI;
  71                 else if (XMLConstants.XMLNS_ATTRIBUTE.equals(prefix))
  72                         return XMLConstants.XMLNS_ATTRIBUTE_NS_URI;
  73                 return null;
  74         }
  75
  76         public static String getNamespaceURI(Function<String, String> mapping, String prefix) {
  77                 String namespaceURI = NamespaceUtils.getStandardNamespaceURI(prefix);
  78                 if (namespaceURI != null)
  79                         return namespaceURI;
  80                 if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix))
  81                         return XMLConstants.NULL_NS_URI;
  82                 namespaceURI = mapping.apply(prefix);
  83                 if (namespaceURI != null)
  84                         return namespaceURI;
  85                 return XMLConstants.NULL_NS_URI;
  86         }
  87
  88         public static String getPrefix(Function<String, String> mapping, String namespaceURI) {
  89                 String prefix = NamespaceUtils.getStandardPrefix(namespaceURI);
  90                 if (prefix != null)
  91                         return prefix;
  92                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
  93                         return XMLConstants.DEFAULT_NS_PREFIX;
  94                 return mapping.apply(namespaceURI);
  95         }
  96
  97         public static Iterator<String> getPrefixes(Function<String, Set<String>> mapping, String namespaceURI) {
  98                 Iterator<String> standard = NamespaceUtils.getStandardPrefixes(namespaceURI);
  99                 if (standard != null)
 100                         return standard;
 101                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
 102                         return Collections.singleton(XMLConstants.DEFAULT_NS_PREFIX).iterator();
 103                 Set<String> prefixes = mapping.apply(namespaceURI);
 104                 assert prefixes != null;
 105                 return prefixes.iterator();
 106         }
 107
 108 }