org.argeo.api.acr/src/org/argeo/api/acr/NamespaceUtils.java

   1 package org.argeo.api.acr;
   2
   3 import java.util.Collections;
   4 import java.util.Comparator;
   5 import java.util.Iterator;
   6 import java.util.Objects;
   7 import java.util.Set;
   8 import java.util.function.Function;
   9
  10 import javax.xml.XMLConstants;
  11 import javax.xml.namespace.NamespaceContext;
  12 import javax.xml.namespace.QName;
  13
  14 public class NamespaceUtils {
  15
  16         public static ContentName parsePrefixedName(NamespaceContext nameSpaceContext, String nameWithPrefix) {
  17                 Objects.requireNonNull(nameWithPrefix, "Name cannot be null");
  18                 if (nameWithPrefix.charAt(0) == '{') {
  19                         return new ContentName(QName.valueOf(nameWithPrefix), nameSpaceContext);
  20                 }
  21                 int index = nameWithPrefix.indexOf(':');
  22                 if (index < 0) {
  23                         return new ContentName(nameWithPrefix);
  24                 }
  25                 String prefix = nameWithPrefix.substring(0, index);
  26                 // TODO deal with empty name?
  27                 String localName = nameWithPrefix.substring(index + 1);
  28                 String namespaceURI = nameSpaceContext.getNamespaceURI(prefix);
  29                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
  30                         throw new IllegalStateException("Prefix " + prefix + " is unbound.");
  31                 return new ContentName(namespaceURI, localName, prefix);
  32         }
  33
  34         public static String toPrefixedName(NamespaceContext nameSpaceContext, QName name) {
  35                 if (XMLConstants.NULL_NS_URI.equals(name.getNamespaceURI()))
  36                         return name.getLocalPart();
  37                 String prefix = nameSpaceContext.getPrefix(name.getNamespaceURI());
  38                 if (prefix == null)
  39                         throw new IllegalStateException("Namespace " + name.getNamespaceURI() + " is unbound.");
  40                 return prefix + ":" + name.getLocalPart();
  41         }
  42
  43         public final static Comparator<QName> QNAME_COMPARATOR = new Comparator<QName>() {
  44
  45                 @Override
  46                 public int compare(QName qn1, QName qn2) {
  47                         if (Objects.equals(qn1.getNamespaceURI(), qn2.getNamespaceURI())) {// same namespace
  48                                 return qn1.getLocalPart().compareTo(qn2.getLocalPart());
  49                         } else {
  50                                 return qn1.getNamespaceURI().compareTo(qn2.getNamespaceURI());
  51                         }
  52                 }
  53
  54         };
  55
  56         /** singleton */
  57         private NamespaceUtils() {
  58         }
  59
  60         /*
  61          * DEFAULT NAMESPACE CONTEXT OPERATIONS as specified in NamespaceContext
  62          */
  63         public static String getStandardPrefix(String namespaceURI) {
  64                 if (namespaceURI == null)
  65                         throw new IllegalArgumentException("Namespace URI cannot be null");
  66                 if (XMLConstants.XML_NS_URI.equals(namespaceURI))
  67                         return XMLConstants.XML_NS_PREFIX;
  68                 else if (XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(namespaceURI))
  69                         return XMLConstants.XMLNS_ATTRIBUTE;
  70                 return null;
  71         }
  72
  73         public static Iterator<String> getStandardPrefixes(String namespaceURI) {
  74                 String prefix = getStandardPrefix(namespaceURI);
  75                 if (prefix == null)
  76                         return null;
  77                 return Collections.singleton(prefix).iterator();
  78         }
  79
  80         public static String getStandardNamespaceURI(String prefix) {
  81                 if (prefix == null)
  82                         throw new IllegalArgumentException("Prefix cannot be null");
  83                 if (XMLConstants.XML_NS_PREFIX.equals(prefix))
  84                         return XMLConstants.XML_NS_URI;
  85                 else if (XMLConstants.XMLNS_ATTRIBUTE.equals(prefix))
  86                         return XMLConstants.XMLNS_ATTRIBUTE_NS_URI;
  87                 return null;
  88         }
  89
  90         public static String getNamespaceURI(Function<String, String> mapping, String prefix) {
  91                 String namespaceURI = NamespaceUtils.getStandardNamespaceURI(prefix);
  92                 if (namespaceURI != null)
  93                         return namespaceURI;
  94                 if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix))
  95                         return XMLConstants.NULL_NS_URI;
  96                 namespaceURI = mapping.apply(prefix);
  97                 if (namespaceURI != null)
  98                         return namespaceURI;
  99                 return XMLConstants.NULL_NS_URI;
 100         }
 101
 102         public static String getPrefix(Function<String, String> mapping, String namespaceURI) {
 103                 String prefix = NamespaceUtils.getStandardPrefix(namespaceURI);
 104                 if (prefix != null)
 105                         return prefix;
 106                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
 107                         return XMLConstants.DEFAULT_NS_PREFIX;
 108                 return mapping.apply(namespaceURI);
 109         }
 110
 111         public static Iterator<String> getPrefixes(Function<String, Set<String>> mapping, String namespaceURI) {
 112                 Iterator<String> standard = NamespaceUtils.getStandardPrefixes(namespaceURI);
 113                 if (standard != null)
 114                         return standard;
 115                 if (XMLConstants.NULL_NS_URI.equals(namespaceURI))
 116                         return Collections.singleton(XMLConstants.DEFAULT_NS_PREFIX).iterator();
 117                 Set<String> prefixes = mapping.apply(namespaceURI);
 118                 assert prefixes != null;
 119                 return prefixes.iterator();
 120         }
 121
 122 }