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1
52
53 package freemarker.ext.dom;
54
55 import freemarker.template.*;
56 import freemarker.core.Environment;
57 import org.w3c.dom.*;
58 import org.w3c.dom.traversal.NodeIterator;
59 import org.apache.xpath.*;
60 import org.apache.xpath.objects.*;
61 import org.apache.xml.utils.PrefixResolver;
62 import java.util.List  ;
63 import javax.xml.transform.TransformerException ;
64
65
71
72 class XalanXPathSupport implements XPathSupport {
73
74 private XPathContext xpathContext = new XPathContext();
75
76
81 private static final String ERRMSG_EMPTY_NODE_SET
82 = "Cannot perform an XPath query against an empty node set.";
83
84 synchronized public TemplateModel executeQuery(Object context, String xpathQuery) throws TemplateModelException {
85 if (!(context instanceof Node)) {
86 if (context != null) {
87 if (isNodeList(context)) {
88 int cnt = ((List ) context).size();
89 if (cnt != 0) {
90 throw new TemplateModelException(
91 "Cannot perform an XPath query against a node set of " + cnt
92 + " nodes. Expecting a single node.");
93 } else {
94 throw new TemplateModelException(ERRMSG_EMPTY_NODE_SET);
95 }
96 } else {
97 throw new TemplateModelException(
98 "Cannot perform an XPath query against a " + context.getClass().getName()
99 + ". Expecting a single org.w3c.dom.Node.");
100 }
101 } else {
102 throw new TemplateModelException(ERRMSG_EMPTY_NODE_SET);
103 }
104 }
105 Node node = (Node) context;
106 try {
107 XPath xpath = new XPath(xpathQuery, null, customPrefixResolver, XPath.SELECT, null);
108 int ctxtNode = xpathContext.getDTMHandleFromNode(node);
109 XObject xresult = xpath.execute(xpathContext, ctxtNode, customPrefixResolver);
110 if (xresult instanceof XNodeSet) {
111 NodeListModel result = new NodeListModel(node);
112 result.xpathSupport = this;
113 NodeIterator nodeIterator = xresult.nodeset();
114 Node n;
115 do {
116 n = nodeIterator.nextNode();
117 if (n != null) {
118 result.add(n);
119 }
120 } while (n != null);
121 return result.size() == 1 ? result.get(0) : result;
122 }
123 if (xresult instanceof XBoolean) {
124 return ((XBoolean) xresult).bool() ? TemplateBooleanModel.TRUE : TemplateBooleanModel.FALSE;
125 }
126 if (xresult instanceof XNull) {
127 return null;
128 }
129 if (xresult instanceof XString) {
130 return new SimpleScalar(xresult.toString());
131 }
132 if (xresult instanceof XNumber) {
133 return new SimpleNumber(new Double (((XNumber) xresult).num()));
134 }
135 throw new TemplateModelException("Cannot deal with type: " + xresult.getClass().getName());
136 } catch (TransformerException te) {
137 throw new TemplateModelException(te);
138 }
139 }
140
141 private static PrefixResolver customPrefixResolver = new PrefixResolver() {
142
143 public String getNamespaceForPrefix(String prefix, Node node) {
144 return getNamespaceForPrefix(prefix);
145 }
146
147 public String getNamespaceForPrefix(String prefix) {
148 if (prefix.equals(Template.DEFAULT_NAMESPACE_PREFIX)) {
149 return Environment.getCurrentEnvironment().getDefaultNS();
150 }
151 return Environment.getCurrentEnvironment().getNamespaceForPrefix(prefix);
152 }
153
154 public String getBaseIdentifier() {
155 return null;
156 }
157
158 public boolean handlesNullPrefixes() {
159 return false;
160 }
161 };
162
163
166 private static boolean isNodeList(Object context) {
167 if (context instanceof List ) {
168 List ls = (List ) context;
169 int ln = ls.size();
170 for (int i = 0; i < ln; i++) {
171 if (!(ls.get(i) instanceof Node)) {
172 return false;
173 }
174 }
175 return true;
176 } else {
177 return false;
178 }
179 }
180 } |
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