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1
17
18 package org.apache.jasper.compiler;
19
20 import java.util.*;
21 import java.io.*;
22 import javax.servlet.ServletContext  ;
23
24 import org.apache.jasper.JasperException;
25 import org.apache.jasper.xmlparser.ParserUtils;
26 import org.apache.jasper.xmlparser.TreeNode;
27 import org.apache.jasper.compiler.tagplugin.TagPlugin;
28 import org.apache.jasper.compiler.tagplugin.TagPluginContext;
29
30
34
35 public class TagPluginManager {
36
37 private static final String TAG_PLUGINS_XML = "/WEB-INF/tagPlugins.xml";
38 private static final String TAG_PLUGINS_ROOT_ELEM = "tag-plugins";
39
40 private boolean initialized = false;
41 private HashMap tagPlugins = null;
42 private ServletContext ctxt;
43 private PageInfo pageInfo;
44
45 public TagPluginManager(ServletContext ctxt) {
46 this.ctxt = ctxt;
47 }
48
49 public void apply(Node.Nodes page, ErrorDispatcher err, PageInfo pageInfo)
50 throws JasperException {
51
52 init(err);
53 if (tagPlugins == null || tagPlugins.size() == 0) {
54 return;
55 }
56
57 this.pageInfo = pageInfo;
58
59 page.visit(new Node.Visitor() {
60 public void visit(Node.CustomTag n)
61 throws JasperException {
62 invokePlugin(n);
63 visitBody(n);
64 }
65 });
66
67 }
68
69 private void init(ErrorDispatcher err) throws JasperException {
70 if (initialized)
71 return;
72
73 InputStream is = ctxt.getResourceAsStream(TAG_PLUGINS_XML);
74 if (is == null)
75 return;
76
77 TreeNode root = (new ParserUtils()).parseXMLDocument(TAG_PLUGINS_XML,
78 is);
79 if (root == null) {
80 return;
81 }
82
83 if (!TAG_PLUGINS_ROOT_ELEM.equals(root.getName())) {
84 err.jspError("jsp.error.plugin.wrongRootElement", TAG_PLUGINS_XML,
85 TAG_PLUGINS_ROOT_ELEM);
86 }
87
88 tagPlugins = new HashMap();
89 Iterator pluginList = root.findChildren("tag-plugin");
90 while (pluginList.hasNext()) {
91 TreeNode pluginNode = (TreeNode) pluginList.next();
92 TreeNode tagClassNode = pluginNode.findChild("tag-class");
93 if (tagClassNode == null) {
94 return;
96 }
97 String tagClass = tagClassNode.getBody().trim();
98 TreeNode pluginClassNode = pluginNode.findChild("plugin-class");
99 if (pluginClassNode == null) {
100 return;
102 }
103
104 String pluginClassStr = pluginClassNode.getBody();
105 TagPlugin tagPlugin = null;
106 try {
107 Class pluginClass = Class.forName(pluginClassStr);
108 tagPlugin = (TagPlugin) pluginClass.newInstance();
109 } catch (Exception e) {
110 throw new JasperException(e);
111 }
112 if (tagPlugin == null) {
113 return;
114 }
115 tagPlugins.put(tagClass, tagPlugin);
116 }
117 initialized = true;
118 }
119
120
126 private void invokePlugin(Node.CustomTag n) {
127 TagPlugin tagPlugin = (TagPlugin)
128 tagPlugins.get(n.getTagHandlerClass().getName());
129 if (tagPlugin == null) {
130 return;
131 }
132
133 TagPluginContext tagPluginContext = new TagPluginContextImpl(n, pageInfo);
134 n.setTagPluginContext(tagPluginContext);
135 tagPlugin.doTag(tagPluginContext);
136 }
137
138 static class TagPluginContextImpl implements TagPluginContext {
139 private Node.CustomTag node;
140 private Node.Nodes curNodes;
141 private PageInfo pageInfo;
142 private HashMap pluginAttributes;
143
144 TagPluginContextImpl(Node.CustomTag n, PageInfo pageInfo) {
145 this.node = n;
146 this.pageInfo = pageInfo;
147 curNodes = new Node.Nodes();
148 n.setAtETag(curNodes);
149 curNodes = new Node.Nodes();
150 n.setAtSTag(curNodes);
151 n.setUseTagPlugin(true);
152 pluginAttributes = new HashMap();
153 }
154
155 public TagPluginContext getParentContext() {
156 Node parent = node.getParent();
157 if (! (parent instanceof Node.CustomTag)) {
158 return null;
159 }
160 return ((Node.CustomTag) parent).getTagPluginContext();
161 }
162
163 public void setPluginAttribute(String key, Object value) {
164 pluginAttributes.put(key, value);
165 }
166
167 public Object getPluginAttribute(String key) {
168 return pluginAttributes.get(key);
169 }
170
171 public boolean isScriptless() {
172 return node.getChildInfo().isScriptless();
173 }
174
175 public boolean isConstantAttribute(String attribute) {
176 Node.JspAttribute attr = getNodeAttribute(attribute);
177 if (attr == null)
178 return false;
179 return attr.isLiteral();
180 }
181
182 public String getConstantAttribute(String attribute) {
183 Node.JspAttribute attr = getNodeAttribute(attribute);
184 if (attr == null)
185 return null;
186 return attr.getValue();
187 }
188
189 public boolean isAttributeSpecified(String attribute) {
190 return getNodeAttribute(attribute) != null;
191 }
192
193 public String getTemporaryVariableName() {
194 return JspUtil.nextTemporaryVariableName();
195 }
196
197 public void generateImport(String imp) {
198 pageInfo.addImport(imp);
199 }
200
201 public void generateDeclaration(String id, String text) {
202 if (pageInfo.isPluginDeclared(id)) {
203 return;
204 }
205 curNodes.add(new Node.Declaration(text, node.getStart(), null));
206 }
207
208 public void generateJavaSource(String sourceCode) {
209 curNodes.add(new Node.Scriptlet(sourceCode, node.getStart(),
210 null));
211 }
212
213 public void generateAttribute(String attributeName) {
214 curNodes.add(new Node.AttributeGenerator(node.getStart(),
215 attributeName,
216 node));
217 }
218
219 public void dontUseTagPlugin() {
220 node.setUseTagPlugin(false);
221 }
222
223 public void generateBody() {
224 curNodes = node.getAtETag();
228 }
229
230 private Node.JspAttribute getNodeAttribute(String attribute) {
231 Node.JspAttribute[] attrs = node.getJspAttributes();
232 for (int i=0; attrs != null && i < attrs.length; i++) {
233 if (attrs[i].getName().equals(attribute)) {
234 return attrs[i];
235 }
236 }
237 return null;
238 }
239 }
240 }
241 |
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