Hover for referenced entities

Fixes eclipse#663

Signed-off-by: azerr <[email protected]>

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/entities/EntitiesPlugin.java

@@ -14,8 +14,10 @@
 
 import org.eclipse.lemminx.extensions.entities.participants.EntitiesCompletionParticipant;
 import org.eclipse.lemminx.extensions.entities.participants.EntitiesDefinitionParticipant;
+import org.eclipse.lemminx.extensions.entities.participants.EntitiesHoverParticipant;
 import org.eclipse.lemminx.services.extensions.ICompletionParticipant;
 import org.eclipse.lemminx.services.extensions.IDefinitionParticipant;
+import org.eclipse.lemminx.services.extensions.IHoverParticipant;
 import org.eclipse.lemminx.services.extensions.IXMLExtension;
 import org.eclipse.lemminx.services.extensions.XMLExtensionsRegistry;
 import org.eclipse.lemminx.services.extensions.save.ISaveContext;
@@ -30,18 +32,23 @@ public class EntitiesPlugin implements IXMLExtension {
 
  private IDefinitionParticipant definitionParticipant;
 
+ private IHoverParticipant hoverParticipant;
+
  @Override
  public void start(InitializeParams params, XMLExtensionsRegistry registry) {
  completionParticipant = new EntitiesCompletionParticipant();
  registry.registerCompletionParticipant(completionParticipant);
  definitionParticipant = new EntitiesDefinitionParticipant();
  registry.registerDefinitionParticipant(definitionParticipant);
+ hoverParticipant = new EntitiesHoverParticipant();
+ registry.registerHoverParticipant(hoverParticipant);
  }
 
  @Override
  public void stop(XMLExtensionsRegistry registry) {
  registry.unregisterCompletionParticipant(completionParticipant);
  registry.unregisterDefinitionParticipant(definitionParticipant);
+ registry.unregisterHoverParticipant(hoverParticipant);
  }
 
  @Override

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/entities/participants/EntitiesHoverParticipant.java

@@ -0,0 +1,123 @@
+/**
+ * Copyright (c) 2020 Red Hat, Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v20.html
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ * Red Hat Inc. - initial API and implementation
+ */
+package org.eclipse.lemminx.extensions.entities.participants;
+
+import java.util.Collection;
+import java.util.List;
+
+import org.eclipse.lemminx.dom.DOMDocument;
+import org.eclipse.lemminx.dom.DOMDocumentType;
+import org.eclipse.lemminx.dom.DTDEntityDecl;
+import org.eclipse.lemminx.extensions.contentmodel.model.CMDocument;
+import org.eclipse.lemminx.extensions.contentmodel.model.ContentModelManager;
+import org.eclipse.lemminx.extensions.entities.EntitiesDocumentationUtils;
+import org.eclipse.lemminx.services.extensions.HoverParticipantAdapter;
+import org.eclipse.lemminx.services.extensions.IHoverRequest;
+import org.eclipse.lemminx.utils.XMLPositionUtility;
+import org.eclipse.lsp4j.MarkupContent;
+import org.eclipse.lsp4j.MarkupKind;
+import org.eclipse.lsp4j.Range;
+import org.w3c.dom.Entity;
+import org.w3c.dom.NamedNodeMap;
+
+/**
+ * Entities hover used in a text node (ex : &).
+ *
+ */
+public class EntitiesHoverParticipant extends HoverParticipantAdapter {
+
+ @Override
+ public String onText(IHoverRequest request) throws Exception {
+ DOMDocument document = request.getXMLDocument();
+ int offset = request.getOffset();
+ String text = document.getText();
+ int entityReferenceStart = XMLPositionUtility.getEntityReferenceStartOffset(text, offset);
+ if (entityReferenceStart == -1) {
+ return null;
+ }
+ // the start offset is the amp character, ignore it
+ entityReferenceStart++;
+ int entityReferenceEnd = XMLPositionUtility.getEntityReferenceEndOffset(text, offset);
+ // Find hover of the entity
+ // abcd &loc|al; --> in this case search local entity
+ if (text.charAt(entityReferenceEnd - 1) == ';') {
+ entityReferenceEnd--;
+ }
+ String entityName = text.substring(entityReferenceStart, entityReferenceEnd);
+ Range entityRange = XMLPositionUtility.createRange(entityReferenceStart, entityReferenceEnd, document);
+ MarkupContent entityContent = searchInInternalEntities(entityName, entityRange, document, request);
+ if (entityContent == null) {
+ entityContent = searchInExternalEntities(entityName, entityRange, document, request);
+ }
+ if (entityContent != null) {
+ return entityContent.getValue();
+ }
+ return null;
+ }
+
+ /**
+ * Search the given entity name in the internal entities.
+ * 
+ * @param document the DOM document.
+ * @param entityName the entity name.
+ * @param entityRange the entity range.
+ * @param locations the location links
+ */
+ private static MarkupContent searchInInternalEntities(String entityName, Range entityRange, DOMDocument document,
+ IHoverRequest request) {
+ DOMDocumentType docType = document.getDoctype();
+ if (docType == null) {
+ return null;
+ }
+ // Loop for entities declared in the DOCTYPE of the document
+ NamedNodeMap entities = docType.getEntities();
+ for (int i = 0; i < entities.getLength(); i++) {
+ DTDEntityDecl entity = (DTDEntityDecl) entities.item(i);
+ if (entityName.equals(entityName)) {
+ boolean markdown = request.canSupportMarkupKind(MarkupKind.MARKDOWN);
+ return EntitiesDocumentationUtils.getDocumentation(entity.getName(), entity.getNotationName(), true,
+ false, markdown);
+ }
+ }
+ return null;
+ }
+
+ /**
+ * Search the given entity name in the external entities.
+ * 
+ * @param document the DOM document.
+ * @param entityName the entity name.
+ * @param entityRange the entity range.
+ * @param locations the location links
+ * @param request the definition request.
+ * @return
+ */
+ private static MarkupContent searchInExternalEntities(String entityName, Range entityRange, DOMDocument document,
+ IHoverRequest request) {
+ ContentModelManager contentModelManager = request.getComponent(ContentModelManager.class);
+ Collection<CMDocument> cmDocuments = contentModelManager.findCMDocument(document, null, false);
+ for (CMDocument cmDocument : cmDocuments) {
+ List<Entity> entities = cmDocument.getEntities();
+ for (Entity ent : entities) {
+ DTDEntityDecl entity = (DTDEntityDecl) ent;
+ if (entityName.equals(entityName)) {
+ boolean markdown = request.canSupportMarkupKind(MarkupKind.MARKDOWN);
+ return EntitiesDocumentationUtils.getDocumentation(entity.getName(), entity.getNotationName(), true,
+ false, markdown);
+ }
+ }
+ }
+ return null;
+ }
+
+}