8236142: DocTrees should provide getCharacters(EntityTree)

Reviewed-by: prappo

Author: jonathan-gibbons

src/jdk.compiler/share/classes/com/sun/source/util/DocTrees.java

@@ -39,6 +39,8 @@
 
 import com.sun.source.doctree.DocCommentTree;
 import com.sun.source.doctree.DocTree;
+import com.sun.source.doctree.EntityTree;
+import com.sun.source.tree.CompilationUnitTree;
 
 /**
  * Provides access to syntax trees for doc comments.
@@ -202,19 +204,17 @@ public static DocTrees instance(ProcessingEnvironment env) {
      * @param root the compilation unit that contains tree
      */
     public abstract void printMessage(Diagnostic.Kind kind, CharSequence msg,
-            com.sun.source.doctree.DocTree t,
-            com.sun.source.doctree.DocCommentTree c,
-            com.sun.source.tree.CompilationUnitTree root);
+            DocTree t, DocCommentTree c, CompilationUnitTree root);
 
     /**
      * Sets the break iterator to compute the first sentence of
      * documentation comments.
-     * @param breakiterator a break iterator or {@code null} to specify the default
+     * @param breakIterator a break iterator or {@code null} to specify the default
      *                      sentence breaker
      *
      * @since 9
      */
-    public abstract void setBreakIterator(BreakIterator breakiterator);
+    public abstract void setBreakIterator(BreakIterator breakIterator);
 
     /**
      * Returns a utility object for creating {@code DocTree} objects.
@@ -223,4 +223,16 @@ public abstract void printMessage(Diagnostic.Kind kind, CharSequence msg,
      * @since 9
      */
     public abstract DocTreeFactory getDocTreeFactory();
+
+    /**
+     * Returns a string containing the characters for the entity in a given entity tree,
+     * or {@code null} if the tree does not represent a valid series of characters.
+     *
+     * <p>The interpretation of entities is based on section
+     * <a href="https://www.w3.org/TR/html52/syntax.html#character-references">8.1.4. Character references</a>
+     * in the HTML 5.2 specification.</p>
+     *
+     * @return a string containing the characters
+     */
+    public abstract String getCharacters(EntityTree tree);
 }

src/jdk.compiler/share/classes/com/sun/tools/doclint/Checker.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -295,18 +295,12 @@ public Void visitText(TextTree tree, Void ignore) {
     public Void visitEntity(EntityTree tree, Void ignore) {
         checkAllowsText(tree);
         markEnclosingTag(Flag.HAS_TEXT);
-        String name = tree.getName().toString();
-        if (name.startsWith("#")) {
-            int v = StringUtils.toLowerCase(name).startsWith("#x")
-                    ? Integer.parseInt(name.substring(2), 16)
-                    : Integer.parseInt(name.substring(1), 10);
-            if (!Entity.isValid(v)) {
-                env.messages.error(HTML, tree, "dc.entity.invalid", name);
-            }
-        } else if (!Entity.isValid(name)) {
-            env.messages.error(HTML, tree, "dc.entity.invalid", name);
+        String s = env.trees.getCharacters(tree);
+        if (s == null) {
+            env.messages.error(HTML, tree, "dc.entity.invalid", tree.getName());
         }
         return null;
+
     }
 
     void checkAllowsText(DocTree tree) {