From: markt <markt@13f79535-47bb-0310-9956-ffa450edef68>
Date: Tue, 6 Jul 2010 16:47:39 +0000 (+0000)
Subject: Improve fix for https://issues.apache.org/bugzilla/show_bug.cgi?id=49217
X-Git-Url: https://git.internetallee.de/?a=commitdiff_plain;h=a83072fbbbd494b734320aec23798e10daa59d51;p=tomcat7.0

Improve fix for https://issues.apache.org/bugzilla/show_bug.cgi?id=49217
Make sure identifiers meet the requirements of the JLS

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@960942 13f79535-47bb-0310-9956-ffa450edef68
---

diff --git a/java/org/apache/el/parser/AstDotSuffix.java b/java/org/apache/el/parser/AstDotSuffix.java
index d925c1159..5e964f1b6 100644
--- a/java/org/apache/el/parser/AstDotSuffix.java
+++ b/java/org/apache/el/parser/AstDotSuffix.java
@@ -41,7 +41,7 @@ public final class AstDotSuffix extends SimpleNode {
     
     @Override
     public void setImage(String image) {
-        if (Validation.isJavaKeyword(image)) {
+        if (!Validation.isIdentifier(image)) {
             throw new ELException("Can't use Java keyword as identifier");
         }
         this.image = image;
diff --git a/java/org/apache/el/parser/AstIdentifier.java b/java/org/apache/el/parser/AstIdentifier.java
index 2283a8db3..d4c477a98 100644
--- a/java/org/apache/el/parser/AstIdentifier.java
+++ b/java/org/apache/el/parser/AstIdentifier.java
@@ -128,7 +128,7 @@ public final class AstIdentifier extends SimpleNode {
 
     @Override
     public void setImage(String image) {
-        if (Validation.isJavaKeyword(image)) {
+        if (!Validation.isIdentifier(image)) {
             throw new ELException("Can't use Java keyword as identifier");
         }
         this.image = image;
diff --git a/java/org/apache/el/util/Validation.java b/java/org/apache/el/util/Validation.java
index df2eb5b49..b291fed11 100644
--- a/java/org/apache/el/util/Validation.java
+++ b/java/org/apache/el/util/Validation.java
@@ -19,15 +19,16 @@ package org.apache.el.util;
 
 public class Validation {
 
-    private static final String javaKeywords[] = { "abstract", "assert",
-        "boolean", "break", "byte", "case", "catch", "char", "class",
-        "const", "continue", "default", "do", "double", "else", "enum",
-        "extends", "final", "finally", "float", "for", "goto", "if",
-        "implements", "import", "instanceof", "int", "interface", "long",
-        "native", "new", "package", "private", "protected", "public",
-        "return", "short", "static", "strictfp", "super", "switch",
-        "synchronized", "this", "throw", "throws", "transient", "try",
-        "void", "volatile", "while" };
+    // Java keywords, boolean literals & the null literal in alphabetical order
+    private static final String invalidIdentifiers[] = { "abstract", "assert",
+        "boolean", "break", "byte", "case", "catch", "char", "class", "const",
+        "continue", "default", "do", "double", "else", "enum", "extends",
+        "false", "final", "finally", "float", "for", "goto", "if", "implements",
+        "import", "instanceof", "int", "interface", "long", "native", "new",
+        "null", "package", "private", "protected", "public", "return", "short",
+        "static", "strictfp", "super", "switch", "synchronized", "this",
+        "throw", "throws", "transient", "true", "try", "void", "volatile",
+        "while" };
     
     
     private Validation() {
@@ -35,16 +36,23 @@ public class Validation {
     }
     
     /**
-     * Test whether the argument is a Java keyword
+     * Test whether the argument is a Java identifier.
      */
-    public static boolean isJavaKeyword(String key) {
+    public static boolean isIdentifier(String key) {
+        
+        // Should not be the case but check to be sure
+        if (key == null || key.length() == 0) {
+            return false;
+        }
+        
+        // Check the list of known invalid values
         int i = 0;
-        int j = javaKeywords.length;
+        int j = invalidIdentifiers.length;
         while (i < j) {
             int k = (i + j) / 2;
-            int result = javaKeywords[k].compareTo(key);
+            int result = invalidIdentifiers[k].compareTo(key);
             if (result == 0) {
-                return true;
+                return false;
             }
             if (result < 0) {
                 i = k + 1;
@@ -52,6 +60,19 @@ public class Validation {
                 j = k;
             }
         }
-        return false;
+
+        // Check the start character that has more restrictions
+        if (!Character.isJavaIdentifierStart(key.charAt(0))) {
+            return false;
+        }
+
+        // Check each remaining character used is permitted
+        for (int idx = 1; idx < key.length(); idx++) {
+            if (!Character.isJavaIdentifierPart(key.charAt(idx))) {
+                return false;
+            }
+        }
+        
+        return true;
     }
 }
diff --git a/webapps/docs/changelog.xml b/webapps/docs/changelog.xml
index 819b7c839..9b30ea272 100644
--- a/webapps/docs/changelog.xml
+++ b/webapps/docs/changelog.xml
@@ -128,7 +128,8 @@
         MethodExpressions is used in EL. (markt)
       </fix>
       <fix>
-        <bug>49217</bug>: Prevent use of Java keywords in identifiers. (markt)
+        <bug>49217</bug>: Ensure that identifiers used in EL meet the
+        requirements of the Java Language Specification. (markt)
       </fix>
     </changelog>
   </subsection>