### Eclipse Workspace Patch 1.0
#P groovy-core
Index: src/main/groovy/xml/MarkupBuilder.java
===================================================================
--- src/main/groovy/xml/MarkupBuilder.java	(revision 14844)
+++ src/main/groovy/xml/MarkupBuilder.java	(working copy)
@@ -306,7 +306,7 @@
      * @see #escapeXmlValue(String, boolean)
      */
     private String escapeAttributeValue(String value) {
-        return escapeXmlValue(value, true);
+        return escapeXmlValue(value, true, useDoubleQuotes);
     }
 
     /**
@@ -318,7 +318,7 @@
      * @see #escapeXmlValue(String, boolean)
      */
     private String escapeElementContent(String value) {
-        return escapeXmlValue(value, false);
+        return escapeXmlValue(value, false, useDoubleQuotes);
     }
 
     /**
@@ -337,57 +337,47 @@
      * </ul>
      * @param value The string to escape.
      * @param isAttrValue <code>true</code> if the string is to be used
-     * as an attribute value, otherwise <code>false</code>.
+     *   as an attribute value, otherwise <code>false</code>.
+     * @param useDoubleQuotes <code>true</code> if double quotes are used
+     *   as attribute delimiter, or <code>false</code> otherwise.
      * @return A new string in which all characters that require escaping
      * have been replaced with the corresponding XML entities.
      */
-    private String escapeXmlValue(String value, boolean isAttrValue) {
-        StringBuffer buffer = new StringBuffer(value);
-        for (int i = 0, n = buffer.length(); i < n; i++) {
-            switch (buffer.charAt(i)) {
+    private static String escapeXmlValue(String value,
+	                                 boolean isAttrValue,
+	                                 boolean useDoubleQuotes)
+    {
+        if (value == null)
+            throw new IllegalArgumentException();
+
+        StringBuffer buffer = null;
+
+        for (int i = 0, len = value.length(); i < len; i++) {
+            final char ch = value.charAt(i);
+            final String replacement;
+
+            switch (ch)
+            {
             case '&':
-                buffer.replace(i, i + 1, "&amp;");
-
-                // We're replacing a single character by a string of
-                // length 5, so we need to update the index variable
-                // and the total length.
-                i += 4;
-                n += 4;
+                replacement = "&amp;";
                 break;
 
             case '<':
-                buffer.replace(i, i + 1, "&lt;");
-
-                // We're replacing a single character by a string of
-                // length 4, so we need to update the index variable
-                // and the total length.
-                i += 3;
-                n += 3;
+                replacement = "&lt;";
                 break;
 
             case '>':
-                buffer.replace(i, i + 1, "&gt;");
-
-                // We're replacing a single character by a string of
-                // length 4, so we need to update the index variable
-                // and the total length.
-                i += 3;
-                n += 3;
+                replacement = "&gt;";
                 break;
 
             case '"':
                 // The double quote is only escaped if the value is for
                 // an attribute and the builder is configured to output
                 // attribute values inside double quotes.
-                if (isAttrValue && this.useDoubleQuotes) {
-                    buffer.replace(i, i + 1, "&quot;");
-
-                    // We're replacing a single character by a string of
-                    // length 6, so we need to update the index variable
-                    // and the total length.
-                    i += 5;
-                    n += 5;
-                }
+                if (isAttrValue && useDoubleQuotes)
+                    replacement = "&quot;";
+                else
+                    replacement = null;
                 break;
 
             case '\'':
@@ -395,23 +385,34 @@
                 // attribute, as opposed to element content, and if the
                 // builder is configured to surround attribute values with
                 // single quotes.
-                if (isAttrValue && !this.useDoubleQuotes){
-                    buffer.replace(i, i + 1, "&apos;");
-
-                    // We're replacing a single character by a string of
-                    // length 6, so we need to update the index variable
-                    // and the total length.
-                    i += 5;
-                    n += 5;
-                }
+                if (isAttrValue && !useDoubleQuotes)
+                    replacement = "&apos;";
+                else
+                    replacement = null;
                 break;
 
             default:
+                replacement = null;
                 break;
             }
+
+            if (replacement != null) {
+                // output differs from input; we write to our local buffer
+                if (buffer == null) {
+                    buffer = new StringBuffer((int)(1.1 * len));
+                    buffer.append(value.substring(0, i));
+                }
+
+                buffer.append(replacement);
+            } else if (buffer != null) {
+                // output differs from input; we write to our local buffer
+                buffer.append(ch);
+            } else {
+                // nothing to do
+            }
         }
 
-        return buffer.toString();
+        return buffer == null ? value : buffer.toString();
     }
 
     private void toState(int next, Object name) {