src/share/classes/java/util/regex/Matcher.java

*** 686,696 ****
       *
       * </ol>
       *
       * <p> The replacement string may contain references to subsequences
       * captured during the previous match: Each occurrence of
!      * <tt>$</tt>&lt;<i>name</i>&gt; or <tt>$</tt><i>g</i>
       * will be replaced by the result of evaluating the corresponding
       * {@link #group(String) group(name)} or {@link #group(int) group(g)</tt>}
       * respectively. For  <tt>$</tt><i>g</i><tt></tt>,
       * the first number after the <tt>$</tt> is always treated as part of
       * the group reference. Subsequent numbers are incorporated into g if
--- 686,696 ----
       *
       * </ol>
       *
       * <p> The replacement string may contain references to subsequences
       * captured during the previous match: Each occurrence of
!      * <tt>${</tt><i>name</i><tt>}</tt> or <tt>$</tt><i>g</i>
       * will be replaced by the result of evaluating the corresponding
       * {@link #group(String) group(name)} or {@link #group(int) group(g)</tt>}
       * respectively. For  <tt>$</tt><i>g</i><tt></tt>,
       * the first number after the <tt>$</tt> is always treated as part of
       * the group reference. Subsequent numbers are incorporated into g if
*** 768,778 ****
                  // this "$" is the last character in replacement
                  // string in current implementation, a IAE might be
                  // more appropriate.
                  nextChar = replacement.charAt(cursor);
                  int refNum = -1;
!                 if (nextChar == '<') {
                      cursor++;
                      StringBuilder gsb = new StringBuilder();
                      while (cursor < replacement.length()) {
                          nextChar = replacement.charAt(cursor);
                          if (ASCII.isLower(nextChar) ||
--- 768,778 ----
                  // this "$" is the last character in replacement
                  // string in current implementation, a IAE might be
                  // more appropriate.
                  nextChar = replacement.charAt(cursor);
                  int refNum = -1;
!                 if (nextChar == '{') {
                      cursor++;
                      StringBuilder gsb = new StringBuilder();
                      while (cursor < replacement.length()) {
                          nextChar = replacement.charAt(cursor);
                          if (ASCII.isLower(nextChar) ||
*** 785,801 ****
                          }
                      }
                      if (gsb.length() == 0)
                          throw new IllegalArgumentException(
                              "named capturing group has 0 length name");
!                     if (nextChar != '>')
                          throw new IllegalArgumentException(
!                             "named capturing group is missing trailing '>'");
                      String gname = gsb.toString();
                      if (!parentPattern.namedGroups().containsKey(gname))
                          throw new IllegalArgumentException(
!                             "No group with name <" + gname + ">");
                      refNum = parentPattern.namedGroups().get(gname);
                      cursor++;
                  } else {
                      // The first number is always a group
                      refNum = (int)nextChar - '0';
--- 785,805 ----
                          }
                      }
                      if (gsb.length() == 0)
                          throw new IllegalArgumentException(
                              "named capturing group has 0 length name");
!                     if (nextChar != '}')
                          throw new IllegalArgumentException(
!                             "named capturing group is missing trailing '}'");
                      String gname = gsb.toString();
+                     if (ASCII.isDigit(gname.charAt(0)))
+                         throw new IllegalArgumentException(
+                             "capturing group name {" + gname +
+                             "} starts with digit character");
                      if (!parentPattern.namedGroups().containsKey(gname))
                          throw new IllegalArgumentException(
!                             "No group with name {" + gname + "}");
                      refNum = parentPattern.namedGroups().get(gname);
                      cursor++;
                  } else {
                      // The first number is always a group
                      refNum = (int)nextChar - '0';