From a30445c2a40ebc0e449c7b7605fdc202c48e00d8 Mon Sep 17 00:00:00 2001
From: Vlad Dumitrescu <vladdu55@gmail.com>
Date: Thu, 20 Oct 2011 14:29:59 +0200
Subject: [PATCH 1/2] workaround for Java bug
 http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6242664

Java 1.5 has a bug where detecting codepoint offsets in strings that are
created by String.substring() gives wrong results. The new implementation
uses a different method, avoinding the issue.

The following code will crash without the fix:
        final String s = "abcdefg";
        final String ss = s.substring(3, 6);
        final int[] cps = OtpErlangString.stringToCodePoints(ss);
---
 .../ericsson/otp/erlang/OtpErlangString.java    | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpErlangString.java b/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpErlangString.java
index 23734bf83bc3..2d3a5a5d1c44 100644
--- a/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpErlangString.java
+++ b/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpErlangString.java
@@ -154,13 +154,16 @@ protected int doHashCode() {
      *         Unicode code points
      */
 
-    public static int[] stringToCodePoints(final String s) {
-	final int m = s.codePointCount(0, s.length());
-	final int [] codePoints = new int[m];
-	for (int i = 0, j = 0;  j < m;  i = s.offsetByCodePoints(i, 1), j++) {
-	    codePoints[j] = s.codePointAt(i);
-	}
-	return codePoints;
+   public static int[] stringToCodePoints(final String s) {
+        final int m = s.codePointCount(0, s.length());
+        final int[] codePoints = new int[m];
+        int j = 0;
+        for (int offset = 0; offset < s.length();) {
+            final int codepoint = s.codePointAt(offset);
+            codePoints[j++] = codepoint;
+            offset += Character.charCount(codepoint);
+        }
+        return codePoints;
     }
 
     /**

From e01d6f39b940d917ae445d8428b154de87888000 Mon Sep 17 00:00:00 2001
From: Vlad Dumitrescu <vladdu55@gmail.com>
Date: Sun, 13 Nov 2011 14:58:06 +0100
Subject: [PATCH 2/2] add test for Java string bug

---
 lib/jinterface/test/nc_SUITE.erl                   | 7 +++++--
 lib/jinterface/test/nc_SUITE_data/echo_server.java | 6 ++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/jinterface/test/nc_SUITE.erl b/lib/jinterface/test/nc_SUITE.erl
index da54f5bf51b0..9c88400c2a87 100644
--- a/lib/jinterface/test/nc_SUITE.erl
+++ b/lib/jinterface/test/nc_SUITE.erl
@@ -296,7 +296,8 @@ lists_roundtrip_2(Config) when is_list(Config) ->
 	  {[z,23|24],tail3},
 	  {[z|25],tail3},
 	  {"abc123",sub3atom},
-	  {"abc",sub3atom}
+	  {"abc",sub3atom},
+	  {"abcdefg",codepointBug}
 	 ],
     Trans =
 	fun ([_|T], tail) ->
@@ -308,7 +309,9 @@ lists_roundtrip_2(Config) when is_list(Config) ->
 	    (L, tail3) when is_list(L) ->
 		null;
 	    ([_,_,_|L], sub3atom) ->
-		list_to_atom(L)
+		list_to_atom(L);
+	    (L, codepointBug) ->
+		L
 	end,
     OutTrans =
 	fun ({L,Twist}) ->
diff --git a/lib/jinterface/test/nc_SUITE_data/echo_server.java b/lib/jinterface/test/nc_SUITE_data/echo_server.java
index 0550e4beb1aa..5ecb5b72a72f 100644
--- a/lib/jinterface/test/nc_SUITE_data/echo_server.java
+++ b/lib/jinterface/test/nc_SUITE_data/echo_server.java
@@ -202,6 +202,12 @@ private static OtpErlangObject twist(final OtpErlangObject i,
 		final OtpErlangAtom o = new OtpErlangAtom(s.stringValue()
 			.substring(3));
 		return o;
+	    } else if (atomValue.equals("codepointBug")
+		    && i instanceof OtpErlangString) {
+		final OtpErlangString s = (OtpErlangString) i;
+		final String ss = s.stringValue().substring(3, 6);
+		final int[] cps = OtpErlangString.stringToCodePoints(ss);
+		return s;
 	    } else if (atomValue.equals("utf8")) {
 		if (i instanceof OtpErlangString) {
 		    final OtpErlangString s = (OtpErlangString) i;