This is an automated email from the ASF dual-hosted git repository.

btellier pushed a commit to branch 3.9.x
in repository https://gitbox.apache.org/repos/asf/james-project.git

commit 5ed5a146d40f6f38f0f0b3c3dd72368901bad416
Author: Benoit TELLIER <[email protected]>
AuthorDate: Wed Nov 12 17:48:15 2025 +0100

    JAMES-4086 FoldLongLines: folded content exceeding line length (#2851)
---
 .../james/transport/mailets/FoldLongLines.java     |  6 +-
 .../apache/james/transport/mailets/MimeUtil.java   | 80 ----------------------
 .../james/transport/mailets/FoldLongLinesTest.java | 44 +++++++++++-
 3 files changed, 46 insertions(+), 84 deletions(-)

diff --git 
a/mailet/standard/src/main/java/org/apache/james/transport/mailets/FoldLongLines.java
 
b/mailet/standard/src/main/java/org/apache/james/transport/mailets/FoldLongLines.java
index 01608c9454..3ebf19979e 100644
--- 
a/mailet/standard/src/main/java/org/apache/james/transport/mailets/FoldLongLines.java
+++ 
b/mailet/standard/src/main/java/org/apache/james/transport/mailets/FoldLongLines.java
@@ -26,6 +26,7 @@ import jakarta.mail.Header;
 import jakarta.mail.MessagingException;
 
 import org.apache.commons.lang3.stream.Streams;
+import org.apache.james.mime4j.util.MimeUtil;
 import org.apache.mailet.Mail;
 import org.apache.mailet.base.GenericMailet;
 
@@ -94,8 +95,9 @@ public class FoldLongLines extends GenericMailet {
 
     private String fold(Header header) {
         int headerNameLength = header.getName().length() + 
HEADER_SEPARATOR.length();
-        // TODO After new release of mime4j with commit 
https://github.com/apache/james-mime4j/commit/66a09219457854c7a26e5b7c0e4c9dd59b4b0c32,
 update to use MimeUtil of mime4j and remove MimeUtil class file
-        return MimeUtil.fold(header.getValue(), headerNameLength, 
maxCharacters);
+        String unfold = MimeUtil.unfold(header.getValue());
+        String res = MimeUtil.fold(unfold, headerNameLength, maxCharacters);
+        return res;
     }
 
     private boolean exceedLineLimit(Header header) {
diff --git 
a/mailet/standard/src/main/java/org/apache/james/transport/mailets/MimeUtil.java
 
b/mailet/standard/src/main/java/org/apache/james/transport/mailets/MimeUtil.java
deleted file mode 100644
index ef6213a57d..0000000000
--- 
a/mailet/standard/src/main/java/org/apache/james/transport/mailets/MimeUtil.java
+++ /dev/null
@@ -1,80 +0,0 @@
-/****************************************************************
- * Licensed to the Apache Software Foundation (ASF) under one   *
- * or more contributor license agreements.  See the NOTICE file *
- * distributed with this work for additional information        *
- * regarding copyright ownership.  The ASF licenses this file   *
- * to you under the Apache License, Version 2.0 (the            *
- * "License"); you may not use this file except in compliance   *
- * with the License.  You may obtain a copy of the License at   *
- *                                                              *
- *   http://www.apache.org/licenses/LICENSE-2.0                 *
- *                                                              *
- * Unless required by applicable law or agreed to in writing,   *
- * software distributed under the License is distributed on an  *
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
- * KIND, either express or implied.  See the License for the    *
- * specific language governing permissions and limitations      *
- * under the License.                                           *
- ****************************************************************/
-
-package org.apache.james.transport.mailets;
-
-// TODO After new release of mime4j with commit 
https://github.com/apache/james-mime4j/commit/66a09219457854c7a26e5b7c0e4c9dd59b4b0c32,
 remove this class
-public class MimeUtil {
-    /**
-     * Splits the specified string into a multiple-line representation with
-     * lines no longer than the maximum number of characters (because the line 
might contain
-     * encoded words; see <a href='http://www.faqs.org/rfcs/rfc2047.html'>RFC
-     * 2047</a> section 2). If the string contains non-whitespace sequences
-     * longer than the maximum number of characters a line break is inserted 
at the whitespace
-     * character following the sequence resulting in a line longer than the 
maximum number of
-     * characters.
-     *
-     * @param s
-     *            string to split.
-     * @param usedCharacters
-     *            number of characters already used up. Usually the number of
-     *            characters for header field name plus colon and one space.
-     * @param maxCharacters
-     *            maximum number of characters
-     * @return a multiple-line representation of the given string.
-     */
-    public static String fold(String s, int usedCharacters, int maxCharacters) 
{
-        final int length = s.length();
-        if (usedCharacters + length <= maxCharacters) {
-            return s;
-        }
-
-        StringBuilder sb = new StringBuilder();
-
-        int lastLineBreak = -usedCharacters;
-        int wspIdx = indexOfWsp(s, 0);
-        while (true) {
-            if (wspIdx == length) {
-                sb.append(s.substring(Math.max(0, lastLineBreak)));
-                return sb.toString();
-            }
-
-            int nextWspIdx = indexOfWsp(s, wspIdx + 1);
-
-            if (nextWspIdx - lastLineBreak > maxCharacters) {
-                sb.append(s, Math.max(0, lastLineBreak), wspIdx);
-                sb.append("\r\n");
-                lastLineBreak = wspIdx;
-            }
-
-            wspIdx = nextWspIdx;
-        }
-    }
-
-    private static int indexOfWsp(String s, int fromIndex) {
-        final int len = s.length();
-        for (int index = fromIndex; index < len; index++) {
-            char c = s.charAt(index);
-            if (c == ' ' || c == '\t') {
-                return index;
-            }
-        }
-        return len;
-    }
-}
diff --git 
a/mailet/standard/src/test/java/org/apache/james/transport/mailets/FoldLongLinesTest.java
 
b/mailet/standard/src/test/java/org/apache/james/transport/mailets/FoldLongLinesTest.java
index 37a15f59b6..77be5ccced 100644
--- 
a/mailet/standard/src/test/java/org/apache/james/transport/mailets/FoldLongLinesTest.java
+++ 
b/mailet/standard/src/test/java/org/apache/james/transport/mailets/FoldLongLinesTest.java
@@ -90,8 +90,7 @@ public class FoldLongLinesTest {
 
         List<Header> headers = 
Streams.of(mail.getMessage().getAllHeaders()).filter(header -> 
header.getName().equals(HEADER_NAME)).toList();
         assertThat(headers).hasSize(1);
-        assertThat(headers.getFirst().getValue()).isEqualTo("<a1@gmailcom>\n" +
-            "<a2@gmailcom>\r\n" +
+        
assertThat(headers.getFirst().getValue()).isEqualTo("<a1@gmailcom><a2@gmailcom>\r\n"
 +
             " <a3@gmailcom> <a4@gmailcom>");
     }
 
@@ -159,6 +158,47 @@ public class FoldLongLinesTest {
         });
     }
 
+    @Test
+    void shouldBeIdempotent() throws Exception {
+        FakeMailetConfig mailetConfig = FakeMailetConfig.builder()
+            .mailetName("Test")
+            .mailetContext(mailetContext)
+            .setProperty(MAX_CHARACTERS_PARAMETER_NAME, "40")
+            .build();
+        foldMailet.init(mailetConfig);
+
+        Mail mail = FakeMail.builder()
+            .name("mail").mimeMessage(MimeMessageBuilder.mimeMessageBuilder()
+                .addHeader(HEADER_NAME, "a".repeat(40) + "\r\n a")
+                .build())
+            .build();
+        foldMailet.service(mail);
+
+        assertThat(mail.getMessage().getHeader(HEADER_NAME)[0])
+            .isEqualTo("a".repeat(40) + "\r\n a");
+    }
+
+    @Test
+    void shouldTolerateLongerFoldedLines() throws Exception {
+        FakeMailetConfig mailetConfig = FakeMailetConfig.builder()
+            .mailetName("Test")
+            .mailetContext(mailetContext)
+            .setProperty(MAX_CHARACTERS_PARAMETER_NAME, "40")
+            .build();
+        foldMailet.init(mailetConfig);
+
+        Mail mail = FakeMail.builder()
+            .name("mail").mimeMessage(MimeMessageBuilder.mimeMessageBuilder()
+                .addHeader(HEADER_NAME, "a a".repeat(20) + "\r\n a")
+                .build())
+            .build();
+        foldMailet.service(mail);
+
+        assertThat(mail.getMessage().getHeader(HEADER_NAME)[0])
+            .isEqualTo("a aa aa aa aa aa aa aa aa aa\r\n" +
+                " aa aa aa aa aa aa aa aa aa aa a a");
+    }
+
     @Test
     void 
serviceShouldNotChangeTheRelativePositionOfTheHeaderThatHasTheSameNameAsHeadersWithLongLine()
 throws Exception {
         FakeMailetConfig mailetConfig = FakeMailetConfig.builder()


---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to