MIME4J-304 DecoderUtil::decodeEncodedWords without REGEXP (#50)
diff --git a/core/src/main/java/org/apache/james/mime4j/codec/DecoderUtil.java b/core/src/main/java/org/apache/james/mime4j/codec/DecoderUtil.java
index 60aa31d..8d37f8b 100644
--- a/core/src/main/java/org/apache/james/mime4j/codec/DecoderUtil.java
+++ b/core/src/main/java/org/apache/james/mime4j/codec/DecoderUtil.java
@@ -24,8 +24,6 @@
import java.nio.charset.Charset;
import java.util.Collections;
import java.util.Map;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
import org.apache.james.mime4j.io.InputStreams;
import org.apache.james.mime4j.util.ByteArrayBuffer;
@@ -36,9 +34,6 @@
*/
public class DecoderUtil {
- private static final Pattern PATTERN_ENCODED_WORD = Pattern.compile(
- "=\\?(.+?)\\?(\\w)\\?(.*?)\\?=", Pattern.DOTALL);
-
/**
* Decodes a string containing quoted-printable encoded data.
*
@@ -194,42 +189,57 @@
public static String decodeEncodedWords(String body, DecodeMonitor monitor, Charset fallback,
Map<Charset, Charset> charsetOverrides)
throws IllegalArgumentException {
- int tailIndex = 0;
- boolean lastMatchValid = false;
StringBuilder sb = new StringBuilder();
+ int position = 0;
- for (Matcher matcher = PATTERN_ENCODED_WORD.matcher(body); matcher.find();) {
- String separator = body.substring(tailIndex, matcher.start());
- String mimeCharset = matcher.group(1);
- String encoding = matcher.group(2);
- String encodedText = matcher.group(3);
-
- if (encodedText.isEmpty())
- return "";
-
- String decoded;
- decoded = tryDecodeEncodedWord(mimeCharset, encoding, encodedText, monitor, fallback, charsetOverrides);
- if (decoded == null) {
- sb.append(separator);
- sb.append(matcher.group(0));
- } else {
- if (!lastMatchValid || !CharsetUtil.isWhitespace(separator)) {
- sb.append(separator);
+ while (position < body.length()) {
+ int startPattern = body.indexOf("=?", position);
+ if (startPattern < 0) {
+ if (position == 0) {
+ return body;
}
- sb.append(decoded);
+ sb.append(body, position, body.length());
+ break;
}
- tailIndex = matcher.end();
- lastMatchValid = decoded != null;
- }
+ int charsetEnd = body.indexOf('?', startPattern + 2);
+ int encodingEnd = body.indexOf('?', charsetEnd + 1);
+ int encodedTextEnd = body.indexOf("?=", encodingEnd + 1);
- if (tailIndex == 0) {
- return body;
- } else {
- sb.append(body.substring(tailIndex));
- return sb.toString();
+ if (charsetEnd < 0 || encodingEnd < 0 || encodedTextEnd < 0) {
+ // Invalid pattern
+ sb.append(body, position, startPattern + 2);
+ position = startPattern + 2;
+ } else if (encodingEnd == encodedTextEnd) {
+ sb.append(body, position, Math.min(encodedTextEnd + 2, body.length()));
+ position = encodedTextEnd +2;
+ } else {
+ String separator = body.substring(position, startPattern);
+ if ((!CharsetUtil.isWhitespace(separator) || position == 0) && !separator.isEmpty()) {
+ sb.append(separator);
+ }
+ String mimeCharset = body.substring(startPattern + 2, charsetEnd);
+ String encoding = body.substring(charsetEnd + 1, encodingEnd);
+ String encodedText = body.substring(encodingEnd + 1, encodedTextEnd);
+
+ if (encodedText.isEmpty()) {
+ position = encodedTextEnd + 2;
+ continue;
+ }
+ String decoded;
+ decoded = tryDecodeEncodedWord(mimeCharset, encoding, encodedText, monitor, fallback, charsetOverrides);
+ if (decoded != null) {
+ if (!CharsetUtil.isWhitespace(decoded) && !decoded.isEmpty()) {
+ sb.append(decoded);
+ }
+ } else {
+ sb.append(body, startPattern, encodedTextEnd + 2);
+ }
+ position = encodedTextEnd + 2;
+ }
}
+ return sb.toString();
}
// return null on error
