Nice manifest writer

aQute.libg/src/aQute/lib/manifest/ManifestUtil.java

@@ -4,16 +4,23 @@
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Comparator;
+import java.util.HashSet;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Objects;
+import java.util.Set;
 import java.util.jar.Attributes;
 import java.util.jar.Attributes.Name;
 import java.util.jar.Manifest;
 import java.util.stream.Stream;
 
+import org.osgi.framework.Constants;
+
 /**
  * Unfortunately we have to write our own manifest :-( because of a stupid bug
  * in the manifest code. It tries to handle UTF-8 but the way it does it it
@@ -40,14 +47,41 @@ public final class ManifestUtil {
 	private static final byte[]				EOL				= new byte[] {
 		'\r', '\n'
 	};
+	private static final byte[]				EOL_INDENT		= new byte[] {
+		'\r', '\n', ' '
+	};
 	private static final byte[]				SEPARATOR		= new byte[] {
 		':', ' '
 	};
 	private static final int				MAX_LENGTH		= 72 - EOL.length;
 
+	@SuppressWarnings("deprecation")
+	private static final Set<String> NICE_HEADERS = new HashSet<>(
+        Arrays.asList(
+                Constants.IMPORT_PACKAGE,
+                Constants.DYNAMICIMPORT_PACKAGE,
+                Constants.IMPORT_SERVICE,
+                Constants.REQUIRE_CAPABILITY,
+                Constants.EXPORT_PACKAGE,
+                Constants.EXPORT_SERVICE,
+                Constants.PROVIDE_CAPABILITY,
+                Constants.REQUIRE_BUNDLE,
+			Constants.BUNDLE_CLASSPATH, "Private-Package"
+        )
+);
+
 	private ManifestUtil() {}
 
+	/**
+	 * Writes out the manifest, nicely formatted. Use
+	 * {@link #write(Manifest, OutputStream, boolean)} to control 'nice'
+	 * formatting.
+	 */
 	public static void write(Manifest manifest, OutputStream out) throws IOException {
+		write(manifest, out, true);
+	}
+
+	public static void write(Manifest manifest, OutputStream out, boolean nice) throws IOException {
 		Attributes mainAttributes = manifest.getMainAttributes();
 		Stream<Entry<Name, String>> sortedAttributes = sortedAttributes(mainAttributes);
 
@@ -58,12 +92,12 @@ public static void write(Manifest manifest, OutputStream out) throws IOException
 			versionValue = mainAttributes.getValue(versionName);
 		}
 		if (versionValue != null) {
-			writeEntry(out, versionName, versionValue);
+			writeEntry(out, versionName, versionValue, nice);
 			Name filterName = versionName;
 			// Name.equals is case-insensitive
 			sortedAttributes = sortedAttributes.filter(e -> !Objects.equals(e.getKey(), filterName));
 		}
-		writeAttributes(out, sortedAttributes);
+		writeAttributes(out, sortedAttributes, nice);
 		out.write(EOL);
 
 		for (Iterator<Entry<String, Attributes>> iterator = manifest.getEntries()
@@ -72,8 +106,8 @@ public static void write(Manifest manifest, OutputStream out) throws IOException
 			.sorted(Entry.comparingByKey())
 			.iterator(); iterator.hasNext();) {
 			Entry<String, Attributes> entry = iterator.next();
-			writeEntry(out, NAME, entry.getKey());
-			writeAttributes(out, sortedAttributes(entry.getValue()));
+			writeEntry(out, NAME, entry.getKey(), nice);
+			writeAttributes(out, sortedAttributes(entry.getValue()), nice);
 			out.write(EOL);
 		}
 
@@ -83,11 +117,42 @@ public static void write(Manifest manifest, OutputStream out) throws IOException
 	/**
 	 * Write out an entry, handling proper unicode and line length constraints
 	 */
-	private static void writeEntry(OutputStream out, Name name, String value) throws IOException {
-		int width = write(out, 0, name.toString());
-		width = write(out, width, SEPARATOR);
-		write(out, width, value);
-		out.write(EOL);
+	private static void writeEntry(OutputStream out, Name name, String value, boolean nice) throws IOException {
+
+		if (nice && NICE_HEADERS.contains(name.toString())) {
+			int width = write(out, 0, name.toString());
+			width = write(out, width, SEPARATOR);
+
+			if (value == null || value.isEmpty()) {
+				// could be a Multi-Release Jar
+				write(out, 0, EOL);
+				return;
+			}
+
+			String[] parts = parseDelimitedString(value, ",");
+			if (parts.length > 1) {
+				write(out, 0, EOL_INDENT);
+				width = 1;
+			}
+
+			for (int i = 0; i < parts.length; i++) {
+				if (i < parts.length - 1) {
+					width = write(out, width, parts[i] + ",");
+					write(out, 0, EOL_INDENT);
+				} else {
+					width = write(out, width, parts[i]);
+					write(out, 0, EOL);
+				}
+				width = 1;
+			}
+		}
+		else {
+			int width = write(out, 0, name.toString());
+			width = write(out, width, SEPARATOR);
+            write(out, width, value);
+            write(out, 0, EOL);
+		}
+
 	}
 
 	/**
@@ -119,8 +184,7 @@ private static int write(OutputStream out, int width, String s) throws IOExcepti
 	private static int write(OutputStream out, int width, byte[] bytes) throws IOException {
 		for (int position = 0, limit = bytes.length, remaining; (remaining = limit - position) > 0;) {
 			if (width >= MAX_LENGTH) {
-				out.write(EOL);
-				out.write(' ');
+				out.write(EOL_INDENT);
 				width = 1;
 			}
 			int count = Math.min(MAX_LENGTH - width, remaining);
@@ -134,14 +198,16 @@ private static int write(OutputStream out, int width, byte[] bytes) throws IOExc
 	/**
 	 * Output an Attributes map. We sort the map keys.
 	 *
-	 * @param value the attributes
 	 * @param out the output stream
+	 * @param attributes the attributes
+	 * @param nice nice formatting or not
 	 * @throws IOException when something fails
 	 */
-	private static void writeAttributes(OutputStream out, Stream<Entry<Name, String>> attributes) throws IOException {
+	private static void writeAttributes(OutputStream out, Stream<Entry<Name, String>> attributes, boolean nice)
+		throws IOException {
 		for (Iterator<Entry<Name, String>> iterator = attributes.iterator(); iterator.hasNext();) {
 			Entry<Name, String> attribute = iterator.next();
-			writeEntry(out, attribute.getKey(), attribute.getValue());
+			writeEntry(out, attribute.getKey(), attribute.getValue(), nice);
 		}
 	}
 
@@ -170,4 +236,63 @@ private static Stream<Entry<Name, String>> sortedAttributes(Attributes attribute
 	private static Map<Name, String> coerce(Attributes attributes) {
 		return (Map) attributes;
 	}
+
+	/**
+	 * Parses delimited string and returns an array containing the tokens. This
+	 * parser obeys quotes, so the delimiter character will be ignored if it is
+	 * inside of a quote. This method assumes that the quote character is not
+	 * included in the set of delimiter characters.
+	 *
+	 * @param value the delimited string to parse.
+	 * @param delim the characters delimiting the tokens.
+	 * @return an array of string tokens or null if there were no tokens.
+	 **/
+	private static String[] parseDelimitedString(String value, String delim) {
+		if (value == null) {
+			value = "";
+		}
+
+		List<String> list = new ArrayList<>();
+
+		int CHAR = 1;
+		int DELIMITER = 2;
+		int STARTQUOTE = 4;
+		int ENDQUOTE = 8;
+
+		StringBuilder sb = new StringBuilder();
+
+		int expecting = (CHAR | DELIMITER | STARTQUOTE);
+
+		for (int i = 0; i < value.length(); i++) {
+			char c = value.charAt(i);
+
+			boolean isDelimiter = (delim.indexOf(c) >= 0);
+			boolean isQuote = (c == '"');
+
+			if (isDelimiter && ((expecting & DELIMITER) > 0)) {
+				list.add(sb.toString()
+					.trim());
+				sb.delete(0, sb.length());
+				expecting = (CHAR | DELIMITER | STARTQUOTE);
+			} else if (isQuote && ((expecting & STARTQUOTE) > 0)) {
+				sb.append(c);
+				expecting = CHAR | ENDQUOTE;
+			} else if (isQuote && ((expecting & ENDQUOTE) > 0)) {
+				sb.append(c);
+				expecting = (CHAR | STARTQUOTE | DELIMITER);
+			} else if ((expecting & CHAR) > 0) {
+				sb.append(c);
+			} else {
+				throw new IllegalArgumentException("Invalid delimited string: " + value);
+			}
+		}
+
+		String s = sb.toString()
+			.trim();
+		if (s.length() > 0) {
+			list.add(s);
+		}
+
+		return list.toArray(new String[list.size()]);
+	}
 }

aQute.libg/src/aQute/lib/manifest/package-info.java

@@ -1,4 +1,4 @@
-@Version("1.0.0")
+@Version("1.1.0")
 package aQute.lib.manifest;
 
 import org.osgi.annotation.versioning.Version;