Introduce ParseExceptions for GitDateParser

Instead of just returning null when something was not parseable we
should throw a real ParseException. This allows us to distinguish
between specifications which are unparseable and those which represent
no date (e.g. "never")

Change-Id: Ib3c1aa64b65ed0e0270791a365f2fa72ab78a3f4

3 files changed, 36 insertions, 17 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
index ec3c37d8ca..d70481450c 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
@@ -115,6 +115,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String cannotMoveIndexTo;
 	/***/ public String cannotMovePackTo;
 	/***/ public String cannotOpenService;
+	/***/ public String cannotParseDate;
 	/***/ public String cannotParseGitURIish;
 	/***/ public String cannotPullOnARepoWithState;
 	/***/ public String cannotRead;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/GC.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/GC.java
index 28dc5447bf..2e7208cd80 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/GC.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/GC.java
@@ -50,6 +50,7 @@ import java.io.OutputStream;
 import java.nio.channels.Channels;
 import java.nio.channels.FileChannel;
 import java.text.MessageFormat;
+import java.text.ParseException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -143,8 +144,11 @@ public class GC {
 	 *
 	 * @return the collection of {@link PackFile}'s which are newly created
 	 * @throws IOException
+	 * @throws ParseException
+	 *             If the configuration parameter "gc.pruneexpire" couldn't be
+	 *             parsed
 	 */
-	public Collection<PackFile> gc() throws IOException {
+	public Collection<PackFile> gc() throws IOException, ParseException {
 		pm.start(6 /* tasks */);
 		packRefs();
 		// TODO: implement reflog_expire(pm, repo);
@@ -256,9 +260,12 @@ public class GC {
 	 *            a set of objects which should explicitly not be pruned
 	 *
 	 * @throws IOException
+	 * @throws ParseException
+	 *             If the configuration parameter "gc.pruneexpire" couldn't be
+	 *             parsed
 	 */
-	public void prune(Set<ObjectId> objectsToKeep)
-			throws IOException {
+	public void prune(Set<ObjectId> objectsToKeep) throws IOException,
+			ParseException {
 		long expireDate = Long.MAX_VALUE;
 
 		if (expire == null && expireAgeMillis == -1) {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateParser.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateParser.java
index 04ef553b05..dc5c7fa568 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateParser.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateParser.java
@@ -42,6 +42,7 @@
  */
 package org.eclipse.jgit.util;
 
+import java.text.MessageFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Calendar;
@@ -50,6 +51,8 @@ import java.util.GregorianCalendar;
 import java.util.HashMap;
 import java.util.Map;
 
+import org.eclipse.jgit.internal.JGitText;
+
 /**
  * Parses strings with time and date specifications into {@link Date}.
  *
@@ -135,32 +138,40 @@ public class GitDateParser {
 	 *            parser often but wants a consistent starting point for calls.<br>
 	 *            If set to <code>null</code> then the current time will be used
 	 *            instead.
-	 * @return the parsed {@link Date} or <code>null</code> if this string was
-	 *         not parseable.
+	 * @return the parsed {@link Date}
+	 * @throws ParseException
+	 *             if the given dateStr was not recognized
 	 */
-	public static Date parse(String dateStr, Calendar now) {
+	public static Date parse(String dateStr, Calendar now)
+			throws ParseException {
 		dateStr = dateStr.trim();
 		Date ret;
 		ret = parse_relative(dateStr, now);
 		if (ret != null)
 			return ret;
 		for (ParseableSimpleDateFormat f : ParseableSimpleDateFormat.values()) {
-			ret = parse_simple(dateStr, f);
-			if (ret != null)
-				return ret;
+			try {
+				return parse_simple(dateStr, f);
+			} catch (ParseException e) {
+				// simply proceed with the next parser
+			}
 		}
-		return null;
+		ParseableSimpleDateFormat[] values = ParseableSimpleDateFormat.values();
+		StringBuilder allFormats = new StringBuilder("\"")
+				.append(values[0].formatStr);
+		for (int i = 1; i < values.length; i++)
+			allFormats.append("\", \"").append(values[i].formatStr);
+		allFormats.append("\"");
+		throw new ParseException(MessageFormat.format(
+				JGitText.get().cannotParseDate, dateStr, allFormats.toString()), 0);
 	}
 
 	// tries to parse a string with the formats supported by SimpleDateFormat
-	private static Date parse_simple(String dateStr, ParseableSimpleDateFormat f) {
+	private static Date parse_simple(String dateStr, ParseableSimpleDateFormat f)
+			throws ParseException {
 		SimpleDateFormat dateFormat = getDateFormat(f);
-		try {
-			dateFormat.setLenient(false);
-			return dateFormat.parse(dateStr);
-		} catch (ParseException e) {
-			return null;
-		}
+		dateFormat.setLenient(false);
+		return dateFormat.parse(dateStr);
 	}
 
 	// tries to parse a string with a relative time specification