Merge branch 'stable-5.4'

* stable-5.4: (82 commits)
  Export all packages of o.e.j.ant and o.e.j.archive bundles
  Do not require test bundles to export all packages
  Fix API problem filters
  Increase severity of AmbiguousMethodReference to ERROR
  [error prone] suppress AmbiguousMethodReference in AnyLongObjectId
  [error prone] fix ReferenceEquality warning in CommitBuilder
  [error prone] suppress NonAtomicVolatileUpdate warning in SimpleLruCache
  [error prone] fix ReferenceEquality warning in CommitGraphPane#authorFor
  [error prone] fix ReferenceEquality warning in RevWalk#isMergedInto
  [error prone] fix ReferenceEquality warning in RefUpdate#updateImpl
  [error prone] fix ReferenceEquality warning in static equals methods
  [error prone] suppress AmbiguousMethodReference in AnyObjectId
  [error prone] fix "FutureReturnValueIgnored" error in FS
  Fix formatting and add missing braces in Repository#stripWorkDir
  Repository: fix reference comparison of Files
  MergeAlgorithm: Suppress Error Prone warning about reference equality
  Fix NarrowingCompoundAssignment warnings from Error Prone
  FS_POSIX: handle Files.getFileStore() failures
  Fix OpenSshConfigTest#config
  FileSnapshot: fix bug with timestamp thresholding
  In LockFile#waitForStatChange wait in units of file time resolution
  Cache FileStoreAttributeCache per directory
  Fix FileSnapshot#save(long) and FileSnapshot#save(Instant)
  Persist minimal racy threshold and allow manual configuration
  Measure minimum racy interval to auto-configure FileSnapshot
  Reuse FileUtils to recursively delete files created by tests
  Fix FileAttributeCache.toString()
  Add test for racy git detection in FileSnapshot
  Repeat RefDirectoryTest.testGetRef_DiscoversModifiedLoose 100 times
  Fix org.eclipse.jdt.core.prefs of org.eclipse.jgit.junit
  Add missing javadoc in org.eclipse.jgit.junit
  Enhance RepeatRule to report number of failures at the end
  Fix FileSnapshotTests for filesystem with high timestamp resolution
  Retry deleting test files in FileBasedConfigTest
  Measure filesystem timestamp resolution already in test setup
  Refactor FileSnapshotTest to use NIO APIs
  Measure stored timestamp resolution instead of time to touch file
  Handle CancellationException in FileStoreAttributeCache
  Fix FileSnapshot#saveNoConfig
  Use Instant for smudge time in DirCache and DirCacheEntry
  Use Instant instead of milliseconds for filesystem timestamp handling
  Workaround SecurityException in FS#getFsTimestampResolution
  Fix NPE in FS$FileStoreAttributeCache.getFsTimestampResolution
  FS: ignore AccessDeniedException when measuring timestamp resolution
  Add debug trace for FileSnapshot
  Use FileChannel.open to touch file and set mtime to now
  Persist filesystem timestamp resolution and allow manual configuration
  Increase bazel timeout for long running tests
  Bazel: Fix lint warning flagged by buildifier
  Update bazlets to latest version
  Bazel: Add missing dependencies for ArchiveCommandTest
  Bazel: Remove FileTreeIteratorWithTimeControl from BUILD file
  Add support for nanoseconds and microseconds for Config#getTimeUnit
  Optionally measure filesystem timestamp resolution asynchronously
  Delete unused FileTreeIteratorWithTimeControl
  FileSnapshot#equals: consider UNKNOWN_SIZE
  Timeout measuring file timestamp resolution after 2 seconds
  Fix RacyGitTests#testRacyGitDetection
  GlobalBundleCache: Fix ClassNewInstance warning from Error Prone
  IncorrectObjectTypeException: Fix typos in constructors' Javadoc
  Change RacyGitTests to create a racy git situation in a stable way
  Deprecate Constants.CHARACTER_ENCODING in favor of StandardCharsets.UTF_8
  Fix non-deterministic hash of archives created by ArchiveCommand
  Update Maven plugins ecj, plexus, error-prone
  Update Maven plugins and cleanup Maven warnings
  Make inner classes static where possible
  Error Prone: Increase severity of NonOverridingEquals to ERROR
  Error Prone: Increase severity of ImmutableEnumChecker to ERROR
  GitDateParser#ParseableSimpleDateFormat: Make formatStr private final
  BatchRefUpdateTest: Suppress ImmutableEnumChecker warning
  PacketLineIn: Suppress comparison warnings for END and DELIM
  FileSnapshot#toString: Suppress ReferenceEquality warnings
  Blame: Suppress ReferenceEquality warning for RevCommit instances
  Fix API problem filters
  pgm: add missing optional dependency to org.tukaani:xz
  NetscapeCookieFile: Make hash static and group overloaded write
  NetscapeCookieFile: Javadoc fixes
  Config: Handle reference-equality warning (and empty javadoc)
  Error Prone: Increase severity of ShortCircuitBoolean to ERROR
  ObjectWalk: Prefer boolean operators over logical operators in comparisons
  BasePackFetchConnection: Prefer boolean operators over logical operators in comparisons
  PackWriter: Prefer boolean operators over logical operators in comparisons

Change-Id: I825fd55bcb5345fb7afe066bf54ca50325f40acb
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

2 files changed, 12 insertions, 5 deletions

diff --git a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/FileSender.java b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/FileSender.java
index 05510a05b0..946fb15a3d 100644
--- a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/FileSender.java
+++ b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/FileSender.java
@@ -58,12 +58,14 @@ import java.io.IOException;
 import java.io.OutputStream;
 import java.io.RandomAccessFile;
 import java.text.MessageFormat;
+import java.time.Instant;
 import java.util.Enumeration;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.util.FS;
 
 /**
  * Dumps a file over HTTP GET (or its information via HEAD).
@@ -76,7 +78,7 @@ final class FileSender {
 
 	private final RandomAccessFile source;
 
-	private final long lastModified;
+	private final Instant lastModified;
 
 	private final long fileLen;
 
@@ -89,7 +91,7 @@ final class FileSender {
 		this.source = new RandomAccessFile(path, "r");
 
 		try {
-			this.lastModified = path.lastModified();
+			this.lastModified = FS.DETECTED.lastModifiedInstant(path);
 			this.fileLen = source.getChannel().size();
 			this.end = fileLen;
 		} catch (IOException e) {
@@ -114,7 +116,7 @@ final class FileSender {
 		}
 	}
 
-	long getLastModified() {
+	Instant getLastModified() {
 		return lastModified;
 	}
 
diff --git a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ObjectFileServlet.java b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ObjectFileServlet.java
index 62f075c73c..5a27be6430 100644
--- a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ObjectFileServlet.java
+++ b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ObjectFileServlet.java
@@ -54,6 +54,7 @@ import static org.eclipse.jgit.util.HttpSupport.HDR_LAST_MODIFIED;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.time.Instant;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
@@ -76,7 +77,9 @@ abstract class ObjectFileServlet extends HttpServlet {
 
 		@Override
 		String etag(FileSender sender) throws IOException {
-			return Long.toHexString(sender.getLastModified());
+			Instant lastModified = sender.getLastModified();
+			return Long.toHexString(lastModified.getEpochSecond())
+					+ Long.toHexString(lastModified.getNano());
 		}
 	}
 
@@ -145,7 +148,9 @@ abstract class ObjectFileServlet extends HttpServlet {
 
 		try {
 			final String etag = etag(sender);
-			final long lastModified = (sender.getLastModified() / 1000) * 1000;
+			// HTTP header Last-Modified header has a resolution of 1 sec, see
+			// https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.29
+			final long lastModified = sender.getLastModified().getEpochSecond();
 
 			String ifNoneMatch = req.getHeader(HDR_IF_NONE_MATCH);
 			if (etag != null && etag.equals(ifNoneMatch)) {