Merge branch 'stable-6.0'

* stable-6.0:
  Add missing @since tags
  Add missing @since tag
  Add missing @since tags
  Remove unused import in ApacheSshTest
  Update maven plugins
  Ignore missing javadoc in test bundles
  storage: file: De-duplicate File.exists()+File.isFile()
  RefDirectory.scanRef: Re-use file existence check done in snapshot creation
  FileSnapshot: Lazy load file store attributes cache
  Update eclipse-jarsigner-plugin to 1.3.2
  Fix p2 repository URLs

Change-Id: I694c011f322f9a19479ef67b9fc725371da7418f
diff --git a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/GitFilter.java b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/GitFilter.java
index 1769832..0957cc8 100644
--- a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/GitFilter.java
+++ b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/GitFilter.java
@@ -125,6 +125,7 @@ public void setUploadPackFactory(UploadPackFactory<HttpServletRequest> f) {
 	 *
 	 * @param h
 	 *            A custom error handler for git-upload-pack.
+	 * @since 5.6
 	 */
 	public void setUploadPackErrorHandler(UploadPackErrorHandler h) {
 		assertNotInitialized();
@@ -163,6 +164,7 @@ public void setReceivePackFactory(ReceivePackFactory<HttpServletRequest> f) {
 	 *
 	 * @param h
 	 *            A custom error handler for git-receive-pack.
+	 * @since 5.7
 	 */
 	public void setReceivePackErrorHandler(ReceivePackErrorHandler h) {
 		assertNotInitialized();
diff --git a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ReceivePackErrorHandler.java b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ReceivePackErrorHandler.java
index ee66cb1..a7ca4d0 100644
--- a/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ReceivePackErrorHandler.java
+++ b/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/ReceivePackErrorHandler.java
@@ -31,7 +31,7 @@
  * If a custom handler is not specified, JGit will use the default error
  * handler.
  *
- * @since 5.6
+ * @since 5.7
  */
 public interface ReceivePackErrorHandler {
 	/**
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
index 664615e..6bfe706 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
@@ -80,6 +80,7 @@ public String toString() {
 	 * @param userGitConfig
 	 *            set another user-level git config
 	 * @return the old user-level git config
+	 * @since 5.1.9
 	 */
 	public FileBasedConfig setUserGitConfig(FileBasedConfig userGitConfig) {
 		FileBasedConfig old = this.userGitConfig;
@@ -92,6 +93,7 @@ public FileBasedConfig setUserGitConfig(FileBasedConfig userGitConfig) {
 	 *
 	 * @param jgitConfig
 	 *            set the jgit configuration
+	 * @since 5.5
 	 */
 	public void setJGitConfig(FileBasedConfig jgitConfig) {
 		this.jgitConfig = jgitConfig;
@@ -103,6 +105,7 @@ public void setJGitConfig(FileBasedConfig jgitConfig) {
 	 * @param systemGitConfig
 	 *            the new system-level git config
 	 * @return the old system-level config
+	 * @since 5.1.9
 	 */
 	public FileBasedConfig setSystemGitConfig(FileBasedConfig systemGitConfig) {
 		FileBasedConfig old = this.systemGitConfig;
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepeatRule.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepeatRule.java
index 3db3ba9..adcc10c 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepeatRule.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepeatRule.java
@@ -60,6 +60,7 @@ public static class RepeatedTestException extends RuntimeException {
 		 *
 		 * @param message
 		 *            the error message
+		 * @since 5.1.9
 		 */
 		public RepeatedTestException(String message) {
 			super(message);
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepositoryTestCase.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepositoryTestCase.java
index 5622108..04988f6 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepositoryTestCase.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepositoryTestCase.java
@@ -340,6 +340,7 @@ public static String slashify(String str) {
 	 *         greater than then the lastmodification time of lastfile.
 	 * @throws InterruptedException
 	 * @throws IOException
+	 * @since 5.1.9
 	 */
 	public static Instant fsTick(File lastFile)
 			throws InterruptedException,
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java
index 4a4dc92..c8c56b2 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java
@@ -21,6 +21,8 @@
  * This class is used when it's required to load jgit classes in separate
  * classloader for each test class. It can be needed to isolate static field
  * initialization between separate tests.
+ *
+ * @since 5.5
  */
 public class SeparateClassloaderTestRunner extends BlockJUnit4ClassRunner {
 
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java
index 0232156..54e4a09 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java
@@ -339,6 +339,7 @@ public RevObject get(RevTree tree, String path)
 	 *            zero or more IDs of the commit's parents.
 	 * @return the ID of the new commit.
 	 * @throws Exception
+	 * @since 5.5
 	 */
 	public ObjectId unparsedCommit(ObjectId... parents) throws Exception {
 		return unparsedCommit(1, tree(), parents);
@@ -431,6 +432,7 @@ public RevCommit commit(final int secDelta, final RevTree tree,
 	 *            zero or more IDs of the commit's parents.
 	 * @return the ID of the new commit.
 	 * @throws Exception
+	 * @since 5.5
 	 */
 	public ObjectId unparsedCommit(final int secDelta, final RevTree tree,
 			final ObjectId... parents) throws Exception {
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/time/TimeUtil.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/time/TimeUtil.java
index 2ebb8e2..f93ac57 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/time/TimeUtil.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/time/TimeUtil.java
@@ -20,6 +20,8 @@
 
 /**
  * Utility methods for handling timestamps
+ *
+ * @since 5.1.9
  */
 public class TimeUtil {
 	/**
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.17.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.17.target
index 737cada..6d96033 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.17.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.17.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.17" sequenceNumber="1637746569">
+<target name="jgit-4.17" sequenceNumber="1638648728">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.18.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.18.target
index 55cadffa..cbe26bb 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.18.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.18.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.18" sequenceNumber="1637746569">
+<target name="jgit-4.18" sequenceNumber="1638648728">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.19.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.19.target
index 43fe4c8..ceff305 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.19.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.19.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.19-staging" sequenceNumber="1637746569">
+<target name="jgit-4.19-staging" sequenceNumber="1638648728">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.20.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.20.target
index aefa341..e2fed06 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.20.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.20.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.20" sequenceNumber="1637746569">
+<target name="jgit-4.20" sequenceNumber="1638648728">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.21.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.21.target
index 1b6cf26..4bd5546 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.21.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.21.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.21" sequenceNumber="1637746569">
+<target name="jgit-4.21" sequenceNumber="1638648728">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.22.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.22.target
index 7fd0032..98f44a8 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.22.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.22.target
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <?pde?>
 <!-- generated with https://github.com/eclipse-cbi/targetplatform-dsl -->
-<target name="jgit-4.22" sequenceNumber="1637746993">
+<target name="jgit-4.22" sequenceNumber="1638648736">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="jakarta.servlet-api" version="4.0.0"/>
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java
index 8c48cd9..5ab973f 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java
@@ -187,6 +187,12 @@ public static FileSnapshot save(Instant modified) {
 	private FileStoreAttributes fileStoreAttributeCache;
 
 	/**
+	 * if {@code true} read filesystem time resolution from configuration file
+	 * otherwise use fallback resolution
+	 */
+	private boolean useConfig;
+
+	/**
 	 * Object that uniquely identifies the given file, or {@code
 	 * null} if a file key is not available
 	 */
@@ -222,9 +228,7 @@ protected FileSnapshot(File file) {
 	protected FileSnapshot(File file, boolean useConfig) {
 		this.file = file;
 		this.lastRead = Instant.now();
-		this.fileStoreAttributeCache = useConfig
-				? FS.getFileStoreAttributes(file.toPath())
-				: FALLBACK_FILESTORE_ATTRIBUTES;
+		this.useConfig = useConfig;
 		BasicFileAttributes fileAttributes = null;
 		try {
 			fileAttributes = FS.DETECTED.fileAttributes(file);
@@ -379,7 +383,7 @@ public void setClean(FileSnapshot other) {
 	 *             if sleep was interrupted
 	 */
 	public void waitUntilNotRacy() throws InterruptedException {
-		long timestampResolution = fileStoreAttributeCache
+		long timestampResolution = fileStoreAttributeCache()
 				.getFsTimestampResolution().toNanos();
 		while (isRacyClean(Instant.now())) {
 			TimeUnit.NANOSECONDS.sleep(timestampResolution);
@@ -416,6 +420,15 @@ public boolean equals(Object obj) {
 		return equals(other);
 	}
 
+	/**
+	 * Check if the file exists
+	 *
+	 * @return true if the file exists
+	 */
+	public boolean fileExists() {
+		return !MISSING_FILEKEY.equals(this.fileKey);
+	}
+
 	/** {@inheritDoc} */
 	@Override
 	public int hashCode() {
@@ -500,10 +513,10 @@ private boolean isRacyClean(Instant read) {
 	}
 
 	private long getEffectiveRacyThreshold() {
-		long timestampResolution = fileStoreAttributeCache
+		long timestampResolution = fileStoreAttributeCache()
 				.getFsTimestampResolution().toNanos();
-		long minRacyInterval = fileStoreAttributeCache.getMinimalRacyInterval()
-				.toNanos();
+		long minRacyInterval = fileStoreAttributeCache()
+				.getMinimalRacyInterval().toNanos();
 		long max = Math.max(timestampResolution, minRacyInterval);
 		// safety margin: factor 2.5 below 100ms otherwise 1.25
 		return max < 100_000_000L ? max * 5 / 2 : max * 5 / 4;
@@ -563,4 +576,13 @@ private boolean isSizeChanged(long currSize) {
 		}
 		return changed;
 	}
+
+	private FileStoreAttributes fileStoreAttributeCache() {
+		if (fileStoreAttributeCache == null) {
+			fileStoreAttributeCache = useConfig
+					? FS.getFileStoreAttributes(file.toPath().getParent())
+					: FALLBACK_FILESTORE_ATTRIBUTES;
+		}
+		return fileStoreAttributeCache;
+	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectoryPackParser.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectoryPackParser.java
index 1c23ff2..55b2646 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectoryPackParser.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectoryPackParser.java
@@ -153,7 +153,7 @@ public long getPackSize() {
 		String p = pack.getAbsolutePath();
 		String i = p.substring(0, p.length() - ".pack".length()) + ".idx"; //$NON-NLS-1$ //$NON-NLS-2$
 		File idx = new File(i);
-		if (idx.exists() && idx.isFile())
+		if (idx.isFile())
 			size += idx.length();
 		return size;
 	}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java
index 17a9100..2167262 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java
@@ -1092,10 +1092,14 @@ LooseRef scanRef(LooseRef ref, String name) throws IOException {
 		final int limit = 4096;
 		final byte[] buf;
 		FileSnapshot otherSnapshot = FileSnapshot.save(path);
+		if (!otherSnapshot.fileExists()) {
+			return null;
+		}
+
 		try {
 			buf = IO.readSome(path, limit);
 		} catch (FileNotFoundException noFile) {
-			if (path.exists() && path.isFile()) {
+			if (path.isFile()) {
 				throw noFile;
 			}
 			return null; // doesn't exist or no file; not a reference.