Merge branch 'stable-5.3' into stable-5.4

* stable-5.3:
  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: I0e80612c8ddb934466105312f9107e91d581de0b

28 files changed, 109 insertions, 72 deletions

diff --git a/org.eclipse.jgit.ant.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.ant.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.ant.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.ant.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
diff --git a/org.eclipse.jgit.http.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.http.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.http.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.http.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
diff --git a/org.eclipse.jgit.junit/.settings/.api_filters b/org.eclipse.jgit.junit/.settings/.api_filters
new file mode 100644
index 0000000000..05665a3d15
--- /dev/null
+++ b/org.eclipse.jgit.junit/.settings/.api_filters
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<component id="org.eclipse.jgit.junit" version="2">
+    <resource path="src/org/eclipse/jgit/junit/Repeat.java" type="org.eclipse.jgit.junit.Repeat">
+        <filter id="1092616195">
+            <message_arguments>
+                <message_argument value="5.1.9"/>
+                <message_argument value="abortOnFailure()"/>
+            </message_arguments>
+        </filter>
+    </resource>
+</component>
diff --git a/org.eclipse.jgit.lfs.server.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.lfs.server.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.lfs.server.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.lfs.server.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
diff --git a/org.eclipse.jgit.lfs.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.lfs.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.lfs.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.lfs.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.target
index 36660ff3e6..941d4961d7 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.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-4.10" sequenceNumber="1566251637">
+<target name="jgit-4.10" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/2018-12/"/>
+      <repository location="https://download.eclipse.org/releases/2018-12/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.tpd
index 6beb42e33a..fad2e92005 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.10.tpd
@@ -3,6 +3,7 @@ target "jgit-4.10" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/2018-12/" {
+location "https://download.eclipse.org/releases/2018-12/" {
 	org.eclipse.osgi lazy
 }
+
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.target
index afa4b3da2c..4be2f466d2 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.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-4.11" sequenceNumber="1566251633">
+<target name="jgit-4.11" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/2019-03/"/>
+      <repository location="https://download.eclipse.org/releases/2019-03/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.tpd
index e09e8c387d..0864e7647f 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.11.tpd
@@ -3,6 +3,6 @@ target "jgit-4.11" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/2019-03/" {
+location "https://download.eclipse.org/releases/2019-03/" {
 	org.eclipse.osgi lazy
 }
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12-staging.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12-staging.tpd
deleted file mode 100644
index 43b64a0301..0000000000
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12-staging.tpd
+++ /dev/null
@@ -1,8 +0,0 @@
-target "jgit-4.12-staging" with source configurePhase
-
-include "projects/jetty-9.4.14.tpd"
-include "orbit/R20190602212107-2019-06.tpd"
-
-location "http://download.eclipse.org/staging/2019-06/" {
-	org.eclipse.osgi lazy
-}
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12-staging.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12.target
index 92c9a88366..34ffd455a6 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12-staging.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12.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-4.12-staging" sequenceNumber="1566251632">
+<target name="jgit-4.12" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/staging/2019-06/"/>
+      <repository location="https://download.eclipse.org/releases/2019-06/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12.tpd
new file mode 100644
index 0000000000..cff602607a
--- /dev/null
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.12.tpd
@@ -0,0 +1,8 @@
+target "jgit-4.12" with source configurePhase
+
+include "projects/jetty-9.4.14.tpd"
+include "orbit/R20190602212107-2019-06.tpd"
+
+location "https://download.eclipse.org/releases/2019-06/" {
+	org.eclipse.osgi lazy
+}
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.target
index 9724939f8a..489b01c58a 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.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-4.6" sequenceNumber="1566251641">
+<target name="jgit-4.6" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/neon/"/>
+      <repository location="https://download.eclipse.org/releases/neon/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.tpd
index 1a2c9a3a16..a43593f29b 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.6.tpd
@@ -3,6 +3,6 @@ target "jgit-4.6" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/neon/" {
+location "https://download.eclipse.org/releases/neon/" {
 	org.eclipse.osgi lazy
 }
\ No newline at end of file
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.target
index 6bd70e0160..627a83a755 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.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-4.7" sequenceNumber="1566251627">
+<target name="jgit-4.7" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/oxygen/"/>
+      <repository location="https://download.eclipse.org/releases/oxygen/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.tpd
index fc1b046edd..32835cabbf 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.7.tpd
@@ -3,6 +3,6 @@ target "jgit-4.7" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/oxygen/" {
+location "https://download.eclipse.org/releases/oxygen/" {
 	org.eclipse.osgi lazy
 }
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.target
index e33ece710a..dc45c7d16e 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.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-4.8" sequenceNumber="1566251616">
+<target name="jgit-4.8" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/photon/"/>
+      <repository location="https://download.eclipse.org/releases/photon/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.tpd
index a8f837e9ca..c11bc62fc2 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.8.tpd
@@ -3,6 +3,6 @@ target "jgit-4.8" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/photon/" {
+location "https://download.eclipse.org/releases/photon/" {
 	org.eclipse.osgi lazy
 }
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.target b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.target
index 9b3fe1b930..040c1d1274 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.target
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.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-4.9" sequenceNumber="1566251604">
+<target name="jgit-4.9" sequenceNumber="1638580694">
   <locations>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.jetty.client" version="9.4.14.v20181114"/>
@@ -20,7 +20,7 @@
       <unit id="org.eclipse.jetty.servlet.source" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util" version="9.4.14.v20181114"/>
       <unit id="org.eclipse.jetty.util.source" version="9.4.14.v20181114"/>
-      <repository id="jetty-9.4.14" location="http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114"/>
+      <repository id="jetty-9.4.14" location="https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114"/>
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.apache.ant" version="1.10.5.v20190526-1402"/>
@@ -86,7 +86,7 @@
     </location>
     <location includeMode="slicer" includeAllPlatforms="false" includeSource="true" includeConfigurePhase="true" type="InstallableUnit">
       <unit id="org.eclipse.osgi" version="0.0.0"/>
-      <repository location="http://download.eclipse.org/releases/2018-09/"/>
+      <repository location="https://download.eclipse.org/releases/2018-09/"/>
     </location>
   </locations>
 </target>
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.tpd
index f91f53eb8b..a2658b4382 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/jgit-4.9.tpd
@@ -3,6 +3,6 @@ target "jgit-4.9" with source configurePhase
 include "projects/jetty-9.4.14.tpd"
 include "orbit/R20190602212107-2019-06.tpd"
 
-location "http://download.eclipse.org/releases/2018-09/" {
+location "https://download.eclipse.org/releases/2018-09/" {
 	org.eclipse.osgi lazy
 }
\ No newline at end of file
diff --git a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/projects/jetty-9.4.14.tpd b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/projects/jetty-9.4.14.tpd
index 5372e77e5a..fb0963ef73 100644
--- a/org.eclipse.jgit.packaging/org.eclipse.jgit.target/projects/jetty-9.4.14.tpd
+++ b/org.eclipse.jgit.packaging/org.eclipse.jgit.target/projects/jetty-9.4.14.tpd
@@ -1,6 +1,6 @@
 target "jetty-9.4.14" with source configurePhase
 
-location jetty-9.4.14 "http://download.eclipse.org/jetty/updates/jetty-bundles-9.x/9.4.14.v20181114" {
+location jetty-9.4.14 "https://archive.eclipse.org/jetty/updates/jetty-bundles-9.x/jetty-bundles-9.x/9.4.14.v20181114" {
 	org.eclipse.jetty.client [9.4.14.v20181114,9.4.14.v20181114]
 	org.eclipse.jetty.client.source [9.4.14.v20181114,9.4.14.v20181114]
 	org.eclipse.jetty.continuation [9.4.14.v20181114,9.4.14.v20181114]
diff --git a/org.eclipse.jgit.packaging/pom.xml b/org.eclipse.jgit.packaging/pom.xml
index 1d6e6a0b81..5a90df0989 100644
--- a/org.eclipse.jgit.packaging/pom.xml
+++ b/org.eclipse.jgit.packaging/pom.xml
@@ -55,7 +55,7 @@
   <name>JGit Tycho Parent</name>
 
   <properties>
-    <tycho-version>1.4.0</tycho-version>
+    <tycho-version>1.7.0</tycho-version>
     <tycho-extras-version>${tycho-version}</tycho-extras-version>
     <target-platform>jgit-4.6</target-platform>
   </properties>
@@ -313,7 +313,7 @@
         <plugin>
           <groupId>org.eclipse.cbi.maven.plugins</groupId>
           <artifactId>eclipse-jarsigner-plugin</artifactId>
-          <version>1.1.5</version>
+          <version>1.3.2</version>
         </plugin>
         <plugin>
           <groupId>org.codehaus.mojo</groupId>
diff --git a/org.eclipse.jgit.pgm.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.pgm.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.pgm.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.pgm.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
diff --git a/org.eclipse.jgit.test/.settings/org.eclipse.jdt.core.prefs b/org.eclipse.jgit.test/.settings/org.eclipse.jdt.core.prefs
index 2ca78ff2d0..d4751b5352 100644
--- a/org.eclipse.jgit.test/.settings/org.eclipse.jdt.core.prefs
+++ b/org.eclipse.jgit.test/.settings/org.eclipse.jdt.core.prefs
@@ -52,7 +52,7 @@ org.eclipse.jdt.core.compiler.problem.missingJavadocComments=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocCommentsVisibility=protected
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagDescription=return_tag
-org.eclipse.jdt.core.compiler.problem.missingJavadocTags=error
+org.eclipse.jdt.core.compiler.problem.missingJavadocTags=ignore
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsMethodTypeParameters=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsOverriding=disabled
 org.eclipse.jdt.core.compiler.problem.missingJavadocTagsVisibility=private
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 8650ebfe29..e4ee53e0a1 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
@@ -218,6 +218,12 @@ public class FileSnapshot {
 	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
 	 */
@@ -253,9 +259,7 @@ public class FileSnapshot {
 	protected FileSnapshot(File file, boolean useConfig) {
 		this.file = file;
 		this.lastRead = Instant.now();
-		this.fileStoreAttributeCache = useConfig
-				? FS.getFileStoreAttributes(file.toPath().getParent())
-				: FALLBACK_FILESTORE_ATTRIBUTES;
+		this.useConfig = useConfig;
 		BasicFileAttributes fileAttributes = null;
 		try {
 			fileAttributes = FS.DETECTED.fileAttributes(file);
@@ -399,7 +403,7 @@ public class FileSnapshot {
 	 *             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);
@@ -436,6 +440,15 @@ public class FileSnapshot {
 		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() {
@@ -520,10 +533,10 @@ public class FileSnapshot {
 	}
 
 	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;
@@ -583,4 +596,13 @@ public class FileSnapshot {
 		}
 		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 7d31673566..8fa683f5ee 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
@@ -184,7 +184,7 @@ public class ObjectDirectoryPackParser extends PackParser {
 		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 f912dcbe1b..6cb8a19f81 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
@@ -1124,10 +1124,14 @@ public class RefDirectory extends RefDatabase {
 		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.
diff --git a/pom.xml b/pom.xml
index 7c47ca4ed0..26b1c1ae8a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -199,15 +199,14 @@
     <httpcore-version>4.4.10</httpcore-version>
     <slf4j-version>1.7.2</slf4j-version>
     <log4j-version>1.2.15</log4j-version>
-    <maven-javadoc-plugin-version>3.1.0</maven-javadoc-plugin-version>
-    <tycho-extras-version>1.4.0</tycho-extras-version>
+    <maven-javadoc-plugin-version>3.3.1</maven-javadoc-plugin-version>
+    <tycho-extras-version>1.7.0</tycho-extras-version>
     <gson-version>2.8.2</gson-version>
     <bouncycastle-version>1.61</bouncycastle-version>
-    <spotbugs-maven-plugin-version>3.1.12</spotbugs-maven-plugin-version>
-    <maven-project-info-reports-plugin-version>3.0.0</maven-project-info-reports-plugin-version>
-    <maven-jxr-plugin-version>3.0.0</maven-jxr-plugin-version>
-    <spotbugs-maven-plugin-version>3.1.12</spotbugs-maven-plugin-version>
-    <maven-surefire-plugin-version>3.0.0-M3</maven-surefire-plugin-version>
+    <maven-project-info-reports-plugin-version>3.1.2</maven-project-info-reports-plugin-version>
+    <maven-surefire-plugin-version>3.0.0-M5</maven-surefire-plugin-version>
+    <spotbugs-maven-plugin-version>4.3.0</spotbugs-maven-plugin-version>
+    <maven-surefire-plugin-version>3.0.0-M5</maven-surefire-plugin-version>
     <maven-surefire-report-plugin-version>${maven-surefire-plugin-version}</maven-surefire-report-plugin-version>
     <maven-compiler-plugin-version>3.8.1</maven-compiler-plugin-version>
 
@@ -241,7 +240,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-jar-plugin</artifactId>
-          <version>3.1.2</version>
+          <version>3.2.0</version>
           <configuration>
             <archive>
               <manifestEntries>
@@ -266,25 +265,25 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-shade-plugin</artifactId>
-          <version>3.2.1</version>
+          <version>3.2.4</version>
         </plugin>
 
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-antrun-plugin</artifactId>
-          <version>1.8</version>
+          <version>3.0.0</version>
         </plugin>
 
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-dependency-plugin</artifactId>
-          <version>3.1.1</version>
+          <version>3.2.0</version>
         </plugin>
 
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-source-plugin</artifactId>
-          <version>3.1.0</version>
+          <version>3.2.1</version>
         </plugin>
 
         <plugin>
@@ -307,7 +306,7 @@
         <plugin>
           <groupId>org.codehaus.mojo</groupId>
           <artifactId>build-helper-maven-plugin</artifactId>
-          <version>3.0.0</version>
+          <version>3.2.0</version>
         </plugin>
 
         <plugin>
@@ -330,7 +329,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-pmd-plugin</artifactId>
-          <version>3.12.0</version>
+          <version>3.15.0</version>
           <configuration>
             <sourceEncoding>utf-8</sourceEncoding>
             <minimumTokens>100</minimumTokens>
@@ -353,7 +352,7 @@
         <plugin>
           <groupId>org.eclipse.cbi.maven.plugins</groupId>
           <artifactId>eclipse-jarsigner-plugin</artifactId>
-          <version>1.1.5</version>
+          <version>1.3.2</version>
         </plugin>
         <plugin>
           <groupId>org.eclipse.tycho.extras</groupId>
@@ -368,12 +367,12 @@
         <plugin>
           <groupId>org.jacoco</groupId>
           <artifactId>jacoco-maven-plugin</artifactId>
-          <version>0.8.4</version>
+          <version>0.8.7</version>
         </plugin>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-site-plugin</artifactId>
-          <version>3.7.1</version>
+          <version>3.9.1</version>
           <dependencies>
             <dependency><!-- add support for ssh/scp -->
               <groupId>org.apache.maven.wagon</groupId>
@@ -415,7 +414,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-resources-plugin</artifactId>
-          <version>3.1.0</version>
+          <version>3.2.0</version>
         </plugin>
         <plugin>
           <groupId>org.springframework.boot</groupId>
@@ -429,7 +428,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-enforcer-plugin</artifactId>
-        <version>3.0.0-M2</version>
+        <version>3.0.0</version>
         <executions>
           <execution>
             <id>enforce-maven</id>