Build with JDK-9 only (#1097)

* Use --release 8 option from JDK 9 javac

* Remove matrix and special java options from Travis CI
  The JUnit 5 build requires JDK-9 or higher.
  The JUnit 5 runtime environment needs to be Java 8 or higher.
  Travis CI now sets "-Xmx" by default.

* Switch Javadoc step to use JDK 9

* Switch AsciiDoc step to use JDK 9 w/o PDF backend
  See jruby/jruby#4805

* Fix Clover instrumentation

* Add custom AppVeyor script to install JDK-9

* Add JDK9-compatible Javadoc stylesheet

* Fix Javadoc @value tag usages

.appveyor.yml

@@ -0,0 +1,10 @@
+build: off
+
+install:
+  - cinst jdk9 -params 'installdir=C:\\jdk9'
+  - SET JAVA_HOME=C:\jdk9
+  - SET PATH=C:\jdk9\bin;%PATH%
+
+test_script:
+  - gradlew -version
+  - gradlew build --stacktrace

.travis.yml

@@ -1,4 +1,6 @@
 language: java
+jdk: oraclejdk9
+
 sudo: false
 dist: trusty
 
@@ -7,14 +9,6 @@ branches:
   except:
     - /^r\d.*$/
 
-env:
-  - _JAVA_OPTIONS='-Xmx500m'
-
-matrix:
-  include:
-    - jdk: oraclejdk8 # JDK 1.8.0_131-b11 or newer
-    - jdk: oraclejdk9 # JDK 9+175 or newer
-
 # Don't let Travis CI execute './gradlew assemble' by default
 install:
 # Display Gradle, Groovy, JVM and other versions

Jenkinsfile

@@ -29,9 +29,6 @@ pipeline {
       }
     }
     stage('Aggregate Javadoc') {
-      tools {
-        jdk 'Oracle JDK 8 (latest)' // Use JDK 8 because of custom stylesheet
-      }
       steps {
         sh './gradlew --no-daemon aggregateJavadocs'
       }
@@ -46,9 +43,6 @@ pipeline {
       }
     }
     stage('Generate User Guide') {
-      tools {
-        jdk 'Oracle JDK 8 (latest)' // Use JDK 8 because AsciiDoctor has problems on JDK 9
-      }
       steps {
         sh './gradlew --no-daemon asciidoctor'
       }

build.gradle

@@ -126,13 +126,14 @@ allprojects { subproj ->
 	}
 
 	tasks.withType(JavaCompile) {
-		sourceCompatibility = rootProject.sourceCompatibility
-		targetCompatibility = rootProject.targetCompatibility
+		sourceCompatibility = rootProject.javacRelease // needed by clover
+		targetCompatibility = rootProject.javacRelease // needed by clover/asm
 		options.encoding = 'UTF-8'
 	}
 
-	// See: http://docs.oracle.com/javase/8/docs/technotes/tools/windows/javac.html#BHCJCABJ
+	// See: https://docs.oracle.com/javase/9/tools/javac.htm#JSWOR627
 	compileJava.options*.compilerArgs = [
+		'--release', rootProject.javacRelease,
 		'-Xlint:cast',
 		'-Xlint:classfile',
 		'-Xlint:deprecation',
@@ -154,8 +155,9 @@ allprojects { subproj ->
 		'-Werror'
 	]
 
-	// See: http://docs.oracle.com/javase/8/docs/technotes/tools/windows/javac.html#BHCJCABJ
+	// See: https://docs.oracle.com/javase/9/tools/javac.htm#JSWOR627
 	compileTestJava.options*.compilerArgs = [
+		'--release', rootProject.javacRelease,
 		'-Xlint:cast',
 		'-Xlint:classfile',
 		'-Xlint:deprecation',
@@ -218,6 +220,7 @@ allprojects { subproj ->
 					initstring: cloverInitstring,
 					recordTestResults: false,
 					destdir: instrumentedJavaSourcesDir,
+					encoding: 'UTF-8',
 					source: compileJava.sourceCompatibility) {
 					sourceSets.main.allJava.addToAntBuilder(ant, 'fileset', FileCollection.AntType.FileSet)
 				}

documentation/documentation.gradle

@@ -80,7 +80,7 @@ asciidoctor {
 	separateOutputDirs false
 	sources { include 'index.adoc' }
 
-	backends 'html5', 'pdf' // , 'epub3'
+	backends 'html5' // , 'pdf' // , 'epub3'
 
 	attributes	'jupiter-version': project.property('version'),
 				'platform-version': project.property('platformVersion'),

gradle.properties

@@ -7,8 +7,11 @@ platformVersion     = 1.1.0-SNAPSHOT
 vintageGroup        = org.junit.vintage
 vintageVersion      = 4.12.2-SNAPSHOT
 
-sourceCompatibility = 1.8
-targetCompatibility = 1.8
+# --release release
+# Compiles against the public, supported and documented API for a specific VM version.
+# Supported release targets are 6, 7, 8, and 9.
+# Note that if --release is added then -target and -source are ignored.
+javacRelease = 8
 
 apiGuardianVersion  = 1.0.0
 assertJVersion      = 3.8.0

junit-jupiter-api/src/main/java/org/junit/jupiter/api/RepeatedTest.java

@@ -76,7 +76,7 @@
 	String TOTAL_REPETITIONS_PLACEHOLDER = "{totalRepetitions}";
 
 	/**
-	 * <em>Short</em> display name pattern for a repeated test: {@value #SHORT_DISPLAY_NAME}
+	 * <em>Short</em> display name pattern for a repeated test: {@value}
 	 *
 	 * @see #CURRENT_REPETITION_PLACEHOLDER
 	 * @see #TOTAL_REPETITIONS_PLACEHOLDER
@@ -85,7 +85,7 @@
 	String SHORT_DISPLAY_NAME = "repetition " + CURRENT_REPETITION_PLACEHOLDER + " of " + TOTAL_REPETITIONS_PLACEHOLDER;
 
 	/**
-	 * <em>Long</em> display name pattern for a repeated test: {@value #LONG_DISPLAY_NAME}
+	 * <em>Long</em> display name pattern for a repeated test: {@value}
 	 *
 	 * @see #DISPLAY_NAME_PLACEHOLDER
 	 * @see #SHORT_DISPLAY_NAME

junit-platform-engine/src/main/java/org/junit/platform/engine/discovery/ClassNameFilter.java

@@ -27,8 +27,9 @@ public interface ClassNameFilter extends DiscoveryFilter<String> {
 	/**
 	 * Standard include pattern in the form of a regular expression that is
 	 * used to match against fully qualified class names:
-	 * {@value #STANDARD_INCLUDE_PATTERN} which matches against class names
-	 * ending in {@code Test} or {@code Tests} (in any package).
+	 * {@value org.junit.platform.engine.discovery.ClassNameFilter#STANDARD_INCLUDE_PATTERN}
+	 * which matches against class names ending in {@code Test} or
+	 * {@code Tests} (in any package).
 	 */
 	String STANDARD_INCLUDE_PATTERN = "^.*Tests?$";