Merge pull request #388 from paketo-buildpacks/gh-136

Only contribute active-processor-count helper for Java versions < 17

build.go

@@ -272,7 +272,7 @@ func (b *Build) contributeNIK(jdkDep libpak.BuildpackDependency, nativeDep libpa
 }
 
 func (b *Build) contributeHelpers(context libcnb.BuildContext, depJRE libpak.BuildpackDependency) {
-	helpers := []string{"active-processor-count", "java-opts", "jvm-heap", "link-local-dns", "memory-calculator",
+	helpers := []string{"java-opts", "jvm-heap", "link-local-dns", "memory-calculator",
 		"security-providers-configurer", "jmx", "jfr", "openssl-certificate-loader"}
 
 	if IsBeforeJava9(depJRE.Version) {
@@ -283,6 +283,11 @@ func (b *Build) contributeHelpers(context libcnb.BuildContext, depJRE libpak.Bui
 		helpers = append(helpers, "debug-9")
 		helpers = append(helpers, "nmt")
 	}
+
+	if IsBeforeJava17(depJRE.Version) {
+		helpers = append(helpers, "active-processor-count")
+	}
+
 	found := false
 	for _, custom := range b.CustomHelpers {
 		if found {

build_test.go

@@ -52,6 +52,10 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		})
 	)
 
+	it.Before(func() {
+		t.Setenv("BP_ARCH", "amd64")
+	})
+
 	it("contributes JDK", func() {
 		ctx.Plan.Entries = append(ctx.Plan.Entries, libcnb.BuildpackPlanEntry{Name: "jdk"})
 		ctx.Buildpack.Metadata = map[string]interface{}{
@@ -123,7 +127,6 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		Expect(err).NotTo(HaveOccurred())
 
 		Expect(result.Layers[1].(libpak.HelperLayerContributor).Names).To(Equal([]string{
-			"active-processor-count",
 			"java-opts",
 			"jvm-heap",
 			"link-local-dns",
@@ -134,6 +137,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 			"openssl-certificate-loader",
 			"security-providers-classpath-8",
 			"debug-8",
+			"active-processor-count",
 		}))
 	})
 
@@ -154,7 +158,70 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		Expect(err).NotTo(HaveOccurred())
 
 		Expect(result.Layers[1].(libpak.HelperLayerContributor).Names).To(Equal([]string{
+			"java-opts",
+			"jvm-heap",
+			"link-local-dns",
+			"memory-calculator",
+			"security-providers-configurer",
+			"jmx",
+			"jfr",
+			"openssl-certificate-loader",
+			"security-providers-classpath-9",
+			"debug-9",
+			"nmt",
+			"active-processor-count",
+		}))
+	})
+
+	it("contributes active-processor-count before Java 17", func() {
+		ctx.Plan.Entries = append(ctx.Plan.Entries, libcnb.BuildpackPlanEntry{Name: "jre", Metadata: LaunchContribution})
+		ctx.Buildpack.Metadata = map[string]interface{}{
+			"dependencies": []map[string]interface{}{
+				{
+					"id":      "jre",
+					"version": "11.0.0",
+					"stacks":  []interface{}{"test-stack-id"},
+				},
+			},
+		}
+		ctx.StackID = "test-stack-id"
+
+		result, err := libjvm.NewBuild(bard.NewLogger(io.Discard)).Build(ctx)
+		Expect(err).NotTo(HaveOccurred())
+
+		Expect(result.Layers[1].(libpak.HelperLayerContributor).Names).To(Equal([]string{
+			"java-opts",
+			"jvm-heap",
+			"link-local-dns",
+			"memory-calculator",
+			"security-providers-configurer",
+			"jmx",
+			"jfr",
+			"openssl-certificate-loader",
+			"security-providers-classpath-9",
+			"debug-9",
+			"nmt",
 			"active-processor-count",
+		}))
+	})
+
+	it("does not contribute active-processor-count with Java 17 and later", func() {
+		ctx.Plan.Entries = append(ctx.Plan.Entries, libcnb.BuildpackPlanEntry{Name: "jre", Metadata: LaunchContribution})
+		ctx.Buildpack.Metadata = map[string]interface{}{
+			"dependencies": []map[string]interface{}{
+				{
+					"id":      "jre",
+					"version": "17.0.0",
+					"stacks":  []interface{}{"test-stack-id"},
+				},
+			},
+		}
+		ctx.StackID = "test-stack-id"
+
+		result, err := libjvm.NewBuild(bard.NewLogger(io.Discard)).Build(ctx)
+		Expect(err).NotTo(HaveOccurred())
+
+		Expect(result.Layers[1].(libpak.HelperLayerContributor).Names).To(Equal([]string{
 			"java-opts",
 			"jvm-heap",
 			"link-local-dns",

versions.go

@@ -21,6 +21,7 @@ import (
 )
 
 var Java9, _ = semver.NewVersion("9")
+var Java17, _ = semver.NewVersion("17")
 var Java18, _ = semver.NewVersion("18")
 
 func IsBeforeJava9(candidate string) bool {
@@ -32,6 +33,15 @@ func IsBeforeJava9(candidate string) bool {
 	return v.LessThan(Java9)
 }
 
+func IsBeforeJava17(candidate string) bool {
+	v, err := semver.NewVersion(candidate)
+	if err != nil {
+		return false
+	}
+
+	return v.LessThan(Java17)
+}
+
 func IsBeforeJava18(candidate string) bool {
 	v, err := semver.NewVersion(candidate)
 	if err != nil {

versions_test.go

@@ -37,4 +37,17 @@ func testVersions(t *testing.T, context spec.G, it spec.S) {
 		Expect(libjvm.IsBeforeJava9("")).To(BeFalse())
 	})
 
+	it("determins whether a version is before Java 18", func() {
+		Expect(libjvm.IsBeforeJava18("17.0.0")).To(BeTrue())
+		Expect(libjvm.IsBeforeJava18("18.0.0")).To(BeFalse())
+		Expect(libjvm.IsBeforeJava18("19.0.0")).To(BeFalse())
+		Expect(libjvm.IsBeforeJava18("")).To(BeFalse())
+	})
+
+	it("determines whether a version is before Java 17", func() {
+		Expect(libjvm.IsBeforeJava17("16.0.0")).To(BeTrue())
+		Expect(libjvm.IsBeforeJava17("17.0.0")).To(BeFalse())
+		Expect(libjvm.IsBeforeJava17("18.0.0")).To(BeFalse())
+		Expect(libjvm.IsBeforeJava17("")).To(BeFalse())
+	})
 }