Add classpath fragment property to skip proto generation.

This must always be true for updatable apexes, but is not necessary
for non-updatable apexes like com.android.i18n.

In a follow up this will be used to figure out whether apex boot jars
should be bundled into platform_bootclasspath.

Bug: 191127295
Test: atest CtsClasspathsTestCases derive_classpath_test
Change-Id: Ib7dc5b057cb24955222fb97f3ff9da079f30ed77
diff --git a/apex/apex.go b/apex/apex.go
index 9e714ab..1965ec2 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -1756,7 +1756,9 @@
 						ctx.PropertyErrorf("systemserverclasspath_fragments", "%q is not a systemserverclasspath_fragment module", depName)
 						return false
 					}
-					filesInfo = append(filesInfo, apexClasspathFragmentProtoFile(ctx, child))
+					if af := apexClasspathFragmentProtoFile(ctx, child); af != nil {
+						filesInfo = append(filesInfo, *af)
+					}
 					return true
 				}
 			case javaLibTag:
@@ -2159,17 +2161,23 @@
 	}
 
 	// Add classpaths.proto config.
-	filesToAdd = append(filesToAdd, apexClasspathFragmentProtoFile(ctx, module))
+	if af := apexClasspathFragmentProtoFile(ctx, module); af != nil {
+		filesToAdd = append(filesToAdd, *af)
+	}
 
 	return filesToAdd
 }
 
-// apexClasspathFragmentProtoFile returns apexFile structure defining the classpath.proto config that
-// the module contributes to the apex.
-func apexClasspathFragmentProtoFile(ctx android.ModuleContext, module blueprint.Module) apexFile {
-	fragmentInfo := ctx.OtherModuleProvider(module, java.ClasspathFragmentProtoContentInfoProvider).(java.ClasspathFragmentProtoContentInfo)
-	classpathProtoOutput := fragmentInfo.ClasspathFragmentProtoOutput
-	return newApexFile(ctx, classpathProtoOutput, classpathProtoOutput.Base(), fragmentInfo.ClasspathFragmentProtoInstallDir.Rel(), etc, nil)
+// apexClasspathFragmentProtoFile returns *apexFile structure defining the classpath.proto config that
+// the module contributes to the apex; or nil if the proto config was not generated.
+func apexClasspathFragmentProtoFile(ctx android.ModuleContext, module blueprint.Module) *apexFile {
+	info := ctx.OtherModuleProvider(module, java.ClasspathFragmentProtoContentInfoProvider).(java.ClasspathFragmentProtoContentInfo)
+	if !info.ClasspathFragmentProtoGenerated {
+		return nil
+	}
+	classpathProtoOutput := info.ClasspathFragmentProtoOutput
+	af := newApexFile(ctx, classpathProtoOutput, classpathProtoOutput.Base(), info.ClasspathFragmentProtoInstallDir.Rel(), etc, nil)
+	return &af
 }
 
 // apexFileForBootclasspathFragmentContentModule creates an apexFile for a bootclasspath_fragment
@@ -2355,16 +2363,30 @@
 	})
 }
 
-// Enforce that Java deps of the apex are using stable SDKs to compile
+// checkUpdatable enforces APEX and its transitive dep properties to have desired values for updatable APEXes.
 func (a *apexBundle) checkUpdatable(ctx android.ModuleContext) {
 	if a.Updatable() {
 		if String(a.properties.Min_sdk_version) == "" {
 			ctx.PropertyErrorf("updatable", "updatable APEXes should set min_sdk_version as well")
 		}
 		a.checkJavaStableSdkVersion(ctx)
+		a.checkClasspathFragments(ctx)
 	}
 }
 
+// checkClasspathFragments enforces that all classpath fragments in deps generate classpaths.proto config.
+func (a *apexBundle) checkClasspathFragments(ctx android.ModuleContext) {
+	ctx.VisitDirectDeps(func(module android.Module) {
+		if tag := ctx.OtherModuleDependencyTag(module); tag == bcpfTag || tag == sscpfTag {
+			info := ctx.OtherModuleProvider(module, java.ClasspathFragmentProtoContentInfoProvider).(java.ClasspathFragmentProtoContentInfo)
+			if !info.ClasspathFragmentProtoGenerated {
+				ctx.OtherModuleErrorf(module, "is included in updatable apex %v, it must not set generate_classpaths_proto to false", ctx.ModuleName())
+			}
+		}
+	})
+}
+
+// checkJavaStableSdkVersion enforces that all Java deps are using stable SDKs to compile.
 func (a *apexBundle) checkJavaStableSdkVersion(ctx android.ModuleContext) {
 	// Visit direct deps only. As long as we guarantee top-level deps are using stable SDKs,
 	// java's checkLinkType guarantees correct usage for transitive deps
@@ -2383,7 +2405,7 @@
 	})
 }
 
-// Ensures that the all the dependencies are marked as available for this APEX
+// checkApexAvailability ensures that the all the dependencies are marked as available for this APEX.
 func (a *apexBundle) checkApexAvailability(ctx android.ModuleContext) {
 	// Let's be practical. Availability for test, host, and the VNDK apex isn't important
 	if ctx.Host() || a.testApex || a.vndkApex {
diff --git a/apex/apex_test.go b/apex/apex_test.go
index 03db524..6a7a562 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -6699,6 +6699,47 @@
 	`)
 }
 
+func TestUpdatable_should_not_set_generate_classpaths_proto(t *testing.T) {
+	testApexError(t, `"mysystemserverclasspathfragment" .* it must not set generate_classpaths_proto to false`, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			systemserverclasspath_fragments: [
+				"mysystemserverclasspathfragment",
+			],
+			min_sdk_version: "29",
+			updatable: true,
+		}
+
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+
+		java_library {
+			name: "foo",
+			srcs: ["b.java"],
+			min_sdk_version: "29",
+			installable: true,
+			apex_available: [
+				"myapex",
+			],
+		}
+
+		systemserverclasspath_fragment {
+			name: "mysystemserverclasspathfragment",
+			generate_classpaths_proto: false,
+			contents: [
+				"foo",
+			],
+			apex_available: [
+				"myapex",
+			],
+		}
+	`)
+}
+
 func TestNoUpdatableJarsInBootImage(t *testing.T) {
 	// Set the BootJars in dexpreopt.GlobalConfig and productVariables to the same value. This can
 	// result in an invalid configuration as it does not set the ArtApexJars and allows art apex
diff --git a/apex/systemserver_classpath_fragment_test.go b/apex/systemserver_classpath_fragment_test.go
index 95b6e23..537f51d 100644
--- a/apex/systemserver_classpath_fragment_test.go
+++ b/apex/systemserver_classpath_fragment_test.go
@@ -76,3 +76,54 @@
 		`mysystemserverclasspathfragment`,
 	})
 }
+
+func TestSystemserverclasspathFragmentNoGeneratedProto(t *testing.T) {
+	result := android.GroupFixturePreparers(
+		prepareForTestWithSystemserverclasspathFragment,
+		prepareForTestWithMyapex,
+	).RunTestWithBp(t, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			systemserverclasspath_fragments: [
+				"mysystemserverclasspathfragment",
+			],
+			updatable: false,
+		}
+
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+
+		java_library {
+			name: "foo",
+			srcs: ["b.java"],
+			installable: true,
+			apex_available: [
+				"myapex",
+			],
+		}
+
+		systemserverclasspath_fragment {
+			name: "mysystemserverclasspathfragment",
+			generate_classpaths_proto: false,
+			contents: [
+				"foo",
+			],
+			apex_available: [
+				"myapex",
+			],
+		}
+	`)
+
+	ensureExactContents(t, result.TestContext, "myapex", "android_common_myapex_image", []string{
+		"javalib/foo.jar",
+	})
+
+	java.CheckModuleDependencies(t, result.TestContext, "myapex", "android_common_myapex_image", []string{
+		`myapex.key`,
+		`mysystemserverclasspathfragment`,
+	})
+}
diff --git a/java/classpath_fragment.go b/java/classpath_fragment.go
index 4c1e749..3d72580 100644
--- a/java/classpath_fragment.go
+++ b/java/classpath_fragment.go
@@ -19,6 +19,7 @@
 import (
 	"fmt"
 	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
 	"strings"
 
 	"android/soong/android"
@@ -44,6 +45,11 @@
 }
 
 type classpathFragmentProperties struct {
+	// Whether to generated classpaths.proto config instance for the fragment. If the config is not
+	// generated, then relevant boot jars are added to platform classpath, i.e. platform_bootclasspath
+	// or platform_systemserverclasspath. This is useful for non-updatable APEX boot jars, to keep
+	// them as part of dexopt on device. Defaults to true.
+	Generate_classpaths_proto *bool
 }
 
 // classpathFragment interface is implemented by a module that contributes jars to a *CLASSPATH
@@ -101,24 +107,28 @@
 }
 
 func (c *ClasspathFragmentBase) generateClasspathProtoBuildActions(ctx android.ModuleContext, jars []classpathJar) {
-	outputFilename := strings.ToLower(c.classpathType.String()) + ".pb"
-	c.outputFilepath = android.PathForModuleOut(ctx, outputFilename).OutputPath
-	c.installDirPath = android.PathForModuleInstall(ctx, "etc", "classpaths")
+	generateProto := proptools.BoolDefault(c.properties.Generate_classpaths_proto, true)
+	if generateProto {
+		outputFilename := strings.ToLower(c.classpathType.String()) + ".pb"
+		c.outputFilepath = android.PathForModuleOut(ctx, outputFilename).OutputPath
+		c.installDirPath = android.PathForModuleInstall(ctx, "etc", "classpaths")
 
-	generatedJson := android.PathForModuleOut(ctx, outputFilename+".json")
-	writeClasspathsJson(ctx, generatedJson, jars)
+		generatedJson := android.PathForModuleOut(ctx, outputFilename+".json")
+		writeClasspathsJson(ctx, generatedJson, jars)
 
-	rule := android.NewRuleBuilder(pctx, ctx)
-	rule.Command().
-		BuiltTool("conv_classpaths_proto").
-		Flag("encode").
-		Flag("--format=json").
-		FlagWithInput("--input=", generatedJson).
-		FlagWithOutput("--output=", c.outputFilepath)
+		rule := android.NewRuleBuilder(pctx, ctx)
+		rule.Command().
+			BuiltTool("conv_classpaths_proto").
+			Flag("encode").
+			Flag("--format=json").
+			FlagWithInput("--input=", generatedJson).
+			FlagWithOutput("--output=", c.outputFilepath)
 
-	rule.Build("classpath_fragment", "Compiling "+c.outputFilepath.String())
+		rule.Build("classpath_fragment", "Compiling "+c.outputFilepath.String())
+	}
 
 	classpathProtoInfo := ClasspathFragmentProtoContentInfo{
+		ClasspathFragmentProtoGenerated:  generateProto,
 		ClasspathFragmentProtoInstallDir: c.installDirPath,
 		ClasspathFragmentProtoOutput:     c.outputFilepath,
 	}
@@ -164,6 +174,9 @@
 var ClasspathFragmentProtoContentInfoProvider = blueprint.NewProvider(ClasspathFragmentProtoContentInfo{})
 
 type ClasspathFragmentProtoContentInfo struct {
+	// Whether the classpaths.proto config is generated for the fragment.
+	ClasspathFragmentProtoGenerated bool
+
 	// ClasspathFragmentProtoOutput is an output path for the generated classpaths.proto config of this module.
 	//
 	// The file should be copied to a relevant place on device, see ClasspathFragmentProtoInstallDir