Do not propagate <uses-library> deps through static SDK component libs.

If some Java library/app depends on an SDK component library (e.g. stubs
library), then it transitively depends on the SDK library itself
(because the component library has a dependency on its SDK library).

Previously having this transitive dependency resulted in adding the SDK
library to the <uses-library> dependencies of the library/app. However,
this doesn't make sense if the app has a *static* dependency on the
component library. This patch stops adding <uses-library> dependency in
that case.

Bug: 132357300
Test: m nothing
Test: added new Soong test that would previously fail with an error:
   invalid build path for <uses-library> "fred"
Change-Id: I697a65e461037c95ec56b6c321afa4ec52ccbbec

java/aar.go

@@ -407,6 +407,7 @@ func aaptLibs(ctx android.ModuleContext, sdkContext sdkContext, classLoaderConte
 
 	ctx.VisitDirectDeps(func(module android.Module) {
 		depName := ctx.OtherModuleName(module)
+		depTag := ctx.OtherModuleDependencyTag(module)
 
 		var exportPackage android.Path
 		aarDep, _ := module.(AndroidLibraryDependency)
@@ -414,7 +415,7 @@ func aaptLibs(ctx android.ModuleContext, sdkContext sdkContext, classLoaderConte
 			exportPackage = aarDep.ExportPackage()
 		}
 
-		switch ctx.OtherModuleDependencyTag(module) {
+		switch depTag {
 		case instrumentationForTag:
 			// Nothing, instrumentationForTag is treated as libTag for javac but not for aapt2.
 		case libTag:
@@ -439,7 +440,6 @@ func aaptLibs(ctx android.ModuleContext, sdkContext sdkContext, classLoaderConte
 				transitiveStaticLibs = append(transitiveStaticLibs, aarDep.ExportedStaticPackages()...)
 				transitiveStaticLibs = append(transitiveStaticLibs, exportPackage)
 				transitiveStaticLibManifests = append(transitiveStaticLibManifests, aarDep.ExportedManifests()...)
-				classLoaderContexts.AddContextMap(aarDep.ClassLoaderContexts(), depName)
 				if aarDep.ExportedAssets().Valid() {
 					assets = append(assets, aarDep.ExportedAssets().Path())
 				}
@@ -458,11 +458,8 @@ func aaptLibs(ctx android.ModuleContext, sdkContext sdkContext, classLoaderConte
 			}
 		}
 
-		// Add nested dependencies after processing the direct dependency: if it is a <uses-library>,
-		// nested context is added as its subcontext, and should not be re-added at the top-level.
-		if dep, ok := module.(Dependency); ok {
-			classLoaderContexts.AddContextMap(dep.ClassLoaderContexts(), depName)
-		}
+		// Merge dep's CLC after processing the dep itself (which may add its own <uses-library>).
+		maybeAddCLCFromDep(module, depTag, depName, classLoaderContexts)
 	})
 
 	deps = append(deps, sharedLibs...)

java/app_test.go

@@ -2729,6 +2729,13 @@ func TestUsesLibraries(t *testing.T) {
 			sdk_version: "current",
 		}
 
+		java_sdk_library {
+			name: "fred",
+			srcs: ["a.java"],
+			api_packages: ["fred"],
+			sdk_version: "current",
+		}
+
 		java_sdk_library {
 			name: "bar",
 			srcs: ["a.java"],
@@ -2753,7 +2760,12 @@ func TestUsesLibraries(t *testing.T) {
 			name: "app",
 			srcs: ["a.java"],
 			libs: ["qux", "quuz.stubs"],
-			static_libs: ["static-runtime-helper"],
+			static_libs: [
+				"static-runtime-helper",
+				// statically linked component libraries should not pull their SDK libraries,
+				// so "fred" should not be added to class loader context
+				"fred.stubs",
+			],
 			uses_libs: ["foo"],
 			sdk_version: "current",
 			optional_uses_libs: [

java/java.go

@@ -1050,7 +1050,6 @@ func (j *Module) collectDeps(ctx android.ModuleContext) deps {
 			switch tag {
 			case libTag:
 				deps.classpath = append(deps.classpath, dep.SdkHeaderJars(ctx, j.sdkVersion())...)
-				// names of sdk libs that are directly depended are exported
 				j.classLoaderContexts.MaybeAddContext(ctx, dep.OptionalImplicitSdkLibrary(),
 					dep.DexJarBuildPath(), dep.DexJarInstallPath())
 			case staticLibTag:
@@ -1062,7 +1061,6 @@ func (j *Module) collectDeps(ctx android.ModuleContext) deps {
 				deps.bootClasspath = append(deps.bootClasspath, dep.HeaderJars()...)
 			case libTag, instrumentationForTag:
 				deps.classpath = append(deps.classpath, dep.HeaderJars()...)
-				// sdk lib names from dependencies are re-exported
 				j.classLoaderContexts.AddContextMap(dep.ClassLoaderContexts(), otherName)
 				deps.aidlIncludeDirs = append(deps.aidlIncludeDirs, dep.AidlIncludeDirs()...)
 				pluginJars, pluginClasses, disableTurbine := dep.ExportedPlugins()
@@ -1075,8 +1073,6 @@ func (j *Module) collectDeps(ctx android.ModuleContext) deps {
 				deps.staticJars = append(deps.staticJars, dep.ImplementationJars()...)
 				deps.staticHeaderJars = append(deps.staticHeaderJars, dep.HeaderJars()...)
 				deps.staticResourceJars = append(deps.staticResourceJars, dep.ResourceJars()...)
-				// sdk lib names from dependencies are re-exported
-				j.classLoaderContexts.AddContextMap(dep.ClassLoaderContexts(), otherName)
 				deps.aidlIncludeDirs = append(deps.aidlIncludeDirs, dep.AidlIncludeDirs()...)
 				pluginJars, pluginClasses, disableTurbine := dep.ExportedPlugins()
 				addPlugins(&deps, pluginJars, pluginClasses...)
@@ -1151,6 +1147,9 @@ func (j *Module) collectDeps(ctx android.ModuleContext) deps {
 				deps.systemModules = &systemModules{outputDir, outputDeps}
 			}
 		}
+
+		// Merge dep's CLC after processing the dep itself (which may add its own <uses-library>).
+		maybeAddCLCFromDep(module, tag, otherName, j.classLoaderContexts)
 	})
 
 	return deps
@@ -2781,8 +2780,6 @@ func (j *Import) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			switch tag {
 			case libTag, staticLibTag:
 				flags.classpath = append(flags.classpath, dep.HeaderJars()...)
-				// sdk lib names from dependencies are re-exported
-				j.classLoaderContexts.AddContextMap(dep.ClassLoaderContexts(), otherName)
 			case bootClasspathTag:
 				flags.bootClasspath = append(flags.bootClasspath, dep.HeaderJars()...)
 			}
@@ -2790,10 +2787,12 @@ func (j *Import) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			switch tag {
 			case libTag:
 				flags.classpath = append(flags.classpath, dep.SdkHeaderJars(ctx, j.sdkVersion())...)
-				// names of sdk libs that are directly depended are exported
 				j.classLoaderContexts.AddContext(ctx, otherName, dep.DexJarBuildPath(), dep.DexJarInstallPath())
 			}
 		}
+
+		// Merge dep's CLC after processing the dep itself (which may add its own <uses-library>).
+		maybeAddCLCFromDep(module, tag, otherName, j.classLoaderContexts)
 	})
 
 	var installFile android.Path
@@ -3214,3 +3213,31 @@ var Bool = proptools.Bool
 var BoolDefault = proptools.BoolDefault
 var String = proptools.String
 var inList = android.InList
+
+// Add class loader context of a given dependency to the given class loader context, provided that
+// all the necessary conditions are met.
+func maybeAddCLCFromDep(depModule android.Module, depTag blueprint.DependencyTag,
+	depName string, clcMap dexpreopt.ClassLoaderContextMap) {
+
+	if dep, ok := depModule.(Dependency); ok {
+		if depTag == libTag {
+			// Ok, propagate <uses-library> through non-static library dependencies.
+		} else if depTag == staticLibTag {
+			// Propagate <uses-library> through static library dependencies, unless it is a
+			// component library (such as stubs). Component libraries have a dependency on their
+			// SDK library, which should not be pulled just because of a static component library.
+			if comp, isComp := depModule.(SdkLibraryComponentDependency); isComp {
+				if compName := comp.OptionalImplicitSdkLibrary(); compName != nil {
+					dep = nil
+				}
+			}
+		} else {
+			// Don't propagate <uses-library> for other dependency tags.
+			dep = nil
+		}
+
+		if dep != nil {
+			clcMap.AddContextMap(dep.ClassLoaderContexts(), depName)
+		}
+	}
+}