diff --git a/java/builder.go b/java/builder.go
index 8992f68..304cd27 100644
--- a/java/builder.go
+++ b/java/builder.go
@@ -135,23 +135,24 @@
 	protoOutFlag string
 }
 
-func TransformJavaToClasses(ctx android.ModuleContext, srcFiles, srcFileLists android.Paths,
-	flags javaBuilderFlags, deps android.Paths) android.ModuleOutPath {
+func TransformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
+	srcFiles, srcFileLists android.Paths,
+	flags javaBuilderFlags, deps android.Paths) {
 
-	return transformJavaToClasses(ctx, srcFiles, srcFileLists, flags, deps,
-		"classes-compiled.jar", "", "javac", javac)
+	transformJavaToClasses(ctx, outputFile, srcFiles, srcFileLists, flags, deps,
+		"", "javac", javac)
 }
 
-func RunErrorProne(ctx android.ModuleContext, srcFiles, srcFileLists android.Paths,
-	flags javaBuilderFlags) android.Path {
+func RunErrorProne(ctx android.ModuleContext, outputFile android.WritablePath,
+	srcFiles, srcFileLists android.Paths,
+	flags javaBuilderFlags) {
 
 	if config.ErrorProneJar == "" {
 		ctx.ModuleErrorf("cannot build with Error Prone, missing external/error_prone?")
-		return nil
 	}
 
-	return transformJavaToClasses(ctx, srcFiles, srcFileLists, flags, nil,
-		"classes-errorprone.list", "-errorprone", "errorprone", errorprone)
+	transformJavaToClasses(ctx, outputFile, srcFiles, srcFileLists, flags, nil,
+		"-errorprone", "errorprone", errorprone)
 }
 
 // transformJavaToClasses takes source files and converts them to a jar containing .class files.
@@ -166,11 +167,10 @@
 // be printed at build time.  The stem argument provides the file name of the output jar, and
 // suffix will be appended to various intermediate files and directories to avoid collisions when
 // this function is called twice in the same module directory.
-func transformJavaToClasses(ctx android.ModuleContext, srcFiles, srcFileLists android.Paths,
-	flags javaBuilderFlags, deps android.Paths, stem, suffix, desc string,
-	rule blueprint.Rule) android.ModuleOutPath {
-
-	outputFile := android.PathForModuleOut(ctx, stem)
+func transformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
+	srcFiles, srcFileLists android.Paths,
+	flags javaBuilderFlags, deps android.Paths,
+	intermediatesSuffix, desc string, rule blueprint.Rule) {
 
 	javacFlags := flags.javacFlags
 	if len(srcFileLists) > 0 {
@@ -200,19 +200,15 @@
 			"javacFlags":    javacFlags,
 			"bootClasspath": bootClasspath,
 			"classpath":     flags.classpath.JavaClasspath(),
-			"outDir":        android.PathForModuleOut(ctx, "classes"+suffix).String(),
-			"annoDir":       android.PathForModuleOut(ctx, "anno"+suffix).String(),
+			"outDir":        android.PathForModuleOut(ctx, "classes"+intermediatesSuffix).String(),
+			"annoDir":       android.PathForModuleOut(ctx, "anno"+intermediatesSuffix).String(),
 			"javaVersion":   flags.javaVersion,
 		},
 	})
-
-	return outputFile
 }
 
-func TransformResourcesToJar(ctx android.ModuleContext, jarArgs []string,
-	deps android.Paths) android.Path {
-
-	outputFile := android.PathForModuleOut(ctx, "res.jar")
+func TransformResourcesToJar(ctx android.ModuleContext, outputFile android.WritablePath,
+	jarArgs []string, deps android.Paths) {
 
 	ctx.ModuleBuild(pctx, android.ModuleBuildParams{
 		Rule:        jar,
@@ -223,18 +219,10 @@
 			"jarArgs": strings.Join(jarArgs, " "),
 		},
 	})
-
-	return outputFile
 }
 
-func TransformJarsToJar(ctx android.ModuleContext, stem string, jars android.Paths,
-	manifest android.OptionalPath, stripDirs bool) android.Path {
-
-	outputFile := android.PathForModuleOut(ctx, stem)
-
-	if len(jars) == 1 && !manifest.Valid() {
-		return jars[0]
-	}
+func TransformJarsToJar(ctx android.ModuleContext, outputFile android.WritablePath,
+	jars android.Paths, manifest android.OptionalPath, stripDirs bool) {
 
 	var deps android.Paths
 
@@ -258,14 +246,11 @@
 			"jarArgs": strings.Join(jarArgs, " "),
 		},
 	})
-
-	return outputFile
 }
 
-func TransformDesugar(ctx android.ModuleContext, classesJar android.Path,
-	flags javaBuilderFlags) android.Path {
+func TransformDesugar(ctx android.ModuleContext, outputFile android.WritablePath,
+	classesJar android.Path, flags javaBuilderFlags) {
 
-	outputFile := android.PathForModuleOut(ctx, "classes-desugar.jar")
 	dumpDir := android.PathForModuleOut(ctx, "desugar_dumped_classes")
 
 	javaFlags := ""
@@ -294,17 +279,14 @@
 			"desugarFlags":   flags.desugarFlags,
 		},
 	})
-
-	return outputFile
 }
 
 // Converts a classes.jar file to classes*.dex, then combines the dex files with any resources
 // in the classes.jar file into a dex jar.
-func TransformClassesJarToDexJar(ctx android.ModuleContext, stem string, classesJar android.Path,
-	flags javaBuilderFlags) android.Path {
+func TransformClassesJarToDexJar(ctx android.ModuleContext, outputFile android.WritablePath,
+	classesJar android.Path, flags javaBuilderFlags) {
 
 	outDir := android.PathForModuleOut(ctx, "dex")
-	outputFile := android.PathForModuleOut(ctx, stem)
 
 	ctx.ModuleBuild(pctx, android.ModuleBuildParams{
 		Rule:        dx,
@@ -316,12 +298,10 @@
 			"outDir":  outDir.String(),
 		},
 	})
-
-	return outputFile
 }
 
-func TransformJarJar(ctx android.ModuleContext, classesJar android.Path, rulesFile android.Path) android.ModuleOutPath {
-	outputFile := android.PathForModuleOut(ctx, "classes-jarjar.jar")
+func TransformJarJar(ctx android.ModuleContext, outputFile android.WritablePath,
+	classesJar android.Path, rulesFile android.Path) {
 	ctx.ModuleBuild(pctx, android.ModuleBuildParams{
 		Rule:        jarjar,
 		Description: "jarjar",
@@ -332,8 +312,6 @@
 			"rulesFile": rulesFile.String(),
 		},
 	})
-
-	return outputFile
 }
 
 type classpath []android.Path
diff --git a/java/java.go b/java/java.go
index c3b7557..6485f06 100644
--- a/java/java.go
+++ b/java/java.go
@@ -501,12 +501,14 @@
 			// a rebuild when error-prone is turned off).
 			// TODO(ccross): Once we always compile with javac9 we may be able to conditionally
 			//    enable error-prone without affecting the output class files.
-			errorprone := RunErrorProne(ctx, srcFiles, srcFileLists, flags)
+			errorprone := android.PathForModuleOut(ctx, "classes-errorprone.list")
+			RunErrorProne(ctx, errorprone, srcFiles, srcFileLists, flags)
 			extraJarDeps = append(extraJarDeps, errorprone)
 		}
 
 		// Compile java sources into .class files
-		classes := TransformJavaToClasses(ctx, srcFiles, srcFileLists, flags, extraJarDeps)
+		classes := android.PathForModuleOut(ctx, "classes-compiled.jar")
+		TransformJavaToClasses(ctx, classes, srcFiles, srcFileLists, flags, extraJarDeps)
 		if ctx.Failed() {
 			return
 		}
@@ -533,7 +535,8 @@
 	}
 
 	if len(resArgs) > 0 {
-		resourceJar := TransformResourcesToJar(ctx, resArgs, resDeps)
+		resourceJar := android.PathForModuleOut(ctx, "res.jar")
+		TransformResourcesToJar(ctx, resourceJar, resArgs, resDeps)
 		if ctx.Failed() {
 			return
 		}
@@ -548,12 +551,23 @@
 
 	// Combine the classes built from sources, any manifests, and any static libraries into
 	// classes.jar.  If there is only one input jar this step will be skipped.
-	outputFile := TransformJarsToJar(ctx, "classes.jar", jars, manifest, false)
+	var outputFile android.Path
+
+	if len(jars) == 1 && !manifest.Valid() {
+		// Optimization: skip the combine step if there is nothing to do
+		outputFile = jars[0]
+	} else {
+		combinedJar := android.PathForModuleOut(ctx, "classes.jar")
+		TransformJarsToJar(ctx, combinedJar, jars, manifest, false)
+		outputFile = combinedJar
+	}
 
 	if j.properties.Jarjar_rules != nil {
 		jarjar_rules := android.PathForModuleSrc(ctx, *j.properties.Jarjar_rules)
 		// Transform classes.jar into classes-jarjar.jar
-		outputFile = TransformJarJar(ctx, outputFile, jarjar_rules)
+		jarjarFile := android.PathForModuleOut(ctx, "classes-jarjar.jar")
+		TransformJarJar(ctx, jarjarFile, outputFile, jarjar_rules)
+		outputFile = jarjarFile
 		if ctx.Failed() {
 			return
 		}
@@ -609,13 +623,17 @@
 
 		flags.desugarFlags = strings.Join(desugarFlags, " ")
 
-		desugarJar := TransformDesugar(ctx, outputFile, flags)
+		desugarJar := android.PathForModuleOut(ctx, "classes-desugar.jar")
+		TransformDesugar(ctx, desugarJar, outputFile, flags)
+		outputFile = desugarJar
 		if ctx.Failed() {
 			return
 		}
 
 		// Compile classes.jar into classes.dex and then javalib.jar
-		outputFile = TransformClassesJarToDexJar(ctx, "javalib.jar", desugarJar, flags)
+		javalibJar := android.PathForModuleOut(ctx, "javalib.jar")
+		TransformClassesJarToDexJar(ctx, javalibJar, desugarJar, flags)
+		outputFile = javalibJar
 		if ctx.Failed() {
 			return
 		}
@@ -790,7 +808,9 @@
 func (j *Import) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	j.classpathFiles = android.PathsForModuleSrc(ctx, j.properties.Jars)
 
-	j.combinedClasspathFile = TransformJarsToJar(ctx, "classes.jar", j.classpathFiles, android.OptionalPath{}, false)
+	outputFile := android.PathForModuleOut(ctx, "classes.jar")
+	TransformJarsToJar(ctx, outputFile, j.classpathFiles, android.OptionalPath{}, false)
+	j.combinedClasspathFile = outputFile
 }
 
 var _ Dependency = (*Import)(nil)