diff --git a/java/androidmk.go b/java/androidmk.go
index 90fdd0f..ad0e171 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -55,6 +55,11 @@
 }
 
 func (library *Library) AndroidMk() android.AndroidMkData {
+	if !library.IsForPlatform() {
+		return android.AndroidMkData{
+			Disabled: true,
+		}
+	}
 	return android.AndroidMkData{
 		Class:      "JAVA_LIBRARIES",
 		OutputFile: android.OptionalPathForPath(library.outputFile),
@@ -141,6 +146,11 @@
 }
 
 func (prebuilt *Import) AndroidMk() android.AndroidMkData {
+	if !prebuilt.IsForPlatform() {
+		return android.AndroidMkData{
+			Disabled: true,
+		}
+	}
 	return android.AndroidMkData{
 		Class:      "JAVA_LIBRARIES",
 		OutputFile: android.OptionalPathForPath(prebuilt.combinedClasspathFile),
@@ -157,6 +167,11 @@
 }
 
 func (prebuilt *DexImport) AndroidMk() android.AndroidMkData {
+	if !prebuilt.IsForPlatform() {
+		return android.AndroidMkData{
+			Disabled: true,
+		}
+	}
 	return android.AndroidMkData{
 		Class:      "JAVA_LIBRARIES",
 		OutputFile: android.OptionalPathForPath(prebuilt.maybeStrippedDexJarFile),
diff --git a/java/hiddenapi_singleton.go b/java/hiddenapi_singleton.go
index c83dda1..8379f53 100644
--- a/java/hiddenapi_singleton.go
+++ b/java/hiddenapi_singleton.go
@@ -152,6 +152,14 @@
 		// Collect dex jar paths for modules that had hiddenapi encode called on them.
 		if h, ok := module.(hiddenAPIIntf); ok {
 			if jar := h.bootDexJar(); jar != nil {
+				// For a java lib included in an APEX, only take the one built for
+				// the platform variant, and skip the variants for APEXes.
+				// Otherwise, the hiddenapi tool will complain about duplicated classes
+				if a, ok := module.(android.ApexModule); ok {
+					if android.InAnyApex(module.Name()) && !a.IsForPlatform() {
+						return
+					}
+				}
 				bootDexJars = append(bootDexJars, jar)
 			}
 		}
diff --git a/java/java.go b/java/java.go
index f3e10be..5f4a090 100644
--- a/java/java.go
+++ b/java/java.go
@@ -267,6 +267,7 @@
 type Module struct {
 	android.ModuleBase
 	android.DefaultableModuleBase
+	android.ApexModuleBase
 
 	properties       CompilerProperties
 	protoProperties  android.ProtoProperties
@@ -1550,7 +1551,8 @@
 	j.deviceProperties.UncompressDex = j.dexpreopter.uncompressedDex
 	j.compile(ctx, nil)
 
-	if (Bool(j.properties.Installable) || ctx.Host()) && !android.DirectlyInAnyApex(ctx, ctx.ModuleName()) {
+	exclusivelyForApex := android.InAnyApex(ctx.ModuleName()) && !j.IsForPlatform()
+	if (Bool(j.properties.Installable) || ctx.Host()) && !exclusivelyForApex {
 		j.installFile = ctx.InstallFile(android.PathForModuleInstall(ctx, "framework"),
 			ctx.ModuleName()+".jar", j.outputFile)
 	}
@@ -1581,6 +1583,7 @@
 		&module.Module.protoProperties)
 
 	InitJavaModule(module, android.HostAndDeviceSupported)
+	android.InitApexModule(module)
 	return module
 }
 
@@ -1603,6 +1606,7 @@
 	module.Module.properties.Installable = proptools.BoolPtr(true)
 
 	InitJavaModule(module, android.HostSupported)
+	android.InitApexModule(module)
 	return module
 }
 
@@ -1858,6 +1862,7 @@
 type Import struct {
 	android.ModuleBase
 	android.DefaultableModuleBase
+	android.ApexModuleBase
 	prebuilt android.Prebuilt
 
 	properties ImportProperties
@@ -2014,6 +2019,7 @@
 
 	android.InitPrebuiltModule(module, &module.properties.Jars)
 	InitJavaModule(module, android.HostAndDeviceSupported)
+	android.InitApexModule(module)
 	return module
 }
 
@@ -2029,6 +2035,7 @@
 
 	android.InitPrebuiltModule(module, &module.properties.Jars)
 	InitJavaModule(module, android.HostSupported)
+	android.InitApexModule(module)
 	return module
 }
 
@@ -2041,6 +2048,7 @@
 type DexImport struct {
 	android.ModuleBase
 	android.DefaultableModuleBase
+	android.ApexModuleBase
 	prebuilt android.Prebuilt
 
 	properties DexImportProperties
@@ -2132,6 +2140,7 @@
 
 	android.InitPrebuiltModule(module, &module.properties.Jars)
 	InitJavaModule(module, android.DeviceSupported)
+	android.InitApexModule(module)
 	return module
 }
 
@@ -2141,6 +2150,7 @@
 type Defaults struct {
 	android.ModuleBase
 	android.DefaultsModuleBase
+	android.ApexModuleBase
 }
 
 // java_defaults provides a set of properties that can be inherited by other java or android modules.
@@ -2199,7 +2209,7 @@
 	)
 
 	android.InitDefaultsModule(module)
-
+	android.InitApexModule(module)
 	return module
 }