diff --git a/java/aar.go b/java/aar.go
index 6a883d3ad..6426ac365 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -520,6 +520,10 @@ func (a *AARImport) sdkVersion() string {
 	return proptools.StringDefault(a.properties.Sdk_version, defaultSdkVersion(a))
 }
 
+func (a *AARImport) systemModules() string {
+	return ""
+}
+
 func (a *AARImport) minSdkVersion() string {
 	if a.properties.Min_sdk_version != nil {
 		return *a.properties.Min_sdk_version
diff --git a/java/droiddoc.go b/java/droiddoc.go
index 2df2852a4..8a283cd59 100644
--- a/java/droiddoc.go
+++ b/java/droiddoc.go
@@ -67,9 +67,15 @@ type JavadocProperties struct {
 	// If set to false, don't allow this module(-docs.zip) to be exported. Defaults to true.
 	Installable *bool
 
-	// if not blank, set to the version of the sdk to compile against
+	// if not blank, set to the version of the sdk to compile against.
+	// Defaults to compiling against the current platform.
 	Sdk_version *string `android:"arch_variant"`
 
+	// When targeting 1.9 and above, override the modules to use with --system,
+	// otherwise provides defaults libraries to add to the bootclasspath.
+	// Defaults to "none"
+	System_modules *string
+
 	Aidl struct {
 		// Top level directories to pass to aidl tool
 		Include_dirs []string
@@ -401,6 +407,10 @@ func (j *Javadoc) sdkVersion() string {
 	return proptools.StringDefault(j.properties.Sdk_version, defaultSdkVersion(j))
 }
 
+func (j *Javadoc) systemModules() string {
+	return proptools.String(j.properties.System_modules)
+}
+
 func (j *Javadoc) minSdkVersion() string {
 	return j.sdkVersion()
 }
@@ -427,6 +437,10 @@ func (j *Javadoc) addDeps(ctx android.BottomUpMutatorContext) {
 				}
 				ctx.AddVariationDependencies(nil, bootClasspathTag, sdkDep.modules...)
 			}
+		} else if sdkDep.systemModules != "" {
+			// Add the system modules to both the system modules and bootclasspath.
+			ctx.AddVariationDependencies(nil, systemModulesTag, sdkDep.systemModules)
+			ctx.AddVariationDependencies(nil, bootClasspathTag, sdkDep.systemModules)
 		}
 	}
 
@@ -514,6 +528,10 @@ func (j *Javadoc) collectDeps(ctx android.ModuleContext) deps {
 		case bootClasspathTag:
 			if dep, ok := module.(Dependency); ok {
 				deps.bootClasspath = append(deps.bootClasspath, dep.ImplementationJars()...)
+			} else if sm, ok := module.(*SystemModules); ok {
+				// A system modules dependency has been added to the bootclasspath
+				// so add its libs to the bootclasspath.
+				deps.bootClasspath = append(deps.bootClasspath, sm.headerJars...)
 			} else {
 				panic(fmt.Errorf("unknown dependency %q for %q", otherName, ctx.ModuleName()))
 			}
diff --git a/java/java.go b/java/java.go
index 4264ba908..8c511eeee 100644
--- a/java/java.go
+++ b/java/java.go
@@ -270,7 +270,8 @@ type CompilerDeviceProperties struct {
 		Proguard_flags_files []string `android:"path"`
 	}
 
-	// When targeting 1.9, override the modules to use with --system
+	// When targeting 1.9 and above, override the modules to use with --system,
+	// otherwise provides defaults libraries to add to the bootclasspath.
 	System_modules *string
 
 	UncompressDex bool `blueprint:"mutated"`
@@ -457,7 +458,10 @@ type checkVendorModuleContext interface {
 type sdkDep struct {
 	useModule, useFiles, useDefaultLibs, invalidVersion bool
 
-	modules       []string
+	modules []string
+
+	// The default system modules to use. Will be an empty string if no system
+	// modules are to be used.
 	systemModules string
 
 	frameworkResModule string
@@ -496,6 +500,10 @@ func (j *Module) sdkVersion() string {
 	return proptools.StringDefault(j.deviceProperties.Sdk_version, defaultSdkVersion(j))
 }
 
+func (j *Module) systemModules() string {
+	return proptools.String(j.deviceProperties.System_modules)
+}
+
 func (j *Module) minSdkVersion() string {
 	if j.deviceProperties.Min_sdk_version != nil {
 		return *j.deviceProperties.Min_sdk_version
@@ -528,13 +536,10 @@ func (j *Module) deps(ctx android.BottomUpMutatorContext) {
 					ctx.AddVariationDependencies(nil, proguardRaiseTag, config.DefaultLibraries...)
 				}
 			}
-		} else if j.deviceProperties.System_modules == nil {
-			ctx.PropertyErrorf("sdk_version",
-				`system_modules is required to be set when sdk_version is "none", did you mean "core_platform"`)
-		} else if *j.deviceProperties.System_modules != "none" {
+		} else if sdkDep.systemModules != "" {
 			// Add the system modules to both the system modules and bootclasspath.
-			ctx.AddVariationDependencies(nil, systemModulesTag, *j.deviceProperties.System_modules)
-			ctx.AddVariationDependencies(nil, bootClasspathTag, *j.deviceProperties.System_modules)
+			ctx.AddVariationDependencies(nil, systemModulesTag, sdkDep.systemModules)
+			ctx.AddVariationDependencies(nil, bootClasspathTag, sdkDep.systemModules)
 		}
 		if ctx.ModuleName() == "android_stubs_current" ||
 			ctx.ModuleName() == "android_system_stubs_current" ||
diff --git a/java/sdk.go b/java/sdk.go
index 3451774c0..c6a9a73c8 100644
--- a/java/sdk.go
+++ b/java/sdk.go
@@ -39,6 +39,8 @@ var apiFingerprintPathKey = android.NewOnceKey("apiFingerprintPathKey")
 type sdkContext interface {
 	// sdkVersion returns the sdk_version property of the current module, or an empty string if it is not set.
 	sdkVersion() string
+	// systemModules returns the system_modules property of the current module, or an empty string if it is not set.
+	systemModules() string
 	// minSdkVersion returns the min_sdk_version property of the current module, or sdkVersion() if it is not set.
 	minSdkVersion() string
 	// targetSdkVersion returns the target_sdk_version property of the current module, or sdkVersion() if it is not set.
@@ -185,8 +187,18 @@ func decodeSdkDep(ctx android.BaseModuleContext, sdkContext sdkContext) sdkDep {
 			frameworkResModule: "framework-res",
 		}
 	case "none":
+		systemModules := sdkContext.systemModules()
+		if systemModules == "" {
+			ctx.PropertyErrorf("sdk_version",
+				`system_modules is required to be set to a non-empty value when sdk_version is "none", did you mean sdk_version: "core_platform"?`)
+		} else if systemModules == "none" {
+			// Normalize no system modules to an empty string.
+			systemModules = ""
+		}
+
 		return sdkDep{
 			noStandardLibs: true,
+			systemModules:  systemModules,
 		}
 	case "core_platform":
 		return sdkDep{