diff --git a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/EnumGenerator.java b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/EnumGenerator.java
index aeca39279..0347e15a0 100644
--- a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/EnumGenerator.java
+++ b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/EnumGenerator.java
@@ -37,7 +37,7 @@ public final class EnumGenerator<T extends ShapeDirective<Shape, CodeGenerationC
 
     @Override
     public void accept(T directive) {
-        if (directive.symbol().getProperty(SymbolProperties.EXTERNAL_TYPE).isPresent()) {
+        if (directive.symbol().getProperty(SymbolProperties.EXTERNAL_TYPE).orElse(false)) {
             // skip external types
             return;
         }
diff --git a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureGenerator.java b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureGenerator.java
index 20efd40e4..42c2f8d6f 100644
--- a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureGenerator.java
+++ b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/StructureGenerator.java
@@ -90,7 +90,7 @@ public final class StructureGenerator<
     public void accept(T directive) {
         if (directive.shape().hasTrait(UnitTypeTrait.class) || directive.symbol()
                 .getProperty(SymbolProperties.EXTERNAL_TYPE)
-                .isPresent()) {
+                .orElse(false)) {
             // Skip Unit structures or external types.
             return;
         }
diff --git a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/UnionGenerator.java b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/UnionGenerator.java
index 80a2760fc..57120667f 100644
--- a/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/UnionGenerator.java
+++ b/codegen/codegen-core/src/main/java/software/amazon/smithy/java/codegen/generators/UnionGenerator.java
@@ -37,7 +37,7 @@ public final class UnionGenerator
 
     @Override
     public void accept(GenerateUnionDirective<CodeGenerationContext, JavaCodegenSettings> directive) {
-        if (directive.symbol().getProperty(SymbolProperties.EXTERNAL_TYPE).isPresent()) {
+        if (directive.symbol().getProperty(SymbolProperties.EXTERNAL_TYPE).orElse(false)) {
             // Skip external types.
             return;
         }