diff --git a/compiler/src/main/cpp/capnpc-java.c++ b/compiler/src/main/cpp/capnpc-java.c++
index ffeeeac..c5d3f2a 100644
--- a/compiler/src/main/cpp/capnpc-java.c++
+++ b/compiler/src/main/cpp/capnpc-java.c++
@@ -179,11 +179,10 @@ public:
   CapnpcJavaMain(kj::ProcessContext& context): context(context) {}
 
   kj::MainFunc getMain() {
-    return kj::MainBuilder(context, "Cap'n Proto loopback plugin version " VERSION,
-          "This is a Cap'n Proto compiler plugin which \"de-compiles\" the schema back into "
-          "Cap'n Proto schema language format, with comments showing the offsets chosen by the "
-          "compiler.  This is meant to be run using the Cap'n Proto compiler, e.g.:\n"
-          "    capnp compile -ocapnp foo.capnp")
+    return kj::MainBuilder(context, "Cap'n Proto Java plugin version " VERSION,
+          "This is a Cap'n Proto compiler plugin which generates Java code."
+          " This is meant to be run using the Cap'n Proto compiler, e.g.:\n"
+          "    capnp compile -ojava foo.capnp")
         .callAfterParsing(KJ_BIND_METHOD(*this, run))
         .build();
   }
@@ -1006,6 +1005,11 @@ private:
           case schema::Type::UINT64:
           case schema::Type::FLOAT32:
           case schema::Type::FLOAT64:
+            builderFactoryType = kj::str("ord.capnproto.PrimitiveElementFactory.",
+                                         toUpperCase(kj::str(typeName(typeBody.getList().getElementType()))));
+            readerFactoryType = kj::str(builderFactoryType);
+            primitiveElement = true;
+            break;
           case schema::Type::ENUM:
             primitiveElement = true;
             break;
diff --git a/runtime/src/main/java/org/capnproto/PrimitiveElementFactory.java b/runtime/src/main/java/org/capnproto/PrimitiveElementFactory.java
index 6a906ba..25bd2c2 100644
--- a/runtime/src/main/java/org/capnproto/PrimitiveElementFactory.java
+++ b/runtime/src/main/java/org/capnproto/PrimitiveElementFactory.java
@@ -4,6 +4,7 @@ public interface PrimitiveElementFactory<T> {
     public T get(ListReader listReader, int index);
 
     public static final PrimitiveElementFactory<Void> VOID = new PrimitiveElementFactoryVoid();
+//    public static final PrimitiveElementFactory<boolean> BOOLEAN = new PrimitiveElementFactoryBoolean();
 }
 
 
@@ -13,3 +14,11 @@ class PrimitiveElementFactoryVoid implements PrimitiveElementFactory<Void> {
     }
 }
 
+/*
+argh, generics must be boxed.
+class PrimitiveElementFactoryBoolean implements PrimitiveElementFactory<boolean> {
+    public boolean get(ListReader listReader, int index) {
+        throw new Error("unimplemented");
+    }
+}
+*/