improved and added to test cases for @Builder.

Eclipse's implementation continues to pass them all.

test/transform/resource/after-ecj/BuilderWithExistingBuilderClass.java

@@ -0,0 +1,33 @@
+import lombok.experimental.Builder;
+class BuilderWithExistingBuilderClass<T, K extends Number> {
+  public static class BuilderWithExistingBuilderClassBuilder<Z extends Number> {
+    private boolean arg2;
+    private String arg3;
+    private Z arg1;
+    public void arg2(boolean arg) {
+    }
+    @java.lang.SuppressWarnings("all") BuilderWithExistingBuilderClassBuilder() {
+      super();
+    }
+    public @java.lang.SuppressWarnings("all") BuilderWithExistingBuilderClassBuilder<Z> arg1(final Z arg1) {
+      this.arg1 = arg1;
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderWithExistingBuilderClassBuilder<Z> arg3(final String arg3) {
+      this.arg3 = arg3;
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderWithExistingBuilderClass<String, Z> build() {
+      return BuilderWithExistingBuilderClass.<Z>staticMethod(arg1, arg2, arg3);
+    }
+  }
+  BuilderWithExistingBuilderClass() {
+    super();
+  }
+  public static @Builder <Z extends Number>BuilderWithExistingBuilderClass<String, Z> staticMethod(Z arg1, boolean arg2, String arg3) {
+    return null;
+  }
+  public static @java.lang.SuppressWarnings("all") <Z extends Number>BuilderWithExistingBuilderClassBuilder<Z> builder() {
+    return new BuilderWithExistingBuilderClassBuilder<Z>();
+  }
+}