fix issue kongchen#17

src/main/java/com/github/kongchen/swagger/docgen/mustache/OutputTemplate.java

@@ -45,6 +45,9 @@ public Set<MustacheDataType> getDataTypes() {
     }
 
     public void addDateType(MustacheDocument mustacheDocument, MustacheDataType dataType) {
+        if (dataTypes.contains(dataType)) {
+            return;
+        }
         dataTypes.add(dataType);
         for (MustacheItem item : dataType.getItems()) {
             String trueType = TypeUtils.getTrueType(item.getType());

src/test/java/com/github/kongchen/swagger/docgen/mavenplugin/MavenDocumentSourceTest.java

@@ -40,6 +40,16 @@ private void prepare() {
         apiSource.setSwaggerDirectory(null);
     }
 
+    @Test
+    public void testIssue17() throws Exception, GenerateException {
+        apiSource.setLocations("issue17");
+        AbstractDocumentSource documentSource = new MavenDocumentSource(apiSource, new SystemStreamLog());
+        documentSource.loadDocuments();
+        OutputTemplate outputTemplate = new OutputTemplate(documentSource);
+        Assert.assertEquals(outputTemplate.getDataTypes().size(), 1);
+        Assert.assertEquals(outputTemplate.getDataTypes().iterator().next().getName(), "Child");
+    }
+
     @Test
     public void testWithFormat() throws Exception, GenerateException {
         apiSource.setWithFormatSuffix(true);

src/test/java/issue17/Child.java

@@ -0,0 +1,18 @@
+package issue17;
+
+/**
+ * Created with IntelliJ IDEA.
+ * User: kongchen
+ * Date: 7/31/13
+ */
+public class Child extends Parent{
+    private String name;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

src/test/java/issue17/IssueResource.java

@@ -0,0 +1,28 @@
+package issue17;
+
+import com.sun.jersey.api.NotFoundException;
+import com.wordnik.swagger.annotations.*;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+
+/**
+ * Created with IntelliJ IDEA.
+ * User: kongchen
+ * Date: 5/13/13
+ */
+@Path("/issue17")
+@Api(value = "/issue17", description = "For issue 17")
+@Produces({"application/json"})
+public class IssueResource {
+    @GET
+    @Path("/{carId}")
+    @ApiOperation(value = "For issue 17",responseClass = "issue17.Child")
+    public Response getIssue17()
+            throws NotFoundException {
+        return Response.noContent().build();
+    }
+}

src/test/java/issue17/Parent.java

@@ -0,0 +1,32 @@
+package issue17;
+
+/**
+ * Created with IntelliJ IDEA.
+ * User: kongchen
+ * Date: 7/31/13
+ */
+public class Parent {
+    protected Child child;
+    private String cannotsee;
+    protected String cansee;
+
+    public Child getChild(){
+        return child;
+    }
+
+    public String getCannotsee() {
+        return cannotsee;
+    }
+
+    public void setCannotsee(String cannotsee) {
+        this.cannotsee = cannotsee;
+    }
+
+    public String getCansee() {
+        return cansee;
+    }
+
+    public void setCansee(String cansee) {
+        this.cansee = cansee;
+    }
+}