Also enable model extensions in existing keys

Use a LinkedHashMap to ensure that fields from model sub-classes are
preferred over fields from base classes.

src/main/java/org/raml/parser/builder/TupleBuilderFactory.java

@@ -18,7 +18,7 @@
 import java.lang.reflect.Field;
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
-import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -38,7 +38,7 @@ public class TupleBuilderFactory extends AbstractFactory
     public void addBuildersTo(Class<?> pojoClass, TupleBuilder parent)
     {
         final List<Field> declaredFields = ReflectionUtils.getInheritedFields(pojoClass);
-        final Map<String, TupleBuilder<?, ?>> innerBuilders = new HashMap<String, TupleBuilder<?, ?>>();
+        final Map<String, TupleBuilder<?, ?>> innerBuilders = new LinkedHashMap<String, TupleBuilder<?, ?>>();
         for (Field declaredField : declaredFields)
         {
             Scalar scalar = declaredField.getAnnotation(Scalar.class);

src/test/java/org/raml/parser/visitor/RamlDocumentBuilderTestCase.java

@@ -16,11 +16,19 @@
 package org.raml.parser.visitor;
 
 import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.notNullValue;
 import static org.junit.Assert.assertThat;
 
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
 import org.junit.Test;
 import org.raml.model.Raml;
+import org.raml.model.SecurityScheme;
+import org.raml.parser.annotation.Mapping;
 import org.raml.parser.annotation.Scalar;
+import org.raml.parser.annotation.Sequence;
 import org.raml.parser.builder.AbstractRamlTestCase;
 
 public class RamlDocumentBuilderTestCase extends AbstractRamlTestCase
@@ -34,6 +42,15 @@ public void parseExtendedModel()
         assertThat(raml.getExtension(), is("additional data")); // non-standard property
     }
 
+    @Test
+    public void parseModelWithExtensionInExistingKey()
+    {
+        RamlExt2 raml = (RamlExt2) new RamlDocumentBuilder(RamlExt2.class).build("org/raml/parser/visitor/extended.yaml");
+        SecuritySchemeExt scheme = raml.getSecuritySchemesExt().get(0).get("extended");
+        assertThat(scheme.getDescription(), is(notNullValue()));
+        assertThat(scheme.getExtension().get("key1"), is("foo"));
+    }
+
     public static class RamlExt extends Raml
     {
         private static final long serialVersionUID = 533345138584973337L;
@@ -49,4 +66,36 @@ public void setExtension(String extension) {
             this.extension = extension;
         }
     }
+
+    public static class RamlExt2 extends Raml
+    {
+        private static final long serialVersionUID = 1451208177799874616L;
+
+        @Sequence(alias = "securitySchemes")
+        private List<Map<String, SecuritySchemeExt>> securitySchemesExt = new ArrayList<Map<String, SecuritySchemeExt>>();
+
+        public List<Map<String, SecuritySchemeExt>> getSecuritySchemesExt() {
+            return securitySchemesExt;
+        }
+
+        public void setSecuritySchemesExt(List<Map<String, SecuritySchemeExt>> securitySchemesExt) {
+            this.securitySchemesExt = securitySchemesExt;
+        }
+    }
+
+    public static class SecuritySchemeExt extends SecurityScheme
+    {
+        private static final long serialVersionUID = -7059558387326732177L;
+
+        @Mapping
+        private Map<String,String> extension;
+
+        public Map<String, String> getExtension() {
+            return extension;
+        }
+
+        public void setExtension(Map<String, String> extension) {
+            this.extension = extension;
+        }
+    }
 }

src/test/resources/org/raml/parser/visitor/extended.yaml

@@ -1,3 +1,10 @@
 #%RAML 0.8
 title: extended model
 extension: additional data
+
+securitySchemes:
+    - extended:
+          description: Security schema documentation
+          extension:
+              key1: foo
+              key2: bar