support gson serializeNulls

taowen · taowen · commit aa3db15aa213 · 2017-06-04T23:35:47.000+08:00
diff --git a/src/main/java/com/jsoniter/extra/GsonCompatibilityMode.java b/src/main/java/com/jsoniter/extra/GsonCompatibilityMode.java
@@ -21,12 +21,18 @@ protected Builder builder() {
 
     public static class Builder extends Config.Builder {
         private boolean excludeFieldsWithoutExposeAnnotation = false;
+        private boolean serializeNulls = false;
 
         public Builder excludeFieldsWithoutExposeAnnotation() {
             excludeFieldsWithoutExposeAnnotation = true;
             return this;
         }
 
+        public Builder serializeNulls() {
+            serializeNulls = true;
+            return this;
+        }
+
         public GsonCompatibilityMode build() {
             return (GsonCompatibilityMode) super.build();
         }
@@ -44,21 +50,28 @@ public boolean equals(Object o) {
 
             Builder builder = (Builder) o;
 
-            return excludeFieldsWithoutExposeAnnotation == builder.excludeFieldsWithoutExposeAnnotation;
+            if (excludeFieldsWithoutExposeAnnotation != builder.excludeFieldsWithoutExposeAnnotation) return false;
+            return serializeNulls == builder.serializeNulls;
         }
 
         @Override
         public int hashCode() {
             int result = super.hashCode();
             result = 31 * result + (excludeFieldsWithoutExposeAnnotation ? 1 : 0);
+            result = 31 * result + (serializeNulls ? 1 : 0);
             return result;
         }
     }
 
     @Override
     public void updateClassDescriptor(ClassDescriptor desc) {
-        super.updateClassDescriptor(desc);
         removeGetterAndSetter(desc);
+        for (Binding binding : desc.allEncoderBindings()) {
+            if (builder().serializeNulls) {
+                binding.shouldOmitNull = false;
+            }
+        }
+        super.updateClassDescriptor(desc);
     }
 
     private void removeGetterAndSetter(ClassDescriptor desc) {
diff --git a/src/test/java/com/jsoniter/output/TestGson.java b/src/test/java/com/jsoniter/output/TestGson.java
@@ -73,4 +73,16 @@ public void test_excludeFieldsWithoutExposeAnnotation() {
         output = JsonStream.serialize(config, obj);
         assertEquals("{}", output);
     }
+
+    public void test_serializeNulls() {
+        TestObject4 obj = new TestObject4();
+        Gson gson = new GsonBuilder().serializeNulls().create();
+        String output = gson.toJson(obj);
+        assertEquals("{\"field1\":null}", output);
+
+        GsonCompatibilityMode config = new GsonCompatibilityMode.Builder()
+                .serializeNulls().build();
+        output = JsonStream.serialize(config, obj);
+        assertEquals("{\"field1\":null}", output);
+    }
 }
