Add test case and configurable in JsonStream.java

Author: caoli5288

src/main/java/com/jsoniter/output/JsonStream.java

@@ -499,6 +499,12 @@ public static void setIndentionStep(int indentionStep) {
         JsoniterSpi.setCurrentConfig(newConfig);
     }
 
+    public static void setOmitZero(boolean omitZero) {
+        Config newConfig = JsoniterSpi.getDefaultConfig().copyBuilder().omitZero(omitZero).build();
+        JsoniterSpi.setDefaultConfig(newConfig);
+        JsoniterSpi.setCurrentConfig(newConfig);
+    }
+
     public static void registerNativeEncoder(Class clazz, Encoder.ReflectionEncoder encoder) {
         CodegenImplNative.NATIVE_ENCODERS.put(clazz, encoder);
     }

src/test/java/com/jsoniter/TestObject.java

@@ -3,6 +3,9 @@
 import com.jsoniter.annotation.JsonProperty;
 import com.jsoniter.any.Any;
 import com.jsoniter.fuzzy.MaybeEmptyArrayDecoder;
+import com.jsoniter.output.EncodingMode;
+import com.jsoniter.output.JsonStream;
+import com.jsoniter.spi.Config;
 import com.jsoniter.spi.EmptyExtension;
 import com.jsoniter.spi.JsonException;
 import com.jsoniter.spi.JsoniterSpi;
@@ -235,4 +238,26 @@ public void test_object_lazy_any_to_string() {
         any.asMap().put("field4", Any.wrap(4));
         assertEquals("{\"field1\":1,\"field3\":3,\"field2\":2,\"field4\":4}", any.toString());
     }
+
+    public static class TOmitZero {
+
+        public int i;
+        public long l = 1;
+        public float f;
+        public double d = 1;
+    }
+
+    public void test_omit_zero() {
+        Config def = JsoniterSpi.getCurrentConfig();
+        try {
+            JsonStream.setOmitZero(true);
+            assertEquals("{\"l\":1,\"d\":1}", JsonStream.serialize(new TOmitZero()));
+
+            JsonStream.setMode(EncodingMode.DYNAMIC_MODE);
+            assertEquals("{\"l\":1,\"d\":1}", JsonStream.serialize(new TOmitZero()));
+        } finally {
+            JsoniterSpi.setDefaultConfig(def);
+            JsoniterSpi.setCurrentConfig(def);
+        }
+    }
 }