Fix an issue with parsing null values. Null objects are now stored as empty objects, rather than as true null values

Author: stevenlagoy

pom.xml

@@ -4,7 +4,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.github.stevenlagoy</groupId>
     <artifactId>json-java-objectifier</artifactId>
-    <version>1.0.3</version>
+    <version>1.0.4</version>
     <packaging>jar</packaging>
     <name>JSON Java Objectifier</name>
     <description>Java tools for converting JSON into typed object structures</description>

src/main/java/core/JSONObject.java

@@ -62,7 +62,7 @@ private static boolean isValidJsonType(Object value) {
             value instanceof JSONObject ||
             value instanceof List<?> ||
             value instanceof Boolean ||
-            value == null
+            value instanceof Object
         );
     }
 

src/main/java/core/JSONStringifier.java

@@ -56,7 +56,7 @@ public static String stringifyValue(Object value, Class<?> type) {
     public static String stringifyValue(Object value) {
         if (value instanceof String) return "\"" + stringifyEscape((String) value) + "\"";
         if (value instanceof Number || value instanceof Boolean) return value.toString();
-        if (value == null) return "null";
+        if (value instanceof Object) return "null";
         else throw new IllegalArgumentException("Unsupported JSON value: " + value);
     }
 

src/tests/java/StringifierTests.java

@@ -23,7 +23,7 @@ public void stringifyValue() {
         assertEquals("\"hello\"", JSONStringifier.stringifyValue("hello"));
         assertEquals("42", JSONStringifier.stringifyValue(42));
         assertEquals("true", JSONStringifier.stringifyValue(true));
-        assertEquals("null", JSONStringifier.stringifyValue(null));
+        assertEquals("null", JSONStringifier.stringifyValue(new Object()));
 
         // Test with type information
         List<Integer> numbers = new ArrayList<>();

src/tests/java/Tests.java

@@ -10,6 +10,17 @@
 
 public class Tests {
 
+    @Test
+    public void testFileWithNulls() {
+        Path expectedPath = Path.of("src", "tests", "java", "data", "test7", "expected7.out");
+        Path testPath = Path.of("src", "tests", "java", "data", "test7", "test7.json");
+
+        String expected = String.join("\n", FileOperations.readFile(expectedPath));
+        String actual = JSONProcessor.processJson(testPath).toString();
+
+        assertEquals(expected, actual);
+    }
+
     @Test
     public void testVeryLargeFile() {
 

src/tests/java/data/test7/expected7.out

@@ -0,0 +1,52 @@
+"test7" : {
+	"FIPS" : "02016",
+	"name" : "Aleutians West Census Area",
+	"state" : "Alaska",
+	"county_seat" : null,
+	"population" : 5619,
+	"population_desity" : 1.5,
+	"pop_change_rate" : 5.8,
+	"square_mileage" : 3682.18,
+	"white_population" : 2004,
+	"black_population" : 332,
+	"native_indian_population" : 857,
+	"asian_population" : 1606,
+	"pacific_islander_population" : 103,
+	"hispanic_population" : 726,
+	"other_race_ethnicity_population" : 348,
+	"multiple_race_population" : 311,
+	"pop_male" : 3723,
+	"pop_female" : 1838,
+	"pop_0to4" : 205,
+	"pop_5to9" : 227,
+	"pop_10to14" : 226,
+	"pop_15to19" : 249,
+	"pop_20to24" : 334,
+	"pop_25to34" : 972,
+	"pop_35to44" : 1137,
+	"pop_45to54" : 1232,
+	"pop_55to64" : 786,
+	"pop_65to74" : 157,
+	"pop_75to84" : 31,
+	"pop_85to120" : 5,
+	"median_age" : 40.7,
+	"median_age_male" : 41.0,
+	"median_age_female" : 39.9,
+	"number_households" : 1212,
+	"average_household_size" : 2.49,
+	"number_households_singleM_wo_child" : 288,
+	"number_households_singleF_wo_child" : 105,
+	"number_households_married_w_child" : 288,
+	"number_households_married_wo_child" : 220,
+	"number_households_singleM_w_child" : 59,
+	"number_households_singleF_w_child" : 86,
+	"number_families" : 711,
+	"average_family_size" : 3.18,
+	"housing_units" : 1212,
+	"housing_vacant" : 717,
+	"owner_occupied_housing" : 391,
+	"renter_occupied_housing" : 821,
+	"number_farms" : -99,
+	"average_farm_acreage" : -99,
+	"total_crop_acreage" : -99
+}

src/tests/java/data/test7/test7.json

@@ -0,0 +1,52 @@
+{
+    "FIPS" : "02016",
+    "name" : "Aleutians West Census Area",
+    "state" : "Alaska",
+    "county_seat" : null,
+    "population" : 5619,
+    "population_desity" : 1.5,
+    "pop_change_rate" : 5.8,
+    "square_mileage" : 3682.18,
+    "white_population" : 2004,
+    "black_population" : 332,
+    "native_indian_population" : 857,
+    "asian_population" : 1606,
+    "pacific_islander_population" : 103,
+    "hispanic_population" : 726,
+    "other_race_ethnicity_population" : 348,
+    "multiple_race_population" : 311,
+    "pop_male" : 3723,
+    "pop_female" : 1838,
+    "pop_0to4" : 205,
+    "pop_5to9" : 227,
+    "pop_10to14" : 226,
+    "pop_15to19" : 249,
+    "pop_20to24" : 334,
+    "pop_25to34" : 972,
+    "pop_35to44" : 1137,
+    "pop_45to54" : 1232,
+    "pop_55to64" : 786,
+    "pop_65to74" : 157,
+    "pop_75to84" : 31,
+    "pop_85to120" : 5,
+    "median_age" : 40.7,
+    "median_age_male" : 41.0,
+    "median_age_female" : 39.9,
+    "number_households" : 1212,
+    "average_household_size" : 2.49,
+    "number_households_singleM_wo_child" : 288,
+    "number_households_singleF_wo_child" : 105,
+    "number_households_married_w_child" : 288,
+    "number_households_married_wo_child" : 220,
+    "number_households_singleM_w_child" : 59,
+    "number_households_singleF_w_child" : 86,
+    "number_families" : 711,
+    "average_family_size" : 3.18,
+    "housing_units" : 1212,
+    "housing_vacant" : 717,
+    "owner_occupied_housing" : 391,
+    "renter_occupied_housing" : 821,
+    "number_farms" : -99,
+    "average_farm_acreage" : -99,
+    "total_crop_acreage" : -99
+}