ObjectSchema#describePropertiesTo() improvements: adding support to the following keywords:

    * minProperties, maxProperties
    * required
    * additionalProperties (schema)
    * dependencies (property)

Author: erosb

core/src/main/java/org/everit/json/schema/ObjectSchema.java

@@ -462,16 +462,42 @@ public int hashCode() {
 
     @Override
     void describePropertiesTo(JSONPrinter writer) {
-        writer.key("type").value("object");
+        if (requiresObject) {
+            writer.key("type").value("object");
+        }
         if (!propertySchemas.isEmpty()) {
             writer.key("properties");
             writer.object();
             propertySchemas.entrySet().forEach(entry -> {
-                        writer.key(entry.getKey());
-                        entry.getValue().describeTo(writer);
-                    });
+                writer.key(entry.getKey());
+                entry.getValue().describeTo(writer);
+            });
             writer.endObject();
         }
+        writer.ifPresent("minProperties", minProperties);
+        writer.ifPresent("maxProperties", maxProperties);
+        if (!requiredProperties.isEmpty()) {
+            writer.key("required").value(requiredProperties);
+        }
+        if (schemaOfAdditionalProperties != null) {
+            writer.key("additionalProperties");
+            schemaOfAdditionalProperties.describeTo(writer);
+        }
+        if (!propertyDependencies.isEmpty()) {
+            describePropertyDependenciesTo(writer);
+        }
+    }
+
+    private void describePropertyDependenciesTo(JSONPrinter writer) {
+        writer.key("dependencies");
+        writer.object();
+        propertyDependencies.entrySet().forEach(entry -> {
+            writer.key(entry.getKey());
+            writer.array();
+            entry.getValue().forEach(writer::value);
+            writer.endArray();
+        });
+        writer.endObject();
     }
 
     @Override

core/src/test/java/org/everit/json/schema/ObjectSchemaTest.java

@@ -30,6 +30,8 @@ public class ObjectSchemaTest {
 
     private static final JSONObject OBJECTS  = ResourceLoader.DEFAULT.readObj("objecttestcases.json");
 
+    private ResourceLoader loader = ResourceLoader.DEFAULT;
+
     @Test
     public void additionalPropertiesOnEmptyObject() {
         ObjectSchema.builder()
@@ -283,15 +285,26 @@ public void equalsVerifier() {
 
     @Test
     public void toStringTest() {
-        JSONObject rawSchemaJson = ResourceLoader.DEFAULT.readObj("tostring/objectschema.json");
+        JSONObject rawSchemaJson = loader.readObj("tostring/objectschema.json");
+        String actual = SchemaLoader.load(rawSchemaJson).toString();
+        assertTrue(ObjectComparator.deepEquals(rawSchemaJson, new JSONObject(actual)));
+    }
+
+    @Test
+    public void toStringNoExplicitType() {
+        JSONObject rawSchemaJson = loader.readObj("tostring/objectschema.json");
+        rawSchemaJson.remove("type");
         String actual = SchemaLoader.load(rawSchemaJson).toString();
         assertTrue(ObjectComparator.deepEquals(rawSchemaJson, new JSONObject(actual)));
     }
 
+    @Test @Ignore
+    public void toStringNoAdditionalProperties() {
 
+    }
 
     @Test @Ignore
-    public void toStringNoExplicitType() {
+    public void toStringSchemaDependencies() {
 
     }
 }

core/src/test/resources/org/everit/jsonvalidator/tostring/objectschema.json

@@ -1,8 +1,22 @@
 {
-  "type" : "object",
+  "type": "object",
   "properties": {
-    "numprop" : {
-      "type" : "number"
+    "numprop": {
+      "type": "number"
     }
+  },
+  "minProperties": 3,
+  "maxProperties": 4,
+  "required": [
+    "numprop"
+  ],
+  "additionalProperties": {
+    "type": "boolean"
+  },
+  "dependencies": {
+    "prop1": [
+      "prop2",
+      "prop3"
+    ]
   }
 }