added NotSchema#describePropertiesTo()

Author: erosb

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

@@ -15,6 +15,8 @@
  */
 package org.everit.json.schema;
 
+import org.everit.json.schema.internal.JSONPrinter;
+
 import java.util.Objects;
 
 /**
@@ -86,4 +88,10 @@ public int hashCode() {
     protected boolean canEqual(Object other) {
         return other instanceof NotSchema;
     }
+
+    @Override
+    void describePropertiesTo(JSONPrinter writer) {
+        writer.key("not");
+        mustNotMatch.describeTo(writer);
+    }
 }

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

@@ -20,8 +20,7 @@
 import static org.junit.Assert.assertEquals;
 import org.junit.Test;
 
-public class
-NotSchemaTest {
+public class NotSchemaTest {
 
     @Test
     public void failure() {
@@ -45,4 +44,13 @@ public void equalsVerifier() {
                 .verify();
     }
 
+    @Test
+    public void toStringTest() {
+        NotSchema subject = NotSchema.builder()
+                .mustNotMatch(BooleanSchema.INSTANCE)
+                .build();
+        String actual = subject.toString();
+        assertEquals("{\"not\":{\"type\":\"boolean\"}}", actual);
+    }
+
 }