Coordinates is an object with an array

Ensure that the array is of a fixed length, add tests to check for that.

1 files changed, 43 insertions, 5 deletions

diff --git a/src/data/ValidatingJsonDeserializer.java b/src/data/ValidatingJsonDeserializer.java
index 5dca3bd..431622b 100644
--- a/src/data/ValidatingJsonDeserializer.java
+++ b/src/data/ValidatingJsonDeserializer.java
@@ -31,7 +31,8 @@ public class ValidatingJsonDeserializer<T> implements JsonDeserializer<T> {
         return obj;
     }
 
-    void checkObject(String path, JsonElement je, Class type) {
+    void checkObject(String path, JsonElement je, Class type)
+            throws JsonParseException {
         JsonObject jsonObj = je.getAsJsonObject();
         for (Field f : type.getDeclaredFields()) {
             JsonElement val = jsonObj.get(f.getName());
@@ -52,12 +53,33 @@ public class ValidatingJsonDeserializer<T> implements JsonDeserializer<T> {
         }
     }
 
-    private void tryValidateProperty(String path, JsonElement je, Field f) {
+    private void tryValidateProperty(String path, JsonElement je, Field f)
+            throws JsonParseException {
+        Class<?> type = f.getType();
         // assume that this annotation is only applied to objects
         Validator v = f.getAnnotation(Validator.class);
+        ArrayValidator av = f.getAnnotation(ArrayValidator.class);
         path += f.getName();
+        if (av != null) {
+            if (!type.isArray()) {
+                throw new RuntimeException("Invalid " + av.getClass().getName()
+                        + " + annotation for " + path);
+            }
+            if (!je.isJsonArray()) {
+                throw new JsonParseException("Expected array: " + path);
+            }
+            JsonArray ja = je.getAsJsonArray();
+            int minLen = av.minLen(), maxLen = av.maxLen();
+            if (minLen >= 0 && ja.size() < minLen) {
+                throw new JsonParseException("Array smaller than "
+                        + minLen + ": " + path);
+            }
+            if (maxLen >= 0 && ja.size() > maxLen) {
+                throw new JsonParseException("Array larger than "
+                        + maxLen + ": " + path);
+            }
+        }
         if (v != null) {
-            Class<?> type = f.getType();
             if (type.isArray()) {
                 // the class expects an array, so the value must have one too.
                 if (!je.isJsonArray()) {
@@ -84,9 +106,25 @@ public class ValidatingJsonDeserializer<T> implements JsonDeserializer<T> {
      */
     @Retention(RetentionPolicy.RUNTIME)
     @Target(ElementType.FIELD)
-    public @interface Validator {
+    public @interface ArrayValidator {
 
-        Class deserializer() default ValidatingJsonDeserializer.class;
+        /**
+         * @return Minimal length for array types (-1 if not checked).
+         */
+        int minLen() default -1;
+
+        /**
+         * @return Maximum length for array types (-1 if not checked).
+         */
+        int maxLen() default -1;
+    }
+
+    /**
+     * Marks a member as object that should be validated too.
+     */
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.FIELD)
+    public @interface Validator {
     }
 
     /**