Add exception for argument mismatch in contructor

Author: shadromani

src/main/java/com/maxmind/db/Decoder.java

@@ -439,6 +439,17 @@ private <T> Object decodeMapIntoObject(int size, Class<T> cls)
                 InvocationTargetException e) {
             throw new DeserializationException("Error creating object: " + e.getMessage(), e);
         }
+        catch (IllegalArgumentException e){
+            StringBuilder sbErrors = new StringBuilder();  
+            for (String key : parameterIndexes.keySet()) {
+                int index= parameterIndexes.get(key);
+                if ( !parameters[index].getClass().isAssignableFrom( parameterTypes[index])){
+                    sbErrors.append(" argument type mismatch in " + key + " MMDB Type: "+ parameters[index].getClass().getCanonicalName()
+                    +" Java Type: " +parameterTypes[index].getCanonicalName());
+                }              
+            }
+            throw new DeserializationException("Error creating object of type: " + cls.getSimpleName() + " - " + sbErrors.toString(), e);
+        }
     }
 
     private static <T> Constructor<T> findConstructor(Class<T> cls)

src/main/java/com/maxmind/db/Reader.java

@@ -177,7 +177,12 @@ record = this.readNode(buffer, record, bit);
         T dataRecord = null;
         if (record > nodeCount) {
             // record is a data pointer
-            dataRecord = this.resolveDataPointer(buffer, record, cls);
+            try {
+                dataRecord = this.resolveDataPointer(buffer, record, cls);
+            } catch (DeserializationException exception) {
+                throw new DeserializationException("Error getting record for IP " + ipAddress.toString(), exception);
+            }
+
         }
 
         return new DatabaseRecord<>(dataRecord, ipAddress, pl);

src/test/java/com/maxmind/db/ReaderTest.java

@@ -567,6 +567,38 @@ public TestModelSubdivision(
         }
     }
 
+    @Test
+    public void testDecodeWrongTypeSubdivisions() throws IOException {
+        this.testReader = new Reader(getFile("GeoIP2-City-Test.mmdb"));
+        DeserializationException ex = assertThrows(DeserializationException.class,
+        () -> this.testReader.get( InetAddress.getByName("2.125.160.216"),TestWrongModelSubdivisions.class));
+        assertThat(ex.getMessage(), containsString("Error getting record for IP"));
+    }
+
+    static class TestWrongModelSubdivisions {
+        List<TestWrongModelSubdivision> subdivisions;
+
+        @MaxMindDbConstructor
+        public TestWrongModelSubdivisions (
+            @MaxMindDbParameter(name="subdivisions")
+            List<TestWrongModelSubdivision> subdivisions
+        ) {
+            this.subdivisions = subdivisions;
+        }
+    }
+
+    static class TestWrongModelSubdivision {
+        Integer uint16Field;
+        @MaxMindDbConstructor
+        public TestWrongModelSubdivision(
+            @MaxMindDbParameter(name="iso_code")
+            Integer uint16Field
+            ) {
+            this.uint16Field = uint16Field;
+            ;
+        }
+    }
+
     @Test
     public void testDecodeConcurrentHashMap() throws IOException {
         this.testReader = new Reader(getFile("GeoIP2-City-Test.mmdb"));
@@ -775,7 +807,7 @@ public void voidTestMapKeyIsString() throws IOException {
                 TestModelInvalidMap.class
             )
         );
-        assertEquals("Map keys must be strings.", ex.getMessage());
+        assertEquals("Error getting record for IP /2.125.160.216", ex.getMessage());
     }
 
     static class TestModelInvalidMap {