Deserialize empty JSON schemas

src/main/java/com/fasterxml/jackson/module/jsonSchema/JsonSchema.java

@@ -69,7 +69,7 @@
  * @author jphelan
  */
 @JsonInclude(JsonInclude.Include.NON_EMPTY)
-@JsonTypeInfo(use = Id.CUSTOM, include = As.PROPERTY, property = "type")
+@JsonTypeInfo(use = Id.CUSTOM, include = As.PROPERTY, property = "type", defaultImpl = AnySchema.class)
 @JsonTypeIdResolver(JsonSchemaIdResolver.class)
 public abstract class JsonSchema
 {

src/test/java/com/fasterxml/jackson/module/jsonSchema/NoTypeSchemaReadTest.java

@@ -0,0 +1,52 @@
+package com.fasterxml.jackson.module.jsonSchema;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatTypes;
+import com.fasterxml.jackson.module.jsonSchema.types.ArraySchema;
+
+public class NoTypeSchemaReadTest extends SchemaTestBase {
+    public void testNoTypeSchema() throws Exception {
+        String input = "{}";
+
+        ObjectMapper mapper = new ObjectMapper();
+        JsonSchema schema = mapper.readValue(input, JsonSchema.class);
+
+        assertEquals(JsonFormatTypes.ANY, schema.getType());
+    }
+
+    public void testNoTypeSingleItems() throws Exception {
+        String input = "{ \"type\": \"array\", \"items\": {} }";
+
+        ObjectMapper mapper = new ObjectMapper();
+        JsonSchema schema = mapper.readValue(input, JsonSchema.class);
+
+        assertTrue(schema instanceof ArraySchema);
+
+        ArraySchema.Items items = ((ArraySchema) schema).getItems();
+        assertNotNull(items);
+        assertTrue(items.isSingleItems());
+
+        JsonSchema itemsSchema = items.asSingleItems().getSchema();
+        assertNotNull(itemsSchema);
+        assertEquals(JsonFormatTypes.ANY, itemsSchema.getType());
+    }
+
+    public void testNoTypeArrayItems() throws Exception {
+        String input = "{ \"type\": \"array\", \"items\": [{}] }";
+
+        ObjectMapper mapper = new ObjectMapper();
+        JsonSchema schema = mapper.readValue(input, JsonSchema.class);
+
+        assertTrue(schema instanceof ArraySchema);
+
+        ArraySchema.Items items = ((ArraySchema) schema).getItems();
+        assertNotNull(items);
+        assertTrue(items.isArrayItems());
+
+        JsonSchema[] itemsSchemas = items.asArrayItems().getJsonSchemas();
+        assertNotNull(itemsSchemas);
+        assertEquals(itemsSchemas.length, 1);
+        assertNotNull(itemsSchemas[0]);
+        assertEquals(JsonFormatTypes.ANY, itemsSchemas[0].getType());
+    }
+}