diff --git a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/LinkVisitorContext.java b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/LinkVisitorContext.java
index 84a83fa..05dbec5 100644
--- a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/LinkVisitorContext.java
+++ b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/LinkVisitorContext.java
@@ -39,6 +39,7 @@ protected boolean isModel(JavaType type) {
         return type.getRawClass() != String.class
                 && !isBoxedPrimitive(type)
                 && !type.isPrimitive()
+                && !type.isEnumType()
                 && !type.isMapLikeType()
                 && !type.isCollectionLikeType();
     }
diff --git a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Mapper.java b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Mapper.java
index b5198a1..828e493 100644
--- a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Mapper.java
+++ b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Mapper.java
@@ -15,13 +15,16 @@
  */
 package io.gravitee.maven.plugins.json.schema.generator.mojo;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.PropertyName;
+import com.fasterxml.jackson.databind.introspect.Annotated;
+import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;
 import com.fasterxml.jackson.module.jsonSchema.JsonSchema;
 import com.fasterxml.jackson.module.jsonSchema.customProperties.HyperSchemaFactoryWrapper;
 import com.fasterxml.jackson.module.jsonSchema.factories.SchemaFactoryWrapper;
 import io.gravitee.maven.plugins.json.schema.generator.util.ClassFinder;
-import org.apache.maven.plugin.MojoExecutionException;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -49,6 +52,22 @@ public Mapper(Config config) {
         this.config = config;
     }
 
+    /**
+     * WRITE_ONLY fields are no output to the schema. This is incorrect.
+     * From https://stackoverflow.com/a/55064740/3351474
+     */
+    private class IgnoreJacksonWriteOnlyAccess extends JacksonAnnotationIntrospector {
+
+        @Override
+        public JsonProperty.Access findPropertyAccess(Annotated m) {
+            JsonProperty.Access access = super.findPropertyAccess(m);
+            if (access == JsonProperty.Access.WRITE_ONLY) {
+                return JsonProperty.Access.AUTO;
+            }
+            return access;
+        }
+    }
+
     /**
      * Generates JSON Schemas from the matched Class names
      *
@@ -58,21 +77,30 @@ public List<JsonSchema> generateJsonSchemas() {
         final List<JsonSchema> generatedSchemas = new ArrayList<>();
 
         ObjectMapper mapper = new ObjectMapper();
+        mapper.setAnnotationIntrospector(new IgnoreJacksonWriteOnlyAccess());
         SchemaFactoryWrapper schemaVisitor = new HyperSchemaFactoryWrapper();
         schemaVisitor.setVisitorContext(new LinkVisitorContext());
 
         for (String className : generateClassNames()) {
             try {
+                Class<?> _class = getClass().getClassLoader().loadClass(className);
                 try {
-                    mapper.acceptJsonFormatVisitor(mapper.constructType(
-                            getClass().getClassLoader().loadClass(className)
-                    ), schemaVisitor);
+                    mapper.acceptJsonFormatVisitor(mapper.constructType(_class), schemaVisitor);
                 } catch (JsonMappingException e) {
                     throw new GenerationException("Unable to format class " + className, e);
                 }
                 JsonSchema schema = schemaVisitor.finalSchema();
                 if (schema == null) {
-                    throw new IllegalArgumentException("Could not build schema or find any classes.");
+                    throw new IllegalArgumentException("Could not build schema for class "+className);
+                }
+                if (schema.getId() == null) {
+                    if (_class.isEnum()) {
+                        config.getLogger().info("Skipping enum class " + className + " (will be included directly in referenced schema)");
+                    }
+                    else {
+                        config.getLogger().warn("Ignoring schema for class " + className);
+                    }
+                    continue;
                 }
                 generatedSchemas.add(schema);
             } catch (GenerationException | ClassNotFoundException e) {
diff --git a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Output.java b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Output.java
index 2fe0070..203e548 100644
--- a/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Output.java
+++ b/src/main/java/io/gravitee/maven/plugins/json/schema/generator/mojo/Output.java
@@ -95,7 +95,7 @@ private void createJsonFile(JsonSchema schema) {
             config.getLogger().info("Created JSON Schema: " + outputPath.normalize().toAbsolutePath().toString());
         } catch (JsonProcessingException e) {
             config.getLogger().warn("Unable to display schema " + schema.getId(), e);
-        } catch (IOException e) {
+        } catch (Exception e) {
             config.getLogger().warn("Unable to write Json file for schema " + schema.getId(), e);
         }
     }
diff --git a/src/test/java/io/gravitee/maven/plugins/json/schema/generator/mojo/MapperTest.java b/src/test/java/io/gravitee/maven/plugins/json/schema/generator/mojo/MapperTest.java
index ec557e6..0aa95c7 100644
--- a/src/test/java/io/gravitee/maven/plugins/json/schema/generator/mojo/MapperTest.java
+++ b/src/test/java/io/gravitee/maven/plugins/json/schema/generator/mojo/MapperTest.java
@@ -26,6 +26,7 @@
 
 import java.io.File;
 import java.util.Arrays;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 
@@ -69,7 +70,7 @@ public void testGenerateJsonSchemasWithNoBean() throws Exception {
         mapper = new Mapper(new Config(new Globs(Arrays.asList("NoBean.class"), null), BUILD_DIRECTORY, null, LOG));
 
         List<JsonSchema> schemas = mapper.generateJsonSchemas();
-        Assert.assertFalse(schemas.isEmpty());
+        Assert.assertTrue(schemas.isEmpty());
     }
 
     @Test
@@ -94,14 +95,9 @@ public void testGenerateJsonSchemasWithBeanByUsingExternalDependency() throws Ex
         Assert.assertEquals(1, properties.size());
 
         JsonSchema stringSchema = properties.get("jsonFormatTypes");
-        Assert.assertEquals(JsonFormatTypes.OBJECT, stringSchema.getType());
-        /*
-        Assert.assertEquals(JsonFormatTypes.OBJECT, stringSchema.getType());
-        Assert.assertEquals(
-                "jsonFormatTypes",
-                stringSchema.getId().substring(stringSchema.getId().lastIndexOf(":") + 1, stringSchema.getId().length())
-        );
-        */
+        Assert.assertEquals(JsonFormatTypes.STRING, stringSchema.getType());
+        Assert.assertEquals(new HashSet<>(Arrays.asList("string", "number", "integer",
+                "boolean", "object", "array", "null", "any")), stringSchema.asValueTypeSchema().getEnums());
     }