BUG OF THE MONTH | Comparing a string with an object

V6058 The ‘equals’ function compares objects of incompatible types: String, ModelNode. JaxrsIntegrationProcessor.java(563)

// Send value to RESTEasy only if it's not null, empty string, or the 
// default value.

private boolean isTransmittable(AttributeDefinition attribute,
                                ModelNode modelNode) {
  if (modelNode == null || ModelType
      .UNDEFINED.equals(modelNode.getType())) {
    return false;
  }
  String value = modelNode.asString();
  if ("".equals(value.trim())) {
    return false;
  }
  return !value.equals(attribute.getDefaultValue());        
}

A string is compared with an object – and such comparison always returns false. That is, even if the value modelNode is equal to attribute.getDefaultValue(), the method will return false anyway and the value will be permitted for sending – contrary to what the comment says.

It seems the programmer forgot to call the asString() method to have attribute.getDefaultValue() represented as a string. This is what the fixed version could look like:

return !value.equals(attribute.getDefaultValue().asString());

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