Understanding UTF-8

If you use non-English characters or data in your business services, you must configure JDeveloper to support UTF-8. When you set up preferences and default project properties to support UTF-8 encoding, all existing projects and any new projects that you add show the preferences and the default project property as UTF-8 encoding. You must individually set up each project where you have non-English characters or data to show UTF-8 as the encoding value.

You are not required to set up UTF-8 encoding when you test web services.