CodeMirror: CodeMirror is a JavaScript library that can be used to create a relatively pleasant editor interface for code-like content - computer programs, HTML markup, and similar. If a parser has been written for the language you are editing (see below for a list of supported languages), the code will be colored, and the editor will help you with indentation.
This Vaadin add-on integrates CodeMirror as a TextField component.
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NOTE: The implementation is still experimental. Some of the features like keyboard focus control, line-based API are missing.