See http://docs.oracle.com/javafx/2/api/javafx/fxml/FXMLLoader.html#setRoot(java.lang.Object)
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The value passed to this method is used as the value of the <fx:root%gt; tag. This method must be called prior to loading the document when using <fx:root%gt;.
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The value passed to this method is used as the value of the <fx:root%gt; tag. This method must be called prior to loading the document when using <fx:root%gt;.
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