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# Writing Native JavaScript Methods

JSNI methods are declared `native` and contain JavaScript code in a specially formatted comment block between the end of the parameter list and the trailing semicolon. A JSNI comment block begins with the exact token `/*-{` and ends with the exact token `}-*/`. JSNI methods are be called just like any normal Java method. They can be static or instance methods.

## Example

    public static native void alert(String msg) /*-{
      $wnd.alert(msg);
    }-*/;

Tip
In hosted mode, you can set a breakpoint on the source line containing the opening brace of a JSNI method, allowing you to see invocation arguments.