static final public void error(String msg) {
        // error cannot be disabled
        getTarget().println(SLF4J_ERROR_PREFIX + msg);
    }
Report an internal message of level "ERROR". Message text is prefixed with the string "SLF4J(E)",
with (E)  standing as a shorthand for ERROR.

<p>Messages of level ERROR are always enabled.

@param msg the message text
slf4j-api/src/main/java/org/slf4j/helpers/Reporter.java