public Emitter getEmitter(String emitterName) {
        Emitter emitter = emitterMap.get(emitterName);
        if (emitter == null) {
            throw new IllegalArgumentException("Can't find emitter for prefix: " + emitterName);
        }
        return emitter;
    }
Utility class that will apply the appropriate fetcher
to the fetcherString based on the prefix.
<p>
This does not allow multiple fetchers supporting the same prefix.
tika-core/src/main/java/org/apache/tika/pipes/emitter/EmitterManager.java