private Map<Class<? extends WaveBean>, WaveBean> getWaveBeanMap() {
        if (this.waveBeanMap == null) {
            this.waveBeanMap = new HashMap<>();
        }
        return this.waveBeanMap;
    }
private Map < Class < ? extends WaveBean > , WaveBean > getWaveBeanMap ( ) { if ( this . waveBeanMap == null ) { this . waveBeanMap = new HashMap < > ( ) ; } return this . waveBeanMap ; }
Get the Wave Bean map. Create it if it hasn't been done before.

@return the wave bean map never null