@CanIgnoreReturnValue
    public CasEvent put(final String key, final String value) {
        if (StringUtils.isBlank(value)) {
            this.properties.remove(key);
        } else {
            this.properties.put(key, value);
        }
        return this;
    }
Put property.

@param key   the key
@param value the value
@return the cas event
api/cas-server-core-api-events/src/main/java/org/apereo/cas/support/events/dao/CasEvent.java