Java setter for multiselect field in webwork action

I would like to get all values from multiselect in my form(webwork action).
For now i’m able to get only first value by setter with String parameter.
Is it possible to setup setter for all values of multipicker?

And i wonder how/where all form parameters are pasted to setters.

view:

<div class="field-group">
    <label for="csStatuses">$i18n.getText("csStatuses-label") <span class="aui-icon icon-required">(required)</span></label>
    <select class="multi-select" multiple="multiple" id="csStatuses" name="csStatuses">
        #foreach($status in $avaliableStatuses.entrySet())
        <option value="$status.key" #if($csApprovalStatuses==$status.key)selected #end>$status.value</option>
        #end
    </select>
    </div>
</div>

java:

public Map<String, String> getAvaliableStatuses(){
    return statusManager.getStatuses().stream().collect(Collectors.toMap(status -> status.getId(), status -> status.getName()));
}
public String getStatuses() {
return (String) pluginSettings.get("STATUSES");
}

public void setStatuses(String statuses) {
pluginSettings.put("STATUSES", Statuses);
}

cheers