@Override
    public IExportWriter startGateways() {
        validityCheckStart(GlobalElementsEnum.Gateways);
        lock(GlobalElementsEnum.Gateways);
        writeStartArray(GlobalElementsEnum.Gateways);
        return this;
    }
Constructor.

@param targetStream
@param logger logger used (and abused!) for
@throws IOException
manager/api/export-import/src/main/java/io/apiman/manager/api/exportimport/json/JsonExportWriter.java