@Test
public void test() {
List<Sensor> sensorMongoList = Lists.newArrayList();
Sensor sensor = new Sensor();
sensor.setId("123123");
sensor.setNum("1");
sensorMongoList.add(sensor);
Sensor sensorTwo = new Sensor();
sensorTwo.setId("3423423");
sensorTwo.setNum("2");
sensorMongoList.add(sensorTwo);
Sensor sensor1 = sensorMongoList.stream().max(Comparator.comparing(Sensor::getNum)).get();
String num = sensor1.getNum();
num = String.valueOf(Integer.parseInt(num) + 1);
System.err.println(num);
}

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