In the below code, Why sonarqube is not finding possible null pointer exception in "updateData" method?
public class PropertyObject extends LinkedHashMap<String, Object> {
/**
* Unique serialization id.
*/
private static final long serialVersionUID = 4789053897514939L;
}
public class BaseObject extends PropertyObject {
#JsonProperty("_id")
public String getId() {
return String.valueOf(this.get("_id"));
}
#JsonProperty("_id")
public void setId(Object id) {
this.put("_id", String.valueOf(id));
}
public String getName() {
return (String) this.get("name");
}
public void setName(String name) {
this.put("name", name);
}
}
private void updateData(BaseObject baseObject) {
List<Map<String, String>> link = (List<Map<String, String>>) baseObject.get("ratioMap");
for (Map<String, String> linkmap : link) {
}
}
}
I can see potential null pointer exception in updateData method in line number 2.
Is there any way by which I can make sonarqube to find these issues by itself?
First of all Sonar is a static code analysis tool. It depends on simple declarations to look for possible NPEs. Second I assume that you have an active rule for detecting possible NullPointer dereferences.
Last but not least I think that it would not detect NPEs in private methods which is not called...
Related
I have a Money class with factory methods for numeric and String values. I would like to use it as a property of my input Pojos.
I created some Converters for it, this is the String one:
#Component
public class StringMoneyConverter implements Converter<String, Money> {
#Override
public Money convert(String source) {
return Money.from(source);
}
}
My testing Pojo is very simple:
public class MoneyTestPojo {
private Money value;
//getter and setter ommited
}
I have an endpoint which expects a Pojo:
#PostMapping("/pojo")
public String savePojo(#RequestBody MoneyTestPojo pojo) {
//...
}
Finally, this is the request body:
{
value: "100"
}
I have the following error when I try this request:
JSON parse error: Cannot construct instance of
br.marcellorvalle.Money (although at least one Creator
exists): no String-argument constructor/factory method to deserialize
from String value ('100'); nested exception is
com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot
construct instance of br.marcellorvalle.Money (although at
least one Creator exists): no String-argument constructor/factory
method to deserialize from String value ('100')\n at [Source:
(PushbackInputStream); line: 8, column: 19] (through reference chain:
br.marcellorvalle.MoneytestPojo[\"value\"])",
If I change Money and add a constructor which receives a String this request works but I really need a factory method as I have to deliver special instances of Money on specific cases (zeros, nulls and empty strings).
Am I missing something?
Edit: As asked, here goes the Money class:
public class Money {
public static final Money ZERO = new Money(BigDecimal.ZERO);
private static final int PRECISION = 2;
private static final int EXTENDED_PRECISION = 16;
private static final RoundingMode ROUNDING = RoundingMode.HALF_EVEN;
private final BigDecimal amount;
private Money(BigDecimal amount) {
this.amount = amount;
}
public static Money from(float value) {
return Money.from(BigDecimal.valueOf(value));
}
public static Money from(double value) {
return Money.from(BigDecimal.valueOf(value));
}
public static Money from(String value) {
if (Objects.isNull(value) || "".equals(value)) {
return null;
}
return Money.from(new BigDecimal(value));
}
public static Money from(BigDecimal value) {
if (Objects.requireNonNull(value).equals(BigDecimal.ZERO)) {
return Money.ZERO;
}
return new Money(value);
}
//(...)
}
Annotating your factory method with #JsonCreator (from the com.fasterxml.jackson.annotation package) will resolve the issue:
#JsonCreator
public static Money from(String value) {
if (Objects.isNull(value) || "".equals(value)) {
return null;
}
return Money.from(new BigDecimal(value));
}
I just tested it, and it worked for me. Rest of your code looks fine except for the sample request (value should be in quotes), but I guess that's just a typo.
Update 1:
If you're unable to make changes to the Money class, I can think of another option - a custom Jackson deserializer:
public class MoneyDeserializer extends StdDeserializer<Money> {
private static final long serialVersionUID = 0L;
public MoneyDeserializer() {
this(null);
}
public MoneyDeserializer(Class<?> vc) {
super(vc);
}
#Override
public Money deserialize(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException {
JsonNode node = jp.getCodec().readTree(jp);
String value = node.textValue();
return Money.from(value);
}
}
Just register it with your ObjectMapper.
It seems that using the org.springframework.core.convert.converter.Converter only works if the Money class is a "#PathVariable" in the controller.
I finally solved it using the com.fasterxml.jackson.databind.util.StdConverter class:
I created the following Converter classes:
public class MoneyJsonConverters {
public static class FromString extends StdConverter<String, Money> {
#Override
public Money convert(String value) {
return Money.from(value);
}
}
public static class ToString extends StdConverter<Money, String> {
#Override
public String convert(Money value) {
return value.toString();
}
}
}
Then I annotated the Pojo with #JsonDeserialize #JsonSerialize accordingly:
public class MoneyTestPojo {
#JsonSerialize(converter = MoneyJsonConverters.ToString.class)
#JsonDeserialize(converter = MoneyJsonConverters.FromString.class)
private Money value;
//getter and setter ommited
}
I have a paginated endpoint that looks like this /api/clients?range=0-25.
I'd like the getClients() method in my ClientController to directly receive an instance of a custom Range object rather than having to validate a "0-25" String but I'm having trouble figuring this out.
#Getter
final class Range {
#Min(0)
private Integer offset = 0;
#Min(1)
private Integer limit = 25;
}
#ResponseBody
#GetMapping(params = { "range" })
public ResponseEntity<?> getAllClients(#RequestParam(value = "range", required = false) QueryRange queryRange, final HttpServletResponse response) {
...
}
I'm not sure how to instruct the Controller to correctly deserialize the "0-25" string into the Range...
You can use a Converter<S, T>, as shown below:
#Component
public class RangeConverter implements Converter<String, Range> {
#Override
public Range convert(String source) {
String[] values = source.split("-");
return new Range(Integer.valueOf(values[0]), Integer.valueOf(values[1]));
}
}
You also could handle invalid values according to your needs. If you use the above converter as is, the attempt to convert an invalid value such as 1-x will result in a ConversionFailedException.
You can also do the following it seems :
public class QueryRangeEditor extends PropertyEditorSupport {
private static final Pattern PATTERN = Pattern.compile("^([1-9]\\d*|0)-([1-9]\\d*|0)$");
#Override
public void setAsText(String text) throws IllegalArgumentException {
final QueryRange range = new QueryRange();
Matcher matcher = PATTERN.matcher(text);
if (matcher.find()) {
range.setOffset(Integer.valueOf(matcher.group(1)));
range.setLimit(Integer.valueOf(matcher.group(2)));
} else {
throw new IllegalArgumentException("OI"); // todo - replace
}
setValue(range);
}
}
#InitBinder
public void initBinder(WebDataBinder binder) {
binder.registerCustomEditor(QueryRange.class, new QueryRangeEditor());
}
But #cassiomolin's looks cleaner...
I have a JAX-RS service that returns a Map<Artifact, String> and I have registered a
public class ArtifactAdapter implements JsonbAdapter<Artifact, String>
which a see hit when deserializing the in-parameter but not when serializing the return value, instead the Artifact toString() is used. If I change the return type to a Artifact, the adapter is called. I was under the impression that the Map would be serialized with built-in ways and then the adapter would be called for the Artifact.
What would be the workaround? Register an Adapter for the whole Map?
I dumped the thread stack in my toString and it confirms my suspicions
at java.lang.Thread.dumpStack(Thread.java:1336)
Artifact.toString(Artifact.java:154)
at java.lang.String.valueOf(String.java:2994)
at org.eclipse.yasson.internal.serializer.MapSerializer.serializeInternal(MapSerializer.java:41)
at org.eclipse.yasson.internal.serializer.MapSerializer.serializeInternal(MapSerializer.java:30)
at org.eclipse.yasson.internal.serializer.AbstractContainerSerializer.serialize(AbstractContainerSerializer.java:63)
at org.eclipse.yasson.internal.Marshaller.serializeRoot(Marshaller.java:118)
at org.eclipse.yasson.internal.Marshaller.marshall(Marshaller.java:74)
at org.eclipse.yasson.internal.JsonBinding.toJson(JsonBinding.java:98)
is the serializer hell-bent on using toString at this point?
I tried
public class Person {
private String name;
public Person(String name) {
this.name = name;
}
public String getName() {
return name;
}
}
public class PersonAdapter implements JsonbAdapter{
#Override
public String adaptToJson(Person obj) throws Exception {
return obj.getName();
}
#Override
public Person adaptFromJson(String obj) throws Exception {
return new Person(obj);
}
}
public class Test {
public static void main(String[] args) {
Map<Person, Integer> data = new HashMap<>();
data.put(new Person("John"), 23);
JsonbConfig config = new JsonbConfig().withAdapters(new PersonAdapter());
Jsonb jsonb = JsonbBuilder.create(config);
System.out.println(jsonb.toJson(data, new HashMap<Person, Integer>() {
}.getClass().getGenericSuperclass()));
}
}
but still ended up with the toString() of Person
Thanks in advance,
Nik
https://github.com/eclipse-ee4j/yasson/issues/110 (in my case since that's the default provider for WildFly)
I try to config cqrs and event sourcing with axon.
SeatReseveCreateCommand is work properly. but SeatReserveUpadateCommand is not work correct.
this is my SeatReserve aggregate
#Aggregate
public class SeatReserve {
#AggregateIdentifier
private String id;
private String seatid;
private Date date;
#SuppressWarnings("unused")
private SeatReserve() {
}
#CommandHandler
public SeatReserve(SeatReseveCreateCommand seatReseveCreateCommand) {
apply(new SeatReseveCreateEvent(seatReseveCreateCommand.getMyid(), seatReseveCreateCommand.getSeatId(),
seatReseveCreateCommand.getDate()));
}
#CommandHandler
public SeatReserve(SeatReserveUpadateCommand upadateCommand) {
apply(new SeatReserveUpadateEvent(id, upadateCommand.getSeatId()));
}
#EventSourcingHandler
public void on(SeatReseveCreateEvent seatReseveCreateEvent) {
this.id = seatReseveCreateEvent.getId();
this.seatid = seatReseveCreateEvent.getSeatId();
this.date = seatReseveCreateEvent.getDate();
}
#EventSourcingHandler
public void on(SeatReserveChangeEvent upadateEvent) {
seatid = upadateEvent.getSeatId();
}
}
this is my controller
#RestController
public class TestController {
private final CommandGateway commandGateway;
public TestController(CommandGateway commandGateway) {
this.commandGateway=commandGateway;
}
#PostMapping
public String fileComplaint(#RequestBody Map<String, String> request) {
String id = UUID.randomUUID().toString();
SeatReseveCreateCommand command=new SeatReseveCreateCommand(id,request.get("seatid"),new Date(request.get("date")));
commandGateway.send(command);
return id;
}
#PatchMapping
public String fileComplaintUpdate(#RequestBody Map<String, String> request) {
SeatReserveUpadateCommand command= new SeatReserveUpadateCommand(request.get("id"),request.get("seatid"));
commandGateway.send(command);
return request.get("id");
}
}
I try to send request using postman
this is my create request
this is my update request
update make this error
2018-01-03 10:44:53.608 WARN 11138 --- [nio-8085-exec-1] o.a.c.gateway.DefaultCommandGateway : Command 'com.thamira.research.api.bankaccount.SeatReserveUpadateCommand' resulted in org.axonframework.eventsourcing.IncompatibleAggregateException(Aggregate identifier must be non-null after applying an event. Make sure the aggregate identifier is initialized at the latest when handling the creation event.)
how can I solve this.
The problem is that your update command is defined as a constructor. The command should go to the already existing aggregate instance.
Changing the command handler to:
#CommandHandler
public void handle(SeatReserveUpadateCommand upadateCommand) {...}
should fix the issue.
I need to create an unmodifiable map generated from data obtained by querying a database. How, or can I, or is there a better way to do this using spring annotations?
I ran into a problem when creating a singleton for my Regions class and then trying to #Autowire in a RegionService to grab the object from the DAO. The problem is that spring can't instantiate the RegionService because it needs to instantiate the static singleton class Regions which needs to get data from the database as shown below in the constructor.
Please see me classes below (I've removed multiple unneeded methods that don't pertain to this question):
public final class Region {
private static final String DEFAULT_SEPERATOR = "-";
private final Integer key;
private final String description;
public Region(Integer pKey, String pDescription) {
this.key = pKey;
this.description = pDescription;
}
public Integer getKey() {
return this.key;
}
public String getValue() {
return this.description;
}
}
Here is my singleton:
public final class Regions {
private static Regions regionsInstance = null;
#Autowired
private RegionService regionService;
static Map<Integer, Region> regions;
private Regions() {
final Map<Integer, Region> tempRegions = new HashMap<Integer, Region>();
for (final Region region : this.regionService.retrieveAll()) {
tempRegions.put(region.getKey(), region);
}
regions = Collections.unmodifiableMap(tempRegions);
}
public static synchronized Regions getRegionsInstance() {
if (regionsInstance == null) {
regionsInstance = new Regions();
}
return regionsInstance;
}
public Region getRegion(final Integer pKey) {
return regions.get(pKey);
}
public List<Region> getRegions() {
return (List<Region>) regions.values();
}
}
My DAO and Service are just interfaces, no need to post those, here are my Impls:
#Service
public class RegionServiceImpl implements RegionService {
#Autowired
private RegionDAO regionDao;
#Override
public List<Region> retrieveAll() {
return this.regionDao.retrieveAll();
}
}
My DAOImpl (tested and works, just posting to give you the full picture):
#Repository
public class RegionDAOImpl implements RegionDAO {
private static final String SQL_RETRIEVE_REGIONS = "some random SQL";
#Autowired
private JdbcTemplate jdbcTemplate;
#Override
public List<Region> retrieveAll() {
try {
return this.jdbcTemplate.query(SQL_RETRIEVE_REGIONS, new ResultSetExtractor<List<Region>>() {
#Override
public List<Region> extractData(ResultSet rs) throws SQLException, DataAccessException {
return RegionDAOImpl.this.mapRegionData(rs);
}
});
} catch (final DataAccessException dae) {
throw new DaoException("Could not retrieve regionList from database. " + dae);
}
}
protected final List<Region> mapRegionData(ResultSet rs) throws SQLException {
final List<Region> regionList = new ArrayList<Region>();
while (rs.next()) {
regionList.add(new Region(rs.getInt("REGION_CD"), rs.getString("REGION_TXT")));
}
return Collections.unmodifiableList(regionList);
}
}
Then I run my test(I took out unneeded crap):
#..annotated with things you don't need to know
public class RetrieveRegionsTest {
#Autowired
private Regions r;
#Test
public void getAndLogRegion() {
final List<Region> regionDescriptions = new ArrayList<Region>(this.r.getRegions());
for (final Region region : regionDescriptions) {
LOGGER.info(region.getValue());
}
}
Yes my configuration and classpaths are set up properly. I can get this to work other ways, just not by accessing the Regions singleton which is what I want. Now I know I could take off the #Autowired on the RegionService in my Regions singleton and just create a new instance of RegionService, but that would defeat the purpose of springs #Autowired feature.
Any thoughts, ideas, comments?