what is wrong in this code? it is throwing the null error

Question

package com.vaadin.ui.view;

public class AddConsumerView extends FormLayout{

private ConsumerUI consumerUI;

@Autowired
private ConsumerServiceInterface consumerServiceInterface;

//horizontal layout for the id's
private HorizontalLayout consumerIDLayout = new HorizontalLayout();
private TextField consumer_id = new TextField("Consumer Id");
private TextField household_id = new TextField("Household Id");
private TextField legal_hold = new TextField("Legal Hold");
private TextField deceased_fg = new TextField("Deceased");
private DateTimeField deceased_dt = new DateTimeField("Deceased DateTime");


//Horizontal layout for the INS
private HorizontalLayout consumerINSLayout = new HorizontalLayout();
private TextField ins_pqid = new TextField("Ins PQID");
private TextField ins_rid = new TextField("Ins RID");
private TextField ins_efid = new TextField("Ins EFID");
private DateTimeField ins_tmstmp = new DateTimeField("Ins Date time");

// Horizontal layout for the UPD
private HorizontalLayout consumerUPDLayout = new HorizontalLayout();
private TextField upd_pqid = new TextField("Upd PQID");
private TextField upd_rid= new TextField("Upd RID");
private TextField upd_efid = new TextField("Upd EFID");
private DateTimeField upd_tmstmp = new DateTimeField("Upd Date time");
private Consumer consumerData = new Consumer();

//Buttons
private Button saveConsumerButton =  new Button("save"); 

//binding the data to the field
private Binder<Consumer> consumerBinder = new Binder<>(Consumer.class);





public AddConsumerView(ConsumerUI consumerUI) {
    this.consumerUI = consumerUI;
    consumerIDLayout.addComponents(consumer_id, household_id, legal_hold, deceased_dt,deceased_fg);
    consumerINSLayout.addComponents(ins_pqid, ins_rid, ins_efid, ins_tmstmp);
    consumerUPDLayout.addComponents(upd_pqid,upd_rid, upd_efid, upd_tmstmp);
    VerticalLayout vertical = new VerticalLayout();
    vertical.addComponents(consumerIDLayout, consumerINSLayout, 
    consumerUPDLayout,saveConsumerButton);
    //addComponent(vertical);
    bindFields();
    consumerBinder.setBean(new Consumer());
    saveConsumerButton.setStyleName("primary");
    saveConsumerButton.addClickListener(e->saveConsumer());
    addComponents(vertical);
}


public void saveConsumer() {


    //consumerBinder.bindInstanceFields(this);

    System.out.println(consumerBinder.getBean().toString());
    consumerServiceInterface.addConsumer(consumerBinder.getBean());
}

public void bindFields() {

consumerBinder.forField(consumer_id)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getConsumer_id,Consumer::setConsumer_id);

consumerBinder.forField(legal_hold)
    .bind(Consumer::getLegal_hold, Consumer::setLegal_hold);

consumerBinder.forField(deceased_fg)
    .bind(Consumer::getDeceased_fg, Consumer::setDeceased_fg);

consumerBinder.forField(household_id)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getHousehold_id,Consumer::setHousehold_id);

consumerBinder.forField(ins_efid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getIns_efid,Consumer::setIns_efid);

consumerBinder.forField(ins_pqid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getIns_pqid,Consumer::setIns_pqid);

consumerBinder.forField(ins_rid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getIns_rid,Consumer::setIns_rid);

consumerBinder.forField(upd_efid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getUpd_efid,Consumer::setUpd_efid);

consumerBinder.forField(upd_pqid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getUpd_pqid,Consumer::setUpd_pqid);

consumerBinder.forField(upd_rid)
    .withConverter(new StringToLongConverter("Must be a number"))
    .bind(Consumer::getUpd_rid,Consumer::setUpd_rid);

consumerBinder.forField(upd_tmstmp)
    .withConverter(new StringTimestampConvertor())
    .bind(Consumer::getUpd_tmstmp, Consumer::setUpd_tmstmp);

consumerBinder.forField(ins_tmstmp)
    .withConverter(new StringTimestampConvertor())
    .bind(Consumer::getIns_tmstmp, Consumer::setIns_tmstmp);

consumerBinder.forField(deceased_dt)
    .withConverter(new StringTimestampConvertor())
    .bind(Consumer::getDeceased_dt, Consumer::setDeceased_dt);

consumerBinder.forField(upd_tmstmp)
    .withConverter(new StringTimestampConvertor())
    .bind(Consumer::getUpd_tmstmp, Consumer::setUpd_tmstmp);


    }

}

StringTimestampConvertor Class

package com.vaadin.convertor;


    @SuppressWarnings("serial")
    public class StringTimestampConvertor implements Converter<LocalDateTime, Timestamp> {

    @SuppressWarnings("unchecked")

    public Result<Timestamp> convertToModel(LocalDateTime value, ValueContext context) {
        System.out.println("check"+value);
        Result<Timestamp> rs =  Result.ok(Timestamp.valueOf(value));
        return rs;
    }

    @Override
    public LocalDateTime convertToPresentation(Timestamp value, ValueContext context) {
        // TODO Auto-generated method stub
        return null;
    }

}

The sysout is working but the saveConsumer function is giving null error and also the stringtimestampconvertor is being run many times.

java.lang.NullPointerException: null at com.vaadin.ui.view.AddConsumerView.saveConsumer(AddConsumerView.java:82) ~[classes/:na] at com.vaadin.ui.view.AddConsumerView.lambda$0(AddConsumerView.java:71) ~[classes/:na] at com.vaadin.ui.view.AddConsumerView$$Lambda$1501/954546734.buttonClick(Unknown Source) ~[na:na] at sun.reflect.GeneratedMethodAccessor433.invoke(Unknown Source) ~[na:na] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_45] at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_45] at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:211) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:174) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.AbstractClientConnector.fireEvent(AbstractClientConnector.java:1029) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.ui.Button.fireClick(Button.java:370) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.ui.Button$1.click(Button.java:57) ~[vaadin-server-8.0.0.jar:8.0.0] at sun.reflect.GeneratedMethodAccessor432.invoke(Unknown Source) ~[na:na] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_45] at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_45] at com.vaadin.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:155) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:116) ~[vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.communication.ServerRpcHandler.handleInvocation(ServerRpcHandler.java:443) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:415) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:274) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:90) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1464) [vaadin-server-8.0.0.jar:8.0.0] at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:380) [vaadin-server-8.0.0.jar:8.0.0] at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-embed-websocket-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) [tomcat-embed-core-8.5.29.jar:8.5.29] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.29.jar:8.5.29] at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0_45] at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0_45] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.29.jar:8.5.29] at java.lang.Thread.run(Unknown Source) [na:1.8.0_45]

Everything is working fine except while submitting the form the saveConsumer function the sysout statement is working fine but the consumerServiceInterface.saveConsumer(conusmerBinder.getBean()) is throwing null error

Not that it would help, but why are you using what seems to be Vaadin 8.0.0? You might pick up some wrong deps in your build tool. — cfrick, Jan 06 '20 at 12:03

cfrick · Accepted Answer · 2020-01-06T12:16:44.113

Unless you create your form via Spring you won't get @Autowired to work. Never use @Autowired fields, always use constructor based injection and this sort of problem hits you way sooner.

Then you are forced to either

construct manually and pass the required objects in (what you can do higher up in the chain, where things take part in the Spring mechnisms (e.g. Vaadin Views))
or you are forced use the Spring mechanisms yourself (e.g. get a bean from the application context)

I suggest taking a look at the docs

anasmi · Answer 2 · 2020-01-06T10:41:39.587

Edit:

Could you verify that your instance of ConsumerServiceInterface is not null? You are not using a @Route on the view, so how you are using this view in an app? If it happens via constructor, then Spring is not autowiring a field. How does autowiring work in Spring

Based on your previous question here: How to enter a timestamp in Vaadin 8 I would assume that you are getting NPE at

Result<Timestamp> rs = Result.ok(Timestamp.valueOf(value));

Which is expected, if passed value is null JavaDocs: Timestamp valueOf. You should add a proper null check there and based on that proceed further

Also, why are you returning for any Timestamp a null LocalDateTime?

You should do instead something like this Datamodel Conversion:

class MyConverter implements Converter<String, Integer> {
  @Override
  public Result<Integer> convertToModel(String fieldValue, ValueContext context) {
    // Produces a converted value or an error
    try {
      // ok is a static helper method that creates a Result
      return Result.ok(Integer.valueOf(fieldValue));
    } catch (NumberFormatException e) {
      // error is a static helper method that creates a Result
      return Result.error("Please enter a number");
    }
  }

  @Override
  public String convertToPresentation(Integer integer, ValueContext context) {
    // Converting to the field type should always succeed,
    // so there is no support for returning an error Result.
    return String.valueOf(integer);
  }
}

`consumerServiceInterface` could you verify it's not null? How are you using (where are you adding)`AddConsumerView` ? I don't see a `@Route` annotation. Thus if you are using a `new AddConsumerView ()` this will not work as Spring is not opt-in — anasmi, Jan 06 '20 at 10:34
based on the given information, this is probably the problem (however i dont think vaadin 7/8 had the `@Route` annotation). @deepKumar you need to autowire the `ConsumerServiceInterface` in the View that is the initial navigation target, and pass the instance into the constructor of `AddConsumerView`. See [this answer](https://stackoverflow.com/a/59410169/3441504) for more detailed info — kscherrer, Jan 06 '20 at 10:41
anasmi yes the **consumerServiceInterface** is null. I am using veedin 8 and there is no @route in vaadin 8 — deep Kumar, Jan 07 '20 at 05:53
Then as @cfrick has wrote in his answer your should either construct your object via constructor or, otherwise, autowire the view as well. — anasmi, Jan 07 '20 at 06:08

what is wrong in this code? it is throwing the null error

2 Answers2