typeMismatch.target spring boot batch rejected value [2020-09-18T00:00:00+02:00]

Question

I am trying to integrate data from CSV file with spring boot using a batch, I have a problem with the date field because it is constantly rejected regardless of the type used, here is my code:

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String service;
    private Timestamp time;

    @Override
    public IndProd process(final IndProd indProd) throws Exception {
        String service = indProd.getService();
        Timestamp time = indProd.getTime();
        Long nbAppels = indProd.getNbAppels();
        Integer tempsDeReponseMoyenMillisecondes = indProd.getTempsDeReponseMoyenMillisecondes();
        Long volume = indProd.getVolume();
        BigDecimal tempsDeReponseMoyenSecondes = indProd.getTempsDeReponseMoyenSecondes();
        IndProd transformedIndProd = new IndProd(service,time,nbAppels,tempsDeReponseMoyenMillisecondes,volume,tempsDeReponseMoyenSecondes);

        return transformedIndProd;
    }

here is the error returned:

Caused by: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors Field error in object 'target' on field 'time': rejected value [2020-09-18T00:00:00+02:00]; codes [typeMismatch.target.time,typeMismatch.time,typeMismatch.java.sql.Timestamp,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [target.time,time]; arguments []; default message [time]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'java.sql.Timestamp' for property 'time'; nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.lang.String' to required type 'java.sql.Timestamp' for property 'time': no matching editors or conversion strategy found] at org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper.mapFieldSet(BeanWrapperFieldSetMapper.java:201) ~[spring-batch-infrastructure-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.batch.item.file.mapping.DefaultLineMapper.mapLine(DefaultLineMapper.java:43) ~[spring-batch-infrastructure-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.batch.item.file.FlatFileItemReader.doRead(FlatFileItemReader.java:185) ~[spring-batch-infrastructure-4.2.4.RELEASE.jar:4.2.4.RELEASE] ... 56 common frames omitted

Thanks for your help

Answer 1

From the error, it clear that indProd.getTime() returns a String value which you are trying to assign to a Timestamp variable. Assuming indProd.getTime() returns a date-time string in the format, yyyy-MM-dd'T'HH:mm:ssXXX e.g. 2020-09-18T00:00:00+02:00 (as mentioned in the title of your question), you should replace

Timestamp time = indProd.getTime();

with

Timestamp time = new Timestamp(new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX").parse(indProd.getTime()).getTime());

Note: java.sql.Timestamp extends java.util.Date and the date-time API of java.util and their formatting API, SimpleDateFormat are outdated and error-prone. I suggest you should stop using them completely and switch to the modern date-time API.

Using the modern date-time API:

OffsetDateTime odt = OffsetDateTime.parse(indProd.getTime());
//...
IndProd transformedIndProd = new IndProd(service,odt,nbAppels,tempsDeReponseMoyenMillisecondes,volume,tempsDeReponseMoyenSecondes);

and declare the instance members as

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String service;
private OffsetDateTime odt;// Change the type to OffsetDateTime

Learn more about the modern date-time API at Trail: Date Time. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.

Answer 2

As the error said you are trying to assign a String value to an Instant variable. That mean indProd.getTime() is trying to be String.

One way to fix this is to retype to String back to instant, it is maybe not the best solution but is should work.

Timestamp time = Timestamp.from(ZonedDateTime.parse(indProd.getTime()).toInstant());

and in IndProd variable change time to String