Scale of deserialized BigDecimal are not always the same

Hi,

When I use the annotation @JsonUnwrapped to materialize a component bean, the scale of the BigDecimal deserialized is different. I’ve written a test case below to reproduce the issue. Is there a way to control the scale of BigDecimal? Do I have to configure a custom deserializer?

(Test case reproduced with Jacskon 2.4.0 and 1.9.13 on Java 6)

Thanks,

Benoit

import com.fasterxml.jackson.annotation.JsonUnwrapped;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.junit.Assert;
import org.junit.Test;

import java.math.BigDecimal;

public class BigDecimalScaleTest {

    private String json = "{" +
            "  \"name\": \"Ben\"," +
            "  \"first\": 12.00," +
            "  \"second\": 14.00" +
            "}";

    private ObjectMapper objectMapper = new ObjectMapper();

    @Test
    public void testScale() throws Exception {

        MyDomain myDomain = objectMapper.readValue(json, MyDomain.class);

        MyFlatDomain myFlatDomain = objectMapper.readValue(json, MyFlatDomain.class);

        Assert.assertEquals(myDomain.getName(), myFlatDomain.getName());
        Assert.assertEquals(myDomain.getFirst(), myFlatDomain.getFirst()); // 12.00 = 12.00
        Assert.assertEquals(myDomain.getInnerDomain().getSecond(), myFlatDomain.getSecond());
         // 14.0 != 14.00
    }

    private static class MyDomain {
        private String name;
        private BigDecimal first;
        @JsonUnwrapped
        private MyInnerDomain innerDomain;

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public BigDecimal getFirst() {
            return first;
        }

        public void setFirst(BigDecimal first) {
            this.first = first;
        }

        public MyInnerDomain getInnerDomain() {
            return innerDomain;
        }

        public void setInnerDomain(MyInnerDomain innerDomain) {
            this.innerDomain = innerDomain;
        }
    }

    private static class MyInnerDomain {
        private BigDecimal second;

        public BigDecimal getSecond() {
            return second;
        }

        public void setSecond(BigDecimal second) {
            this.second = second;
        }
    }

    private static class MyFlatDomain {
        private String name;
        private BigDecimal first;
        private BigDecimal second;

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public BigDecimal getFirst() {
            return first;
        }

        public void setFirst(BigDecimal first) {
            this.first = first;
        }

        public BigDecimal getSecond() {
            return second;
        }

        public void setSecond(BigDecimal second) {
            this.second = second;
        }
    }

}

[azzoti]

Reproduced with jackson 2.5.1 Workaround possible with simple Deserializer:

public class MoneyDeserializer extends JsonDeserializer<BigDecimal> {

    private NumberDeserializers.BigDecimalDeserializer delegate = NumberDeserializers.BigDecimalDeserializer.instance;

    @Override
    public BigDecimal deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException {
        BigDecimal bd = delegate.deserialize(jp, ctxt);
        bd = bd.setScale(2, RoundingMode.HALF_UP);
        return bd;
    }    
}

Then us the deserializer like this to make the test pass

private static class MyInnerDomain {
    @JsonDeserialize(using=MoneyDeserializer.class)
    private BigDecimal second;

[cowtowncoder]

@mjustin Please file a new issue (with possible ref to this as background); I do not usually re-open closed issues as that complicates release notes significantly.