I've been bashing my head with this proof of concept for a while. I want to consume a REST endpoint that returns JSON payload with an ISO8601 UTC timestamp:
{ ...
"timestamp" : "2014-08-20T11:51:31.233Z"
}
and I want to consume it using a command line Java client written as a Jersey 2 client with Jackson/Spring Boot. The marshalling POJO is defined as follows:
@JsonIgnoreProperties(ignoreUnknown = true)
@JsonInclude(Include.NON_NULL)
public class GreetingResource
{
@JsonProperty("timestamp")
private DateTime date;
...
}
After following recommendations shown in:
https://jersey.java.net/documentation/latest/user-guide.html#json.jackson
and using the following Gradle dependencies:
dependencies {
compile("org.springframework.boot:spring-boot-starter")
compile("org.springframework.boot:spring-boot-starter-logging")
compile("joda-time:joda-time")
compile("com.fasterxml.jackson.core:jackson-core")
compile("com.fasterxml.jackson.core:jackson-annotations")
compile("com.fasterxml.jackson.core:jackson-databind")
compile("com.fasterxml.jackson.datatype:jackson-datatype-joda")
compile("com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:2.3.3")
compile("org.apache.commons:commons-lang3:3.3.2")
compile("org.glassfish.jersey.core:jersey-client:2.2")
compile("org.glassfish.jersey.media:jersey-media-json-jackson:2.2")
testCompile("org.springframework.boot:spring-boot-starter-test")
}
I always get this error:
Exception in thread "main" javax.ws.rs.ProcessingException: Error reading entity from input stream.
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:849)
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:768)
at org.glassfish.jersey.client.InboundJaxrsResponse.readEntity(InboundJaxrsResponse.java:96)
at org.glassfish.jersey.client.ScopedJaxrsResponse.access$001(ScopedJaxrsResponse.java:56)
at org.glassfish.jersey.client.ScopedJaxrsResponse$1.call(ScopedJaxrsResponse.java:77)
at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
at org.glassfish.jersey.internal.Errors.process(Errors.java:228)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:397)
at org.glassfish.jersey.client.ScopedJaxrsResponse.readEntity(ScopedJaxrsResponse.java:74)
at client.GreetingClient.processResponse(GreetingClient.java:62)
at client.GreetingClient.performGet(GreetingClient.java:53)
at client.GreetingService.internalLoadGreeting(GreetingService.java:44)
at client.GreetingService.LoadGreeting(GreetingService.java:27)
at client.Application.main(Application.java:25)
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Can not instantiate value of type [simple type, class org.joda.time.DateTime] from String value ('2014-08-20T12:19:36.358Z'); no single-String constructor/factory method (through reference chain: client.GreetingResource["timestamp"])
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator._createFromStringFallbacks(StdValueInstantiator.java:428)
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromString(StdValueInstantiator.java:299)
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromString(BeanDeserializerBase.java:1150)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:139)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:126)
at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:525)
at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:99)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:242)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:118)
at com.fasterxml.jackson.databind.ObjectReader._bind(ObjectReader.java:1233)
at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:677)
at com.fasterxml.jackson.jaxrs.base.ProviderBase.readFrom(ProviderBase.java:777)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:188)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:134)
I have given up. What am I doing wrong?
The client is configured as follows:
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Invocation.Builder;
import javax.ws.rs.client.WebTarget;
import org.glassfish.jersey.client.ClientConfig;
...
@Component
public class GreetingClient
{
private final WebTarget serviceWebTarget;
{
ClientConfig config = new ClientConfig();
config.register(MyObjectMapperProvider.class);
config.register(JacksonFeatures.class);
Client client = ClientBuilder.newClient(config);
this.serviceWebTarget = client.target("http://myserver:8080");
}
...
}
The registered provider is defined as (in the same package as the client):
@Provider
public class MyObjectMapperProvider implements ContextResolver<ObjectMapper>
{
private final static DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
@Override
public ObjectMapper getContext(Class<?> type)
{
final ObjectMapper result = new JodaMapper();
result.setDateFormat(dateFormat);
return result;
}
}
I have tried with/without registering the provider and also annotating the field to use DateTimeDeserializer (through @JsonDeserialize) - only to get an error because "there is no default no-arg constructor available".
If I use standard java.util.Date instead with
@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")
it works like a breeze.
Any clues? Thanks for your help.
Below test works OK:
import java.io.IOException;
import org.joda.time.DateTime;
import org.junit.Test;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.datatype.joda.JodaModule;
public class JacksonTest {
private static final String json = "{ \n" +
" \"timestamp\" : \"2014-08-20T11:51:31.233Z\" \n" +
"}";
@Test
public void test() throws IOException {
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JodaModule());
System.out.println(mapper.readValue(json, GreetingResource.class));
}
}
@JsonIgnoreProperties(ignoreUnknown = true)
@JsonInclude(Include.NON_NULL)
class GreetingResource {
@JsonProperty("timestamp")
private DateTime date;
public DateTime getDate() {
return date;
}
public void setDate(DateTime date) {
this.date = date;
}
@Override
public String toString() {
return "GreetingResource{" +
"date=" + date +
'}';
}
}
Maven configuration:
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.4.1.1</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.4.1.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.4.1</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-joda</artifactId>
<version>2.4.0</version>
</dependency>
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>2.4</version>
</dependency>
For anyone else having issues, none of the other answers were really fully complete so its this
WebTarget target = ClientBuilder.newClient().target(host);
JacksonJaxbJsonProvider provider = new JacksonJaxbJsonProvider();
provider.setMapper(new JodaMapper());
target.register(provider);
I have come across the same problem. What you have to do is to register custom ObjectMapper in Jersey:
@Component
public class JerseyConfig extends ResourceConfig {
public JerseyConfig() {
JacksonJaxbJsonProvider provider = new JacksonJaxbJsonProvider();
provider.setMapper(new JodaMapper());
register(provider);
packages("endpoints.package.names");
}
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With