以下测试正常:

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 = "{ 
" +
            "  "timestamp" : "2014-08-20T11:51:31.233Z" 
" +
            "}";

    @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 配置:

<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>