Cannot work with Jackson

Question

I am wondering why there is not a determined way to work with Jackson. I just want to parse JSON string:

ObjectMapper mapper = new ObjectMapper();
Customer[] myObjects = mapper.readValue(file, Customer[].class);

But I really confused what should I import to do that. According to this link, I tried to import mapper-asl.jar. But I get this compile error:

The type org.codehaus.jackson.JsonParser cannot be resolved. It is indirectly referenced from required .class files

Then I try to import jackson-core-2.4.2 and jackson-databind-2.4.2. So there was no compile error but I got this runtime exception instead (in mapper definition line):

java.lang.NoClassDefFoundError: com.fasterxml.jackson.annotation.JsonAutoDetect

Guide me please what should I import to work with Jackson. Thanks

Answer 1

use these dependencies jackson-databind
jackson-annotations
jackson-core

public class JsonTest {
    public static void main(String[] args) throws JsonProcessingException {
    ObjectMapper mapper=new ObjectMapper();
    Map<String,String> dt=new Hashtable();
    dt.put("1", "welcome");
    dt.put("2", "bye");
    String jsonString = mapper.writeValueAsString(dt)
    System.out.println(jsonString);
    }    
}

Answer 2

Looks like mixed up references.

You might be using a library that uses an old version of Jackson itself (i.e. the org.codehaus package)...

I usually just reference Jackson through Maven.

Something like:

<dependencies>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>LATEST</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>LATEST</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>LATEST</version>
    </dependency>
</dependencies>