Setting default values to null fields when mapping with Jackson

I am trying to map some JSON objects to Java objects with Jackson. Some of the fields in the JSON object are mandatory(which I can mark with @NotNull) and some are optional.

After the mapping with Jackson, all the fields that are not set in the JSON object will have a null value in Java. Is there a similar annotation to @NotNull that can tell Jackson to set a default value to a Java class member, in case it is null?

Edit: To make the question more clear here is some code example.

The Java object:

class JavaObject {
    @NotNull
    public String notNullMember;

    @DefaultValue("Value")
    public String optionalMember;
}

The JSON object can be either:

{
    "notNullMember" : "notNull"
}

or:

{
    "notNullMember" : "notNull",
    "optionalMember" : "optional"
}

The @DefaultValue annotations is just to show what I am asking. It's not a real annotation. If the JSON object is like in the first example I want the value of the optionalMember to be "Value" and not null. Is there an annotation that does such a thing?

There is no annotation to set default value.
You can set default value only on java class level:

public class JavaObject 
{
    public String notNullMember;

    public String optionalMember = "Value";
}

Only one proposed solution keeps the default-value when some-value:null was set explicitly (POJO readability is lost there and it's clumsy)

Here's how one can keep the default-value and never set it to null

@JsonProperty("some-value")
public String someValue = "default-value";

@JsonSetter("some-value")
public void setSomeValue(String s) {
    if (s != null) { 
        someValue = s; 
    }
}