Merging Two JSON Documents Using Jackson

Question

Is it possible to merge two JSON documents with the Jackson JSON library? I am basically using the Jackson mapper with simple Java Maps.

I\'ve tried to search in Goo

Answer 1

Below is an implementation in Scala. The source and target node are mostly commutative except when a branch exists in both source and target.

  def mergeYamlObjects(source: ObjectNode, target: ObjectNode, overwrite: Boolean = true): ObjectNode = {
    if (target == null)
      source
    else if (source == null)
      target
    else {
      val result = source.deepCopy
      val fieldlist = source.fieldNames.asScala.toList ++ target.fieldNames.asScala.toList
      for (item <- fieldlist) {
        if (!(source has item)) {
          result put(item, target get item)
        } else {
          if ((source get item).isValueNode) {
            if (target has item)
              if (overwrite)
                result.put(item, target get item)
          } else {
            result.put(item, mergeYamlObjects(source.get(item).asInstanceOf[ObjectNode],
              target.get(item).asInstanceOf[ObjectNode], overwrite = overwrite))
          }
        }
      }
      result
    }
  }