Class MergeCombiner


  • public class MergeCombiner
    extends NodeCombiner

    A specialized implementation of the NodeCombiner interface that performs a merge from two passed in node hierarchies.

    This combiner performs the merge using a few rules:

    1. Nodes can be merged when attributes that appear in both have the same value.
    2. Only a single node in the second file is considered a match to the node in the first file.
    3. Attributes in nodes that match are merged.
    4. Nodes in both files that do not match are added to the result.

    Since:
    1.7
    Version:
    $Id: MergeCombiner.java 1301991 2012-03-17 20:18:02Z sebb $
    Author:
    Commons Configuration team
    • Constructor Detail

      • MergeCombiner

        public MergeCombiner()
    • Method Detail

      • addAttributes

        protected void addAttributes​(ViewNode result,
                                     ConfigurationNode node1,
                                     ConfigurationNode node2)
        Handles the attributes during a combination process. First all attributes of the first node will be added to the result. Then all attributes of the second node, which are not contained in the first node, will also be added.
        Parameters:
        result - the resulting node
        node1 - the first node
        node2 - the second node
      • canCombine

        protected ConfigurationNode canCombine​(ConfigurationNode node1,
                                               ConfigurationNode node2,
                                               ConfigurationNode child,
                                               java.util.List<ConfigurationNode> children2)
        Tests if the first node can be combined with the second node. A node can only be combined if its attributes are all present in the second node and they all have the same value.
        Parameters:
        node1 - the first node
        node2 - the second node
        child - the child node (of the first node)
        Returns:
        a child of the second node, with which a combination is possible