Module io.helidon.config

Package io.helidon.config.spi

Interface MergingStrategy

public interface MergingStrategy

An algorithm for combining multiple ConfigNode.ObjectNode root nodes into a single ConfigNode.ObjectNode root node.

See Also:

• default merging strategy

Method Summary

Modifier and Type	Method	Description
static MergingStrategy	fallback()	Returns an implementation of MergingStrategy in which nodes from a root earlier in the list have higher priority than nodes from a root later in the list.
ConfigNode.ObjectNode	merge(List<ConfigNode.ObjectNode> rootNodes)	Merges an ordered list of ConfigNode.ObjectNodes into a single instance.

Method Details

merge

ConfigNode.ObjectNode merge(List<ConfigNode.ObjectNode> rootNodes)

Merges an ordered list of ConfigNode.ObjectNodes into a single instance.

Typically nodes (object, list or value) from a root earlier in the list are considered to have a higher priority than nodes from a root that appears later in the list, but this is not required and is entirely up to each MergingStrategy implementation.

Parameters:

rootNodes - list of root nodes to combine

Returns:

ObjectNode root node resulting from the merge

fallback

static MergingStrategy fallback()

Returns an implementation of MergingStrategy in which nodes from a root earlier in the list have higher priority than nodes from a root later in the list.

The merged behavior is as if the resulting merged Config, when resolving a value of a key, consults the Config roots in the order they were passed to merge. As soon as it finds a Config tree containing a value for the key is it immediately returns that value, disregarding other later config roots.

Returns:

new instance of fallback merging strategy