Module io.helidon.config
Package io.helidon.config

Interface Config.Key

  • All Superinterfaces:
    Comparable<Config.Key>
    Enclosing interface:
    Config
    public static interface Config.Key
extends Comparable<Config.Key>
    Object represents fully-qualified key of config node.

    Fully-qualified key is list of key tokens separated by . (dot character). Depending on context the key token is evaluated one by one:

    • in Config.Type.OBJECT node the token represents a name of object member;
    • in Config.Type.LIST node the token represents an zero-based index of list element, an unsigned base-10 integer value, leading zeros are not allowed.

    The ABNF syntax of config key is: 

    
 config-key = *1( key-token *( "." key-token ) )
  key-token = *( unescaped / escaped )
  unescaped = %x00-2D / %x2F-7D / %x7F-10FFFF
            ; %x2E ('.') and %x7E ('~') are excluded from 'unescaped'
    escaped = "~" ( "0" / "1" )
            ; representing '~' and '.', respectively
    See Also:
    Config.key()

    • Method Detail

      • parent

        Config.Key parent()
        Returns instance of Key that represents key of parent config node.

        If the key represents root config node it throws an exception.

        Returns:
        key that represents key of parent config node.
        Throws:
        IllegalStateException - in case you attempt to call this method on a root node
        See Also:
        isRoot()

      • isRoot

        boolean isRoot()
        Returns true in case the key represents root config node, otherwise it returns false.
        Returns:
        true in case the key represents root node, otherwise false.
        See Also:
        parent()

      • name

        String name()
        Returns the name of Config node.

        The name of a node is the last token in fully-qualified key. Depending on context the name is evaluated one by one:

        • in Config.Type.OBJECT node the name represents a name of object member;
        • in Config.Type.LIST node the name represents an zero-based index of list element, an unsigned base-10 integer value, leading zeros are not allowed.
        Returns:
        name of config node
        See Also:
        Config.name()

      • toString

        String toString()
        Returns formatted fully-qualified key.
        Overrides:
        toString in class Object
        Returns:
        formatted fully-qualified key.

      • child

        Config.Key child​(Config.Key key)
        Create a child key to the current key.
        Parameters:
        key - child key (relative to current key)
        Returns:
        a new resolved key

      • create

        static Config.Key create​(String key)
        Creates new instance of Key for specified key literal.

        Empty literal means root node. Character dot ('.') has special meaning - it separates fully-qualified key by key tokens (node names).

        Parameters:
        key - formatted fully-qualified key.
        Returns:
        Key instance representing specified fully-qualified key.

      • escapeName

        static String escapeName​(String name)
        Escape '~' to ~0 and '.' to ~1 in specified name.
        Parameters:
        name - name to be escaped
        Returns:
        escaped name

      • unescapeName

        static String unescapeName​(String escapedName)
        Unescape ~0 to '~' and ~1 to '.' in specified escaped name.
        Parameters:
        escapedName - escaped name
        Returns:
        unescaped name