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

Interface Config.Key

All Superinterfaces:
Comparable<Config.Key>, Config.Key
Enclosing interface:
Config
public static interface Config.Key extends 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:

  • Method Summary

    Modifier and Type
    Method
    Description
    Config.Key
    child(Config.Key key)
    Create a child key to the current key.
    static Config.Key
    create(String key)
    Creates new instance of Key for specified key literal.
    static String
    escapeName(String name)
    Escape '~' to ~0 and '.' to ~1 in specified name.
    boolean
    isRoot()
    Returns true in case the key represents root config node, otherwise it returns false.
    String
    name()
    Returns the name of Config node.
    Config.Key
    parent()
    Returns instance of Key that represents key of parent config node.
    String
    toString()
    Returns formatted fully-qualified key.
    static String
    unescapeName(String escapedName)
    Unescape ~0 to '~' and ~1 to '.' in specified escaped name.

    Methods inherited from interface java.lang.Comparable

    compareTo

  • Method Details

    • 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.

      Specified by:
      parent in interface Config.Key
      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:

    • child

      Config.Key child(Config.Key key)
      Create a child key to the current key.
      Specified by:
      child in interface Config.Key
      Parameters:
      key - child key (relative to current key)
      Returns:
      a new resolved key

    • isRoot

      boolean isRoot()
      Returns true in case the key represents root config node, otherwise it returns false.
      Specified by:
      isRoot in interface Config.Key
      Returns:
      true in case the key represents root node, otherwise false.
      Throws:
      ConfigException - if not defined
      See Also:

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

    • toString

      String toString()
      Returns formatted fully-qualified key.
      Specified by:
      toString in interface Config.Key
      Overrides:
      toString in class Object
      Returns:
      formatted fully-qualified 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