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 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.

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