module HexaPDF::Utils::SortedTreeNode

Provides the convenience methods that are used for name trees and number trees.

The provided methods require two methods defined in the including class so that they work correctly:

leaf_node_container_name

Defines the dictionary entry name that contains the leaf node entries.

For example, for name trees this would be :Names.

key_type

Defines the class that is used for the keys in the tree.

The class defined this way is used for making sure that only valid keys are used.

For example, for name trees this would be String.

Note: Like with HexaPDF::Dictionary, the keys are assumed to always be direct objects!

See: HexaPDF::NameTreeNode, HexaPDF::NumberTreeNode

Public Instance Methods

add_entry(key, data, overwrite: true) → true or false

Adds a new tree entry (key-data pair) to the sorted tree and returns true if it was successfully added.

If the option overwrite is true, an existing entry is overwritten. Otherwise an error is raised.

This method has to be invoked on the root node of the tree!

delete_entry(key)

Deletes the entry specified by the key from the tree and returns the data. If the tree doesn’t contain the key, nil is returned.

This method has to be invoked on the root node of the tree!

each_entry {|key, data| block } → node
each_entry → Enumerator

Calls the given block once for each entry (key-data pair) of the sorted tree.

find_entry(key)

Finds and returns the associated entry for the key, or returns nil if no such key is found.

must_be_indirect?()

Tree nodes must always be indirect.

Note: There is no requirement that the root node of a tree must be indirect. However, making it indirect simplifies the implementation and is not against the spec.