net.talvi.puffinplot

Class RecentFileList

java.lang.Object

net.talvi.puffinplot.RecentFileList

public class RecentFileList
extends java.lang.Object

RecentFileList manages a list of file-sets. It is intended to be used to manage a collection of recently used files for convenient re-opening by a user. Note that each item in the list can comprise multiple files. The length of the list is currently hard-wired to 8, though this would be trivial to change if necessary.

RecentFileList can load and store data to a backing store which maps Strings to Strings; in normal use in the PuffinPlot desktop application, a Preferences object fulfils this role. The constructor and save method take functional interfaces as arguments, so any object providing put, get, and remove methods for a String-to-String map can be used as a store. RecentFileList prefixes its keys with the string recentFileX, where X is a non-negative integer less than the maximum number of file-sets. Note that RecentFileList does not synchronize with the store, except on instantiation (when it is initialized from the supplied getter) and on a call to save (when it writes to the store using the supplied remover and putter).

Constructor Summary

Constructors

Constructor and Description
RecentFileList(java.util.function.UnaryOperator<java.lang.String> getter) Creates a new file list, reading data (if any) using the supplied getter.

Method Summary

Modifier and Type	Method and Description
void	add(java.util.List<java.io.File> files) Adds a new file-set to the top of the list.
java.util.List<java.io.File>	getFilesAndReorder(int index) Returns a specified file-set and moves it to the top of the list.
java.util.List<java.lang.String>	getFilesetLongNames() Gets a list containing a long name for each fileset, intended for use in the tooltips of the recent files menu.
java.lang.String[]	getFilesetNames() Gets a list containing the names of the file-sets in the file list.
void	save(java.util.function.Consumer<java.lang.String> remover, java.util.function.BiConsumer<java.lang.String,java.lang.String> putter) Stores the recent file list using the supplied remover and putter functions.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RecentFileList

public RecentFileList(java.util.function.UnaryOperator<java.lang.String> getter)

Creates a new file list, reading data (if any) using the supplied getter. The getter must return null for a non-existent key. If any of the recentFile0 (and so on) keys are absent, no error is raised, and the corresponding slots in the file list are left empty.

Parameters:

getter - a function which takes a key and returns a value from a backing store

Method Detail

save

public void save(java.util.function.Consumer<java.lang.String> remover,
                 java.util.function.BiConsumer<java.lang.String,java.lang.String> putter)

Stores the recent file list using the supplied remover and putter functions.

Parameters:

remover - a function which takes a key and removes the corresponding key-value pair from a backing store. If the key is absent, it should do nothing.

putter - a function which stores a key-value pair, taking a key as the first argument and a value as the second argument. It will not be called with a null key or with a null value.

getFilesetNames

public java.lang.String[] getFilesetNames()

Gets a list containing the names of the file-sets in the file list. The names are expected to be displayed to the user. If a file-set contains only one file, its leafname is used. If it contains more than one file, the leafname of the first file is used, followed by ‘etc.’. Each name is prefixed by an index number starting from 1. This is intended to be used as a menu mnemonic.

Returns:

the list of file-set names from this recent files list

getFilesetLongNames

public java.util.List<java.lang.String> getFilesetLongNames()

Gets a list containing a long name for each fileset, intended for use in the tooltips of the recent files menu. The long name is the full pathname of the file (or the first file if there are multiple files in the set), with the leftmost part truncated if necessary to stay within a reasonable length.

Returns:

the list of long names for this recent files list

getFilesAndReorder

public java.util.List<java.io.File> getFilesAndReorder(int index)

Returns a specified file-set and moves it to the top of the list. This method is intended to be called when a user selects a recently used file. It returns the file at a specified index within the list, and (since this file is now the most recently used) moves it to the top of the list.

Parameters:

index - the zero-based index of a file-set within the list

Returns:

the requested file-set

add

public void add(java.util.List<java.io.File> files)

Adds a new file-set to the top of the list. If the list is already at its maximum length, the last item will be removed to make room.

Parameters:

files - the files to be added (as a single file-set) to the list