info.aduna.gee.publication.util
Class WLZ7710

java.lang.Object
  info.aduna.gee.publication.util.WLZ7710

All Implemented Interfaces:

LocalNames

public class WLZ7710
extends Object
implements LocalNames

Implements the LZ7710-Compression algorithm specific to ZPad usage.

Field Summary

protected int	_match
protected int	_position
static int	WINDOW

Fields inherited from interface info.aduna.gee.publication.LocalNames

AM, APRIL, AUGUST, BUTTON_ADD, BUTTON_ASSOCIATES_MAY_NOT_EDIT, BUTTON_BACKUP, BUTTON_BOTTOM, BUTTON_CLEAR, BUTTON_CLEAR_CART, BUTTON_DELETE, BUTTON_DESCRIPTION, BUTTON_DOWN, BUTTON_EDIT, BUTTON_EDIT_CLABELS, BUTTON_EDIT_SUBSCRIPTION, BUTTON_EDIT_SUBSCRIPTIONS, BUTTON_ENTRY_FROM_CLIPBOARD, BUTTON_ENTRY_TO_CLIPBOARD, BUTTON_EXIT_EDIT_MODE, BUTTON_FAST_BACKWARD, BUTTON_FAST_FORWARD, BUTTON_FIND_FUTURE, BUTTON_FIND_PAST, BUTTON_INTERNALIZE_ENTRY, BUTTON_LINK, BUTTON_LINK_IN_FRAME, BUTTON_LOCK_ZPAD, BUTTON_MORE_TEXT, BUTTON_NEXTCONTENT, BUTTON_PERSONALIZE, BUTTON_PL0, BUTTON_PL1, BUTTON_PL2, BUTTON_PL3, BUTTON_PL4, BUTTON_PREVIOUSCONTENT, BUTTON_PROVIDE_ENTRY, BUTTON_RE_EXPORT, BUTTON_RE_MANUAL, BUTTON_REPEAT, BUTTON_REPEAT_TODAY, BUTTON_RESTORE, BUTTON_SEND_ORDER, BUTTON_SUGGESTED_DESTINATION, BUTTON_SUMMARY, BUTTON_SYNCHRONIZE, BUTTON_TIME, BUTTON_TODAY, BUTTON_TOMORROW, BUTTON_TOOLS, BUTTON_TOP, BUTTON_UNDO, BUTTON_UP, BUTTON_UPLOAD_IMAGE, BUTTON_YESTERDAY, CONFIRM_BACKUP_ERROR, CONFIRM_CHANGE_ALL_REPEATING, CONFIRM_CLABEL_DEFINITION_FORMAT, CONFIRM_COULD_NOT_SAVE, CONFIRM_DELETE_ALL_REPEATING, CONFIRM_DELETE_EXPIRED, CONFIRM_ERROR, CONFIRM_FILE_CHANGED, CONFIRM_FILE_CHANGED_TITLE, CONFIRM_FILE_REALLY_CHANGED, CONFIRM_FIND_CONTENT, CONFIRM_FIRST_SECTION, CONFIRM_HAS_THEMES_FRAME, CONFIRM_MIXED_TODAY, CONFIRM_NO_MORE_CONTENT, CONFIRM_NOT_A_ZPAD, CONFIRM_NOT_REMOVE_SECTION, CONFIRM_QUESTION, CONFIRM_READONLY_BROWSER, CONFIRM_SURE, CONFIRM_THIS_ZPAD, CONFIRM_TODAY_IS_AT_STARTUP, CONFIRM_TODAY_IS_AT_TRANSFER, CONFIRM_UNDO, DECEMBER, ENTRY_TYPE_APPLET, ENTRY_TYPE_HTML, ENTRY_TYPE_IMAGE, ENTRY_TYPE_OBJECT, ENTRY_TYPE_TEXT, ENTRY_TYPE_TMPLD, ERROR_CONFIG_LOAD, ERROR_DATABASE_LOAD, ERROR_IMAGE_LOAD, ERROR_RESOLVE_LOCATION, ERROR_ZPAD_LOAD, EXC_INVALID_PORT_NUMBER, EXC_NO_GZIP_SUPPORT, EXC_NO_HOSTNAME_SPECIFIED, EXC_UNKNOWN_COMPR, EXC_UNKNOWN_ENCODING, EXC_VELOCITY_NOT_SHOWN, FEBRUARY, FRIDAY, FROM, GETTING_BUTTONS, GETTING_CONTENT, HTML_EDIT_ENTRY, HTML_ENTRY_EXPIRED, HTML_ENTRY_NOT_YET_INSPIRED, HTML_ENTRY_WILL_EXPIRE, HTML_MOVE_ENTRY, HTML_ZPAD_GET_ENTRY, INVALID_USER_LOCATION, JANUARY, JULY, JUNE, LABEL_ACCEPT_BATCH, LABEL_ADD_TO_CART, LABEL_ALL_CLABELS, LABEL_ALLSUB_SECTIONS, LABEL_APPLET_CODE, LABEL_APPLET_CODEBASE, LABEL_AT_STARTUP, LABEL_AT_STARTUP_BRIEF, LABEL_BACKGROUND, LABEL_BATCH_IS_MULTIPLE, LABEL_BATCH_NEW_SECTION, LABEL_BLUE, LABEL_BOTTOMUP_SUBSCRIPTION, LABEL_CART_EMPTY, LABEL_CASE_SENSITIVE, LABEL_CHOOSE_SECTION, LABEL_CHOOSE_TMPL, LABEL_CLABEL_IMAGE, LABEL_CLABEL_OVER_IMAGE, LABEL_CLABEL_RULE, LABEL_CLABELS, LABEL_CLABELS_SELECTED, LABEL_COUNT, LABEL_COVER_SECTIONS, LABEL_COVER_SPECIFIC_BUTTONS, LABEL_COVER_SPECIFIC_ENTRY_BUTTONS, LABEL_COVER_USES_HIERMENU, LABEL_COVER_USES_HIERMENU_ALL_OPTION, LABEL_COVER_USES_INPAGE, LABEL_COVER_USES_JOUST, LABEL_CURRENT_SECTIONS, LABEL_DAILY, LABEL_DATE, LABEL_DAYOFWEEK, LABEL_DESCR, LABEL_DESCRIPTION, LABEL_DESTINATION, LABEL_DONT_INHERIT, LABEL_EDIT_BATCH, LABEL_EMBED_SOURCE, LABEL_ENTRY_HTML, LABEL_ENTRY_IS_TMPL, LABEL_FOREGROUND, LABEL_GREEN, LABEL_HEIGHT, LABEL_HTML_STYLE, LABEL_ID, LABEL_IMAGE_LOCATION, LABEL_IMPORT_CLASSNAME, LABEL_IMPORT_SERVERNAME, LABEL_INHERIT_CLABELS, LABEL_INHERIT_PRIVACY_GROUPS, LABEL_INLINE_DESCRIPTION, LABEL_INPAGE_ALT_TEMPLATE_ID, LABEL_INPAGE_ALT_TEMPLATE_SOURCE, LABEL_INPAGE_SUB_TEMPLATE_ID, LABEL_INPAGE_SUB_TEMPLATE_SOURCE, LABEL_INPAGE_SUBSUB_TEMPLATE_ID, LABEL_INPAGE_SUBSUB_TEMPLATE_SOURCE, LABEL_INPAGE_TEMPLATE_ID, LABEL_INPAGE_TEMPLATE_SOURCE, LABEL_LOADED_FRAMES, LABEL_LOADED_TEMPLATES, LABEL_MONTH, LABEL_MONTHLY, LABEL_MOUNTPOINT, LABEL_MULTISUB_SECTIONS, LABEL_NEVER_EXPIRES, LABEL_NEVER_INSPIRES, LABEL_NEW_CLABEL, LABEL_NEW_FRAME, LABEL_NEW_PL_MEMBER, LABEL_NEW_SECTION, LABEL_NEW_SUBSCRIPTION, LABEL_NEW_TEMPLATE, LABEL_NEW_ZPAD_NAME, LABEL_NO_COLOR, LABEL_NO_ENTRY_SPECIFIC_PROPERTIES, LABEL_NO_FRAME, LABEL_NO_TEMPLATE_PREFERENCE, LABEL_NOT_AT_THIS_PL, LABEL_NOT_IN_CLIENTMODE, LABEL_OBJECT_LOCATION, LABEL_OCCURRING_SUBSCRIPTION, LABEL_OPTIONS, LABEL_ORDER_PRICE, LABEL_OWN_CONTENTS_ONLY, LABEL_OWN_SECTIONS, LABEL_OWNER_VERSION, LABEL_PASSWORD, LABEL_PASSWORD_ERROR, LABEL_PL_MEMBERS, LABEL_PLUS_ASSOCIATES, LABEL_PRICE, LABEL_PRICE_PER_ITEM, LABEL_PRO_VERSION, LABEL_RECURSIVE_SUBSCRIPTION, LABEL_RED, LABEL_REPEAT_1, LABEL_REPEAT_2, LABEL_REPEAT_3, LABEL_REQUIRED, LABEL_RGB, LABEL_SELECT_ZPAD, LABEL_SELECTED_ZPAD, LABEL_SHARED_SUBSCRIPTION, LABEL_SHOWING_RESULT, LABEL_STARTPOINT, LABEL_SUBSCRIPTIONS, LABEL_SYSTEM_SUBSCRIPTIONS, LABEL_THIS_IS_HTML, LABEL_THIS_ZPAD, LABEL_TMPL_DESCRIPTOR, LABEL_TMPL_ID, LABEL_TMPL_LOOP, LABEL_TMPL_NOT_AVAILABLE, LABEL_TMPL_STUBCHARS, LABEL_TODAY, LABEL_TOPDOWN_SUBSCRIPTION, LABEL_TOTAL_PRICE, LABEL_TRANSLATION_URL, LABEL_UNCLASSIFIED, LABEL_UP_TO_USER, LABEL_USE_RANGE, LABEL_USER_NAME, LABEL_VOLUME_DISCOUNT, LABEL_WEEKLY, LABEL_WIDTH, LABEL_YEAR, LABEL_YEARLY, MARCH, MAY, MONDAY, MORE, NO_CONTENT_IN_PAGE, NOVEMBER, OCTOBER, PM, PRESSED_DATE_POPUP, PRESSED_EDIT_POPUP, PRESSED_FIND_POPUP, PRESSED_META_POPUP, PRESSED_PERSONALIZE_POPUP, PRESSED_PRIVL_POPUP, PRESSED_SECTION_POPUP, PRESSED_TOOLS_POPUP, QUESTION_ENTRY_TO_CLIPBOARD, QUESTION_OVERWRITE_BACKUP, QUESTION_REPLACE_WITH_BACKUP, QUESTION_SELECT_ADVANCED_VERSION, REMOVE, SATURDAY, SAVING_CONTENT, SEARCH_FOR_MANUAL, SEARCH_FOR_PRIVACY_LEVEL, SEARCH_FOR_PROVIDE_PL, SEARCH_FOR_RE_EXPORT, SEARCH_FOR_RE_MANUAL, SEARCH_FOR_SUBSCRIPTION, SEARCH_FOR_TIME, SEARCH_FOR_TYPE, SEPTEMBER, SHOULD_SYNC, SUNDAY, TEMPLATE_NOT_AVAILABLE, THURSDAY, TITLE_ADD_ALIAS, TITLE_ADD_APPLET, TITLE_ADD_EMBED, TITLE_ADD_HTML, TITLE_ADD_IMAGE, TITLE_ADD_IMPORT, TITLE_ADD_OBJECT, TITLE_ADD_TEXT, TITLE_ADD_TMPLD, TITLE_ADVANCED_ZPAD, TITLE_CHANGE_COVER, TITLE_CLABEL_DEFINITIONS, TITLE_CLABEL_SELECTION, TITLE_COPY_TO, TITLE_COVER_OPTIONS, TITLE_COVER_SECTIONS, TITLE_DATE_OFFSET, TITLE_DATE_SECTIONS, TITLE_DATE_SPEC, TITLE_DESTINATION, TITLE_EDIT_CATEGORIES, TITLE_EDIT_PRIVACY_GROUPS, TITLE_EDIT_SHEET, TITLE_ENTRY_ATTRIBS, TITLE_ENTRY_EXPIRATION, TITLE_ENTRY_INSPIRATION, TITLE_ENTRY_PARAMS, TITLE_ENTRY_PROPS, TITLE_EXPIRED_HANDLING, TITLE_EXTERNAL_SECTIONS, TITLE_FIND_ENTRY, TITLE_FIRST_SECTION, TITLE_IDENTIFY_YOURSELF, TITLE_INSTANT_COVER, TITLE_LAST_SECTION, TITLE_LOGIN_DIALOG, TITLE_MANIPULATE_SECTION, TITLE_MOVE_ENTRY, TITLE_MOVE_TO, TITLE_NAVIGATOR, TITLE_PERSONALIZE_SHEET, TITLE_PL_GROUPS, TITLE_REMOVE_ALIAS, TITLE_REMOVE_FILE, TITLE_REMOVE_IMAGE, TITLE_SELECT_DATE, TITLE_SELECT_PL, TITLE_SELECT_SECTION, TITLE_SELECT_TMPL, TITLE_SET_CLABEL_IMAGES, TITLE_SET_COLOR, TITLE_SET_COLORS, TITLE_SET_FRAME, TITLE_SET_HTML, TITLE_SET_PL, TITLE_START_SECTION, TITLE_STATISTICS, TITLE_SUBSCRIPTIONS, TITLE_TEMPLATE_PREFERENCE, TITLE_TOOLS_SHEET, TITLE_TRANSFER, TITLE_UPLOAD_FILE, TITLE_USER_SECTIONS, TO, TUESDAY, WEDNESDAY, ZPAD

Constructor Summary

WLZ7710()

Method Summary

ByteArrayOutputStream	deflate(byte[] data) ZPad uses 2 bytes for the Pointer, which consists of "B bytes back in the window, there is a match of L length".
protected ByteArrayOutputStream	deflate(byte[] data, int window, int satMatch, int maxMatch) The generic LZ77 compression algorithm
ByteArrayOutputStream	inflate(byte[] data) The ZPad specific LZ77 decompression algorithm.
protected void	loopmatch(byte[] data, int lookAhead, int window, int satMatch, int maxMatch) Find best match in the window preceding the current lookAhead.

Methods inherited from class java.lang.Object

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

Field Detail

WINDOW

public static final int WINDOW

See Also:

Constant Field Values

_position

protected int _position

_match

protected int _match

Constructor Detail

WLZ7710

public WLZ7710()

Method Detail

loopmatch

protected void loopmatch(byte[] data,
                         int lookAhead,
                         int window,
                         int satMatch,
                         int maxMatch)

Find best match in the window preceding the current lookAhead. (Irrelevant) optimilizations have been removed. They are totally neglectible compared to the effect of the compression parameters.

Parameters:

data - the total data to be compressed

lookAhead - the starting index of uncompressed data

window - the maximum number of bytes history parsed

satMatch - a match as large as satMatch will be returned immediately

maxMatch - the maximum match for a pointer compression

deflate

public ByteArrayOutputStream deflate(byte[] data)

ZPad uses 2 bytes for the Pointer, which consists of "B bytes back in the window, there is a match of L length". By reserving 6 bits for the length and 10 bits for offset, the maximum value for B is 2^10 = 1023 (!) and for L is 2^6 = 63 (!) This is the ZPad on average optimal balance between speed and compression.

deflate

protected ByteArrayOutputStream deflate(byte[] data,
                                        int window,
                                        int satMatch,
                                        int maxMatch)

The generic LZ77 compression algorithm

Parameters:

data - the data to be compressed

window - the amount of bytes to look back for matches

satMatch - a match as large as satMatch will be used immediately

maxMatch - the maximum match larger matches are cut to maxMatch

inflate

public ByteArrayOutputStream inflate(byte[] data)

The ZPad specific LZ77 decompression algorithm.