org.kde.koala
Class KBufferedIO

java.lang.Object
  extended by org.kde.qt.Qt
      extended by org.kde.qt.QObject
          extended by org.kde.koala.KAsyncIO
              extended by org.kde.koala.KBufferedIO
All Implemented Interfaces:
org.kde.qt.QIODeviceInterface, org.kde.qt.QtSupport

public class KBufferedIO
extends KAsyncIO

This abstract class implements basic functionality for buffered input/output. Through the available methods, you can find out how many bytes are available for reading, how many are still unsent and you can peek at the buffered data. This class was intentionally written to resemble QSocket, because KExtendedSocket is a subclass of this one. This is so that applications written using QSocket's buffering characteristics will be more easily ported to the more powerful KExtendedSocket class. KBufferedIO already provides a powerful internal buffering algorithm. However, this does not include the I/O itself, which must be implemented in derived classes. Thus, to implement a class that does some I/O, you must override, in addition to the pure QIODevice methods, these two:

  • closeNow()
  • waitForMore()
  • If your derived class reimplements the buffering algorithm, you must then decide which buffering functions to override. For instance, you may want to change the protected functions like feedReadBuffer() and consumeReadBuffer(). See KBufferedIOSignals for signals emitted by KBufferedIO

    Author:
    Thiago Macieira

    Field Summary
    static int availRead
              The modes for closed() signal
    static int closedNow
               
    static int delayed
               
    static int dirtyWrite
               
    static int involuntary
               
     
    Fields inherited from class org.kde.qt.Qt
    AlignAuto, AlignBottom, AlignCenter, AlignHCenter, AlignHorizontal_Mask, AlignJustify, AlignLeft, AlignRight, AlignTop, AlignVCenter, AlignVertical_Mask, AlphaDither_Mask, ALT, AltButton, AnchorHref, AnchorName, AndNotROP, AndROP, ArrowCursor, Ascending, ASCII_ACCEL, AutoColor, AutoDither, AutoText, AvoidDither, BDiagPattern, BeginsWith, BevelJoin, BitmapCursor, BlankCursor, Bottom, BottomLeft, BottomRight, BreakAnywhere, BusyCursor, CaseSensitive, ClearROP, ColorMode_Mask, ColorOnly, Contains, ControlButton, CopyROP, CrossCursor, CrossPattern, CTRL, CustomPattern, DashDotDotLine, DashDotLine, DashLine, Dense1Pattern, Dense2Pattern, Dense3Pattern, Dense4Pattern, Dense5Pattern, Dense6Pattern, Dense7Pattern, Descending, DiagCrossPattern, DiffuseAlphaDither, DiffuseDither, Dither_Mask, DitherMode_Mask, DockBottom, DockLeft, DockMinimized, DockRight, DockTop, DockTornOff, DockUnmanaged, DontClip, DontPrint, DotLine, DownArrow, EndsWith, EraseROP, ExactMatch, ExpandTabs, FDiagPattern, FixedColor, FixedPixmap, FlatCap, ForbiddenCursor, HiEnglishUnit, HiMetricUnit, Horizontal, HorPattern, IbeamCursor, Identical, IncludeTrailingSpaces, ISODate, Key_0, Key_1, Key_2, Key_3, Key_4, Key_5, Key_6, Key_7, Key_8, Key_9, Key_A, Key_aacute, Key_Aacute, Key_acircumflex, Key_Acircumflex, Key_acute, Key_adiaeresis, Key_Adiaeresis, Key_ae, Key_AE, Key_agrave, Key_Agrave, Key_Alt, Key_Ampersand, Key_Any, Key_Apostrophe, Key_aring, Key_Aring, Key_AsciiCircum, Key_AsciiTilde, Key_Asterisk, Key_At, Key_atilde, Key_Atilde, Key_B, Key_Back, Key_Backslash, Key_Backspace, Key_BackSpace, Key_Backtab, Key_BackTab, Key_Bar, Key_BassBoost, Key_BassDown, Key_BassUp, Key_BraceLeft, Key_BraceRight, Key_BracketLeft, Key_BracketRight, Key_brokenbar, Key_C, Key_CapsLock, Key_ccedilla, Key_Ccedilla, Key_cedilla, Key_cent, Key_Clear, Key_Colon, Key_Comma, Key_Control, Key_copyright, Key_currency, Key_D, Key_degree, Key_Delete, Key_diaeresis, Key_Direction_L, Key_Direction_R, Key_division, Key_Dollar, Key_Down, Key_E, Key_eacute, Key_Eacute, Key_ecircumflex, Key_Ecircumflex, Key_ediaeresis, Key_Ediaeresis, Key_egrave, Key_Egrave, Key_End, Key_Enter, Key_Equal, Key_Escape, Key_eth, Key_ETH, Key_Exclam, Key_exclamdown, Key_F, Key_F1, Key_F10, Key_F11, Key_F12, Key_F13, Key_F14, Key_F15, Key_F16, Key_F17, Key_F18, Key_F19, Key_F2, Key_F20, Key_F21, Key_F22, Key_F23, Key_F24, Key_F25, Key_F26, Key_F27, Key_F28, Key_F29, Key_F3, Key_F30, Key_F31, Key_F32, Key_F33, Key_F34, Key_F35, Key_F4, Key_F5, Key_F6, Key_F7, Key_F8, Key_F9, Key_Favorites, Key_Forward, Key_G, Key_Greater, Key_guillemotleft, Key_guillemotright, Key_H, Key_Help, Key_Home, Key_HomePage, Key_Hyper_L, Key_Hyper_R, Key_hyphen, Key_I, Key_iacute, Key_Iacute, Key_icircumflex, Key_Icircumflex, Key_idiaeresis, Key_Idiaeresis, Key_igrave, Key_Igrave, Key_Insert, Key_J, Key_K, Key_L, Key_Launch0, Key_Launch1, Key_Launch2, Key_Launch3, Key_Launch4, Key_Launch5, Key_Launch6, Key_Launch7, Key_Launch8, Key_Launch9, Key_LaunchA, Key_LaunchB, Key_LaunchC, Key_LaunchD, Key_LaunchE, Key_LaunchF, Key_LaunchMail, Key_LaunchMedia, Key_Left, Key_Less, Key_M, Key_macron, Key_masculine, Key_MediaLast, Key_MediaNext, Key_MediaPlay, Key_MediaPrev, Key_MediaRecord, Key_MediaStop, Key_Menu, Key_Meta, Key_Minus, Key_mu, Key_multiply, Key_N, Key_Next, Key_nobreakspace, Key_notsign, Key_ntilde, Key_Ntilde, Key_NumberSign, Key_NumLock, Key_O, Key_oacute, Key_Oacute, Key_ocircumflex, Key_Ocircumflex, Key_odiaeresis, Key_Odiaeresis, Key_ograve, Key_Ograve, Key_onehalf, Key_onequarter, Key_onesuperior, Key_Ooblique, Key_OpenUrl, Key_ordfeminine, Key_oslash, Key_otilde, Key_Otilde, Key_P, Key_PageDown, Key_PageUp, Key_paragraph, Key_ParenLeft, Key_ParenRight, Key_Pause, Key_Percent, Key_Period, Key_periodcentered, Key_Plus, Key_plusminus, Key_Print, Key_Prior, Key_Q, Key_Question, Key_questiondown, Key_QuoteDbl, Key_QuoteLeft, Key_R, Key_Refresh, Key_registered, Key_Return, Key_Right, Key_S, Key_ScrollLock, Key_Search, Key_section, Key_Semicolon, Key_Shift, Key_Slash, Key_Space, Key_ssharp, Key_Standby, Key_sterling, Key_Stop, Key_Super_L, Key_Super_R, Key_SysReq, Key_T, Key_Tab, Key_thorn, Key_THORN, Key_threequarters, Key_threesuperior, Key_TrebleDown, Key_TrebleUp, Key_twosuperior, Key_U, Key_uacute, Key_Uacute, Key_ucircumflex, Key_Ucircumflex, Key_udiaeresis, Key_Udiaeresis, Key_ugrave, Key_Ugrave, Key_Underscore, Key_unknown, Key_Up, Key_V, Key_VolumeDown, Key_VolumeMute, Key_VolumeUp, Key_W, Key_X, Key_Y, Key_yacute, Key_Yacute, Key_ydiaeresis, Key_yen, Key_Z, KeyButtonMask, Keypad, LastCursor, LastROP, Left, LeftArrow, LeftButton, LocalDate, LocalTime, LoEnglishUnit, LogText, LoMetricUnit, MacStyle, META, MetaButton, MidButton, Minimized, MiterJoin, MODIFIER_MASK, MonoOnly, MotifStyle, MouseButtonMask, MPenCapStyle, MPenJoinStyle, MPenStyle, MV_10_DOT_0, MV_10_DOT_1, MV_10_DOT_2, MV_10_DOT_3, MV_10_DOT_4, MV_9, MV_CHEETAH, MV_JAGUAR, MV_PANTHER, MV_PUMA, MV_TIGER, MV_Unknown, NandROP, NoAccel, NoAlpha, NoBackground, NoBrush, NoButton, NoMatch, NoPen, NopROP, NorROP, NotAndROP, NotCopyROP, NotEraseROP, NotOrROP, NotROP, NotXorROP, OpaqueMode, OrderedAlphaDither, OrderedDither, OrNotROP, OrROP, Overline, PaletteBackground, PaletteBase, PaletteBrightText, PaletteButton, PaletteButtonText, PaletteDark, PaletteForeground, PaletteHighlight, PaletteHighlightedText, PaletteLight, PaletteLink, PaletteLinkVisited, PaletteMid, PaletteMidlight, PaletteShadow, PaletteText, PartialMatch, PixelUnit, PlainText, PMStyle, PointingHandCursor, PreferDither, RichText, Right, RightArrow, RightButton, RoundCap, RoundJoin, SetROP, SHIFT, ShiftButton, ShowPrefix, SingleLine, SizeAllCursor, SizeBDiagCursor, SizeFDiagCursor, SizeHorCursor, SizeVerCursor, SolidLine, SolidPattern, SplitHCursor, SplitVCursor, SquareCap, StrikeOut, TextDate, ThresholdAlphaDither, ThresholdDither, Top, TopLeft, TopRight, TornOff, TransparentMode, TwipsUnit, UI_AnimateCombo, UI_AnimateMenu, UI_AnimateToolBox, UI_AnimateTooltip, UI_FadeMenu, UI_FadeTooltip, UI_General, Underline, UNICODE_ACCEL, Unmanaged, UpArrow, UpArrowCursor, UTC, VerPattern, Vertical, WaitCursor, WDestructiveClose, WGroupLeader, WhatsThisCursor, Win3Style, WindowActive, WindowFullScreen, WindowMaximized, WindowMinimized, WindowNoState, WindowsStyle, WMacDrawer, WMacNoSheet, WMouseNoMask, WNoAutoErase, WNoMousePropagation, WNorthWestGravity, WordBreak, WPaintClever, WPaintDesktop, WPaintUnclipped, WRepaintNoErase, WResizeNoErase, WShowModal, WState_AutoMask, WState_BlockUpdates, WState_CompressKeys, WState_ConfigPending, WState_Created, WState_CreatedHidden, WState_Disabled, WState_DND, WState_Exposed, WState_ForceDisabled, WState_ForceHide, WState_FullScreen, WState_HasMouse, WState_InPaintEvent, WState_Maximized, WState_Minimized, WState_MouseTracking, WState_OwnCursor, WState_OwnSizePolicy, WState_Polished, WState_Reparented, WState_Reserved0, WState_Resized, WState_Visible, WStaticContents, WStyle_ContextHelp, WStyle_Customize, WStyle_Dialog, WStyle_DialogBorder, WStyle_Mask, WStyle_Maximize, WStyle_Minimize, WStyle_MinMax, WStyle_NoBorder, WStyle_NoBorderEx, WStyle_NormalBorder, WStyle_Reserved, WStyle_Splash, WStyle_StaysOnTop, WStyle_SysMenu, WStyle_Title, WStyle_Tool, WSubWindow, WType_Desktop, WType_Dialog, WType_Mask, WType_Modal, WType_Popup, WType_TopLevel, WV_2000, WV_2003, WV_32s, WV_95, WV_98, WV_CE, WV_CE_based, WV_CENET, WV_DOS_based, WV_Me, WV_NT, WV_NT_based, WV_XP, WWinOwnDC, WX11BypassWM, X11ParentRelative, XorROP
     
    Constructor Summary
    protected KBufferedIO(java.lang.Class dummy)
               
     
    Method Summary
     int bytesAvailable()
              Returns the number of bytes available for reading in the read buffer
     int bytesToWrite()
              Returns the number of bytes yet to write, still in the write buffer
     boolean canReadLine()
              Checks whether there is enough data in the buffer to read a line The default implementation reads directly from inBuf, so if your implementation changes the meaning of that member, then you must override this function.
     java.lang.String className()
               
     void closeNow()
              Closes the stream now, discarding the contents of the write buffer.
     org.kde.qt.QMetaObject metaObject()
               
     int peekBlock(java.lang.String data, int maxlen)
              Reads into the user buffer at most maxlen bytes, but does not consume that data from the read buffer.
     boolean setBufferSize(int rsize)
               
     boolean setBufferSize(int rsize, int wsize)
              Sets the internal buffer size to value.
     int unreadBlock(java.lang.String data, int len)
              Unreads some data.
     int waitForMore(int msec)
              Waits for more data to be available and returns the amount of available data then.
     
    Methods inherited from class org.kde.koala.KAsyncIO
    at, at, atEnd, close, enableRead, enableWrite, flags, flush, getch, isAsynchronous, isBuffered, isCombinedAccess, isDirectAccess, isInactive, isOpen, isRaw, isReadable, isReadWrite, isSequentialAccess, isSynchronous, isTranslated, isWritable, mode, open, putch, readAll, readBlock, readLine, reset, resetStatus, size, state, status, ungetch, writeBlock, writeBlock
     
    Methods inherited from class org.kde.qt.QObject
    activate_filters, activate_signal_bool, activate_signal, activate_signal, activate_signal, activate_signal, blockSignals, checkConnectArgs, child, child, child, childEvent, children, connect, connect, connectInternal, connectNotify, customEvent, deleteLater, disconnect, disconnect, disconnect, disconnect, disconnect, disconnect, disconnect, disconnectInternal, disconnectNotify, dispose, dumpObjectInfo, dumpObjectTree, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, emit, event, eventFilter, finalize, highPriority, i18n, inherits, insertChild, installEventFilter, isA, isDisposed, isWidgetType, killTimer, killTimers, name, name, normalizeSignalSlot, objectTrees, parent, property, queryList, queryList, queryList, queryList, queryList, registerUserData, removeChild, removeEventFilter, sender, setName, setProperty, signalsBlocked, startTimer, timerEvent, tr, tr
     
    Methods inherited from class org.kde.qt.Qt
    arrowCursor, bin, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, bitBlt, black, blankCursor, blue, color0, color1, copyBlt, copyBlt, copyBlt, copyBlt, copyBlt, crossCursor, cyan, darkBlue, darkCyan, darkGray, darkGreen, darkMagenta, darkRed, darkYellow, dec, dynamicCast, endl, flush, forbiddenCursor, fromUtf8, gray, green, hex, ibeamCursor, lightGray, magenta, oct, op_div, op_div, op_div, op_div, op_equals, op_equals, op_equals, op_equals, op_minus, op_minus, op_minus, op_mult, op_mult, op_mult, op_mult, op_mult, op_mult, op_mult, op_mult, op_mult, op_not_equals, op_not_equals, op_not_equals, op_not_equals, op_plus, op_plus, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_read, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, op_write, pointingHandCursor, qAlpha, qApp, qAppName, qBlue, qCompress, qCompress, qDebug, qDebug, qDrawArrow, qDrawItem, qDrawItem, qDrawItem, qDrawPlainRect, qDrawPlainRect, qDrawPlainRect, qDrawPlainRect, qDrawPlainRect, qDrawPlainRect, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadeLine, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadePanel, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawShadeRect, qDrawWinButton, qDrawWinButton, qDrawWinButton, qDrawWinButton, qDrawWinButton, qDrawWinButton, qDrawWinPanel, qDrawWinPanel, qDrawWinPanel, qDrawWinPanel, qDrawWinPanel, qDrawWinPanel, qFatal, qFatal, qGLVersion, qGray, qGray, qGreen, qInitNetworkProtocols, qInstallPath, qInstallPathBins, qInstallPathData, qInstallPathDocs, qInstallPathHeaders, qInstallPathLibs, qInstallPathPlugins, qInstallPathSysconf, qInstallPathTranslations, qItemRect, qItemRect, qObsolete, qObsolete, qObsolete, qRed, qRgb, qRgba, qRound, qSharedBuild, qSuppressObsoleteWarnings, qSuppressObsoleteWarnings, qSysInfo, qSystemWarning, qSystemWarning, qUncompress, qUncompress, qVersion, qWarning, qWarning, red, reset, SIGNAL, sizeAllCursor, sizeBDiagCursor, sizeFDiagCursor, sizeHorCursor, sizeVerCursor, SLOT, splitHCursor, splitVCursor, upArrowCursor, waitCursor, whatsThisCursor, white, ws, yellow
     
    Methods inherited from class java.lang.Object
    clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
     

    Field Detail

    availRead

    public static final int availRead
    The modes for closed() signal

    See Also:
    Constant Field Values

    dirtyWrite

    public static final int dirtyWrite
    See Also:
    Constant Field Values

    involuntary

    public static final int involuntary
    See Also:
    Constant Field Values

    delayed

    public static final int delayed
    See Also:
    Constant Field Values

    closedNow

    public static final int closedNow
    See Also:
    Constant Field Values
    Constructor Detail

    KBufferedIO

    protected KBufferedIO(java.lang.Class dummy)
    Method Detail

    metaObject

    public org.kde.qt.QMetaObject metaObject()
    Overrides:
    metaObject in class KAsyncIO

    className

    public java.lang.String className()
    Overrides:
    className in class KAsyncIO

    closeNow

    public void closeNow()
    Closes the stream now, discarding the contents of the write buffer. That is, we won't try to flush that buffer before closing. If you want that buffer to be flushed, you can call QIODevice.flush(), which is blocking, and then closeNow, or you can call QIODevice.close() for a delayed close.


    setBufferSize

    public boolean setBufferSize(int rsize,
                                 int wsize)
    Sets the internal buffer size to value. Not all implementations support this. The parameters may be 0 to make the class unbuffered or -1 to let the class choose the size (which may be unlimited) or -2 to leave the buffer size untouched. Note that setting the write buffer size to any value smaller than the current size of the buffer will force it to flush first, which can make this call blocking. The default implementation does not support setting the buffer sizes. You can only call this function with values -1 for "don't care" or -2 for "unchanged"

    Parameters:
    rsize - the size of the read buffer
    wsize - the size of the write buffer
    Returns:
    true if setting both was ok. If false is returned, the buffers were left unchanged.

    setBufferSize

    public boolean setBufferSize(int rsize)

    bytesAvailable

    public int bytesAvailable()
    Returns the number of bytes available for reading in the read buffer

    Returns:
    the number of bytes available for reading

    waitForMore

    public int waitForMore(int msec)
    Waits for more data to be available and returns the amount of available data then.

    Parameters:
    msec - number of milliseconds to wait, -1 to wait forever
    Returns:
    -1 if we cannot wait (e.g., that doesn't make sense in this stream)

    bytesToWrite

    public int bytesToWrite()
    Returns the number of bytes yet to write, still in the write buffer

    Returns:
    the number of unwritten bytes in the write buffer

    canReadLine

    public boolean canReadLine()
    Checks whether there is enough data in the buffer to read a line The default implementation reads directly from inBuf, so if your implementation changes the meaning of that member, then you must override this function.

    Returns:
    true when there is enough data in the buffer to read a line

    peekBlock

    public int peekBlock(java.lang.String data,
                         int maxlen)
    Reads into the user buffer at most maxlen bytes, but does not consume that data from the read buffer. This is useful to check whether we already have the needed data to process something. This function may want to try and read more data from the system provided it won't block.

    Parameters:
    data - the user buffer pointer, at least maxlen bytes long
    maxlen - the maximum length to be peeked
    Returns:
    the number of bytes actually copied.

    unreadBlock

    public int unreadBlock(java.lang.String data,
                           int len)
    Unreads some data. That is, write the data to the beginning of the read buffer, so that next calls to readBlock or peekBlock will see this data instead. Note not all devices implement this since this could mean a semantic problem. For instance, sockets are sequential devices, so they won't accept unreading.

    Parameters:
    data - the data to be unread
    len - the size of the data
    Returns:
    the number of bytes actually unread