Package org.eclipse.jface.text

Class AbstractLineTracker

  • All Implemented Interfaces:
    ILineTracker, ILineTrackerExtension
    Direct Known Subclasses:
    ConfigurableLineTracker, DefaultLineTracker
    public abstract class AbstractLineTracker
extends Object
implements ILineTracker, ILineTrackerExtension
    Abstract implementation of ILineTracker. It lets the definition of line delimiters to subclasses. Assuming that '\n' is the only line delimiter, this abstract implementation defines the following line scheme:
    • "" -> [0,0]
    • "a" -> [0,1]
    • "\n" -> [0,1], [1,0]
    • "a\n" -> [0,2], [2,0]
    • "a\nb" -> [0,2], [2,1]
    • "a\nbc\n" -> [0,2], [2,3], [5,0]

    This class must be subclassed.

    • Constructor Detail

      • AbstractLineTracker

        protected AbstractLineTracker()
        Creates a new line tracker.

    • Method Detail

      • computeNumberOfLines

        public int computeNumberOfLines​(String text)
        Description copied from interface: ILineTracker
        Computes the number of lines in the given text.
        Specified by:
        computeNumberOfLines in interface ILineTracker
        Parameters:
        text - the text whose number of lines should be computed
        Returns:
        the number of lines in the given text

      • getLineDelimiter

        public String getLineDelimiter​(int line)
                        throws BadLocationException
        Description copied from interface: ILineTracker
        Returns the line delimiter of the specified line. Returns null if the line is not closed with a line delimiter.
        Specified by:
        getLineDelimiter in interface ILineTracker
        Parameters:
        line - the line whose line delimiter is queried
        Returns:
        the line's delimiter or null if line does not have a delimiter
        Throws:
        BadLocationException - if the line number is invalid in this tracker's line structure

      • getLineInformation

        public IRegion getLineInformation​(int line)
                           throws BadLocationException
        Description copied from interface: ILineTracker
        Returns a line description of the given line. The description contains the start offset and the length of the line excluding the line's delimiter.
        Specified by:
        getLineInformation in interface ILineTracker
        Parameters:
        line - the line that should be described
        Returns:
        a region describing the line
        Throws:
        BadLocationException - if line is unknown to this tracker

      • getLineInformationOfOffset

        public IRegion getLineInformationOfOffset​(int offset)
                                   throws BadLocationException
        Description copied from interface: ILineTracker
        Returns a line description of the line at the given offset. The description contains the start offset and the length of the line excluding the line's delimiter.
        Specified by:
        getLineInformationOfOffset in interface ILineTracker
        Parameters:
        offset - the offset whose line should be described
        Returns:
        a region describing the line
        Throws:
        BadLocationException - if offset is invalid in this tracker

      • getLineLength

        public int getLineLength​(int line)
                  throws BadLocationException
        Description copied from interface: ILineTracker
        Returns length of the specified line including the line's delimiter.
        Specified by:
        getLineLength in interface ILineTracker
        Parameters:
        line - the line of interest
        Returns:
        the length of the line
        Throws:
        BadLocationException - if line is unknown to this tracker

      • getLineNumberOfOffset

        public int getLineNumberOfOffset​(int offset)
                          throws BadLocationException
        Description copied from interface: ILineTracker
        Returns the line number the character at the given offset belongs to.
        Specified by:
        getLineNumberOfOffset in interface ILineTracker
        Parameters:
        offset - the offset whose line number to be determined
        Returns:
        the number of the line the offset is on
        Throws:
        BadLocationException - if the offset is invalid in this tracker

      • getLineOffset

        public int getLineOffset​(int line)
                  throws BadLocationException
        Description copied from interface: ILineTracker
        Returns the position of the first character of the specified line.
        Specified by:
        getLineOffset in interface ILineTracker
        Parameters:
        line - the line of interest
        Returns:
        offset of the first character of the line
        Throws:
        BadLocationException - if the line is unknown to this tracker

      • getNumberOfLines

        public int getNumberOfLines()
        Description copied from interface: ILineTracker
        Returns the number of lines.

        Note that a document always has at least one line.

        Specified by:
        getNumberOfLines in interface ILineTracker
        Returns:
        the number of lines in this tracker's line structure

      • getNumberOfLines

        public int getNumberOfLines​(int offset,
                            int length)
                     throws BadLocationException
        Description copied from interface: ILineTracker
        Returns the number of lines which are occupied by a given text range.
        Specified by:
        getNumberOfLines in interface ILineTracker
        Parameters:
        offset - the offset of the specified text range
        length - the length of the specified text range
        Returns:
        the number of lines occupied by the specified range
        Throws:
        BadLocationException - if specified range is unknown to this tracker

      • set

        public void set​(String text)
        Description copied from interface: ILineTracker
        Sets the tracked text to the specified text.
        Specified by:
        set in interface ILineTracker
        Parameters:
        text - the new tracked text

      • replace

        public void replace​(int offset,
                    int length,
                    String text)
             throws BadLocationException
        Description copied from interface: ILineTracker
        Informs the line tracker about the specified change in the tracked text.
        Specified by:
        replace in interface ILineTracker
        Parameters:
        offset - the offset of the replaced text
        length - the length of the replaced text
        text - the substitution text
        Throws:
        BadLocationException - if specified range is unknown to this tracker

      • nextDelimiterInfo

        protected abstract AbstractLineTracker.DelimiterInfo nextDelimiterInfo​(String text,
                                                                       int offset)
        Returns the information about the first delimiter found in the given text starting at the given offset.
        Parameters:
        text - the text to be searched
        offset - the offset in the given text
        Returns:
        the information of the first found delimiter or null

      • startRewriteSession

        public final void startRewriteSession​(DocumentRewriteSession session)
        Description copied from interface: ILineTrackerExtension
        Tells the line tracker that a rewrite session started. A rewrite session is a sequence of replace operations that form a semantic unit. The line tracker is allowed to use that information for internal optimization.
        Specified by:
        startRewriteSession in interface ILineTrackerExtension
        Parameters:
        session - the rewrite session

      • stopRewriteSession

        public final void stopRewriteSession​(DocumentRewriteSession session,
                                     String text)
        Description copied from interface: ILineTrackerExtension
        Tells the line tracker that the rewrite session has finished. This method is only called when startRewriteSession has been called before. The text resulting from the rewrite session is passed to the line tracker.
        Specified by:
        stopRewriteSession in interface ILineTrackerExtension
        Parameters:
        session - the rewrite session
        text - the text with which to re-initialize the line tracker

      • hasActiveRewriteSession

        protected final boolean hasActiveRewriteSession()
        Tells whether there's an active rewrite session.
        Returns:
        true if there is an active rewrite session, false otherwise
        Since:
        3.1

      • flushRewriteSession

        protected final void flushRewriteSession()
                                  throws BadLocationException
        Flushes the active rewrite session.
        Throws:
        BadLocationException - in case the recorded requests cannot be processed correctly
        Since:
        3.1

      • checkRewriteSession

        protected final void checkRewriteSession()
                                  throws BadLocationException
        Checks the presence of a rewrite session and flushes it.
        Throws:
        BadLocationException - in case flushing does not succeed
        Since:
        3.1