## org.gjt.sp.jedit.buffer
Class JEditBuffer

    java.lang.Object
      org.gjt.sp.jedit.buffer.JEditBuffer

Direct Known Subclasses:
  Buffer

    public class JEditBuffer

extends java.lang.Object

A `JEditBuffer` represents the contents of an open text file as it is maintained in the computer's memory (as opposed to how it may be stored on a disk).

This class is partially thread-safe, however you must pay attention to two very important guidelines:

- Changes to a buffer can only be made from the AWT thread.
- When accessing the buffer from another thread, you must grab a read lock if you plan on performing more than one call, to ensure that the buffer contents are not changed by the AWT thread for the duration of the lock. Only methods whose descriptions specify thread safety can be invoked from other threads.

Since:
  jEdit 4.3pre3

Nested Class Summary
`protected static class` `JEditBuffer.PropValue`

Field Summary
`static java.lang.String` `ENCODING` Character encoding used when loading and saving.
`static int` `HIGH_PRIORITY`
`static java.lang.String` `LINESEP` Line separator property.
`protected Mode` `mode`
`static int` `NORMAL_PRIORITY`
`protected boolean` `textMode`
`protected UndoManager` `undoMgr`

Constructor Summary
`JEditBuffer()` Create a new JEditBuffer.
`JEditBuffer(java.util.Map props)`

Method Summary
`void` `addBufferListener(BufferListener listener)` Adds a buffer change listener.
`void` `addBufferListener(BufferListener listener, int priority)` Adds a buffer change listener.
`void` `beginCompoundEdit()` Starts a compound edit.
`boolean` `canRedo()` Returns true if a redo operation can be performed.
`boolean` `canUndo()` Returns true if an undo operation can be performed.
`javax.swing.text.Position` `createPosition(int offset)` Creates a floating position.
`void` `endCompoundEdit()` Ends a compound edit.
`protected void` `fireBeginRedo()`
`protected void` `fireBeginUndo()`
`protected void` `fireBufferLoaded()`
`protected void` `fireContentInserted(int startLine, int offset, int numLines, int length)`
`protected void` `fireContentRemoved(int startLine, int offset, int numLines, int length)`
`protected void` `fireEndRedo()`
`protected void` `fireEndUndo()`
`protected void` `fireFoldHandlerChanged()`
`protected void` `fireFoldLevelChanged(int start, int end)`
`protected void` `firePreContentInserted(int startLine, int offset, int numLines, int length)`
`protected void` `firePreContentRemoved(int startLine, int offset, int numLines, int length)`
`protected void` `fireTransactionComplete()`
`boolean` `getBooleanProperty(java.lang.String name)` Returns the value of a boolean property.
`boolean` `getBooleanProperty(java.lang.String name, boolean def)` Returns the value of a boolean property.
`BufferListener[]` `getBufferListeners()` Returns an array of registered buffer change listeners.
`java.lang.String` `getContextSensitiveProperty(int offset, java.lang.String name)` Some settings, like comment start and end strings, can vary between different parts of a buffer (HTML text and inline JavaScript, for example).
`int` `getCurrentIndentForLine(int lineIndex, int[] whitespaceChars)` Returns the line's current leading indent.
`java.lang.Object` `getDefaultProperty(java.lang.String key)`
`int[]` `getFoldAtLine(int line)` Returns an array.
`FoldHandler` `getFoldHandler()` Returns the current buffer's fold handler.
`int` `getFoldLevel(int line)` Returns the fold level of the specified line.
`int` `getIdealIndentForLine(int lineIndex)` Returns the ideal leading indent for the specified line.
`int` `getIndentSize()` Returns the indent size used in this buffer.
`int` `getIntegerProperty(java.lang.String name, int defaultValue)` Returns the value of an integer property.
`KeywordMap` `getKeywordMapAtOffset(int offset)` Returns the syntax highlighting keyword map in effect at the specified offset.
`int` `getLength()` Returns the number of characters in the buffer.
`int` `getLineCount()` Returns the number of physical lines in the buffer.
`int` `getLineEndOffset(int line)` Returns the end offset of the specified line.
`int` `getLineLength(int line)` Returns the length of the specified line.
`int` `getLineOfOffset(int offset)` Returns the line containing the specified offset.
`java.lang.CharSequence` `getLineSegment(int line)` Returns the text on the specified line.
`int` `getLineStartOffset(int line)` Returns the start offset of the specified line.
`java.lang.String` `getLineText(int line)` Returns the text on the specified line.
`void` `getLineText(int line, javax.swing.text.Segment segment)` Returns the specified line in a `Segment`.
`Mode` `getMode()` Returns this buffer's edit mode.
`int` `getOffsetOfVirtualColumn(int line, int column, int[] totalVirtualWidth)` Returns the offset of a virtual column number (taking tabs into account) relative to the start of the line in question.
`java.util.regex.Pattern` `getPatternProperty(java.lang.String name, int flags)` Returns the value of a property as a regular expression.
`int` `getPriorNonEmptyLine(int lineIndex)` Auto indent needs this.
`java.lang.Object` `getProperty(java.lang.Object name)` Returns the value of a buffer-local property.
`ParserRuleSet` `getRuleSetAtOffset(int offset)` Returns the syntax highlighting ruleset at the specified offset.
`java.lang.CharSequence` `getSegment(int start, int length)` Returns the specified text range.
`java.lang.String` `getStringProperty(java.lang.String name)` Returns the value of a string property.
`int` `getTabSize()` Returns the tab size used in this buffer.
`java.lang.String` `getText(int start, int length)` Returns the specified text range.
`void` `getText(int start, int length, javax.swing.text.Segment seg)` Returns the specified text range in a `Segment`.
`TokenMarker` `getTokenMarker()`
`java.lang.Object` `getUndoId()` Returns an object that identifies the undo operation to which the current content change belongs.
`int` `getVirtualWidth(int line, int column)` Returns the virtual column number (taking tabs into account) of the specified position.
`boolean` `indentLine(int lineIndex, boolean canDecreaseIndent)` Indents the specified line.
`boolean` `indentLine(int lineIndex, boolean canIncreaseIndent, boolean canDecreaseIndent)` Deprecated. Use `indentLine(int,boolean)` instead.
`void` `indentLines(int[] lines)` Indents all specified lines.
`void` `indentLines(int start, int end)` Indents all specified lines.
`void` `insert(int offset, javax.swing.text.Segment seg)` Inserts a string into the buffer.
`void` `insert(int offset, java.lang.String str)` Inserts a string into the buffer.
`void` `insertAtColumn(int line, int col, java.lang.String str)` Like the `insert(int,String)` method, but inserts the string at the specified virtual column.
`int` `insertIndented(int offset, java.lang.String text)` Inserts a string into the buffer, indenting each line of the string to match the indent of the first line.
`boolean` `insideCompoundEdit()` Returns if a compound edit is currently active.
`void` `invalidateCachedFoldLevels()` Invalidates all cached fold level information.
`protected void` `invalidateFoldLevels()`
`boolean` `isDirty()` Returns whether there have been unsaved changes to this buffer.
`boolean` `isEditable()` Returns true if this file is editable, false otherwise.
`boolean` `isElectricKey(char ch)` Deprecated. Use #isElectricKey(char,int)
`boolean` `isElectricKey(char ch, int line)` Should inserting this character trigger a re-indent of the current line?
`protected boolean` `isFileReadOnly()`
`boolean` `isFoldEnd(int line)` Returns if the specified line ends a fold.
`boolean` `isFoldStart(int line)` Returns if the specified line begins a fold.
`boolean` `isLoading()`
`boolean` `isPerformingIO()` Returns true if the buffer is currently performing I/O.
`boolean` `isReadOnly()` Returns true if this file is read only, false otherwise.
`boolean` `isTransactionInProgress()` Returns if an undo or compound edit is currently in progress.
`boolean` `isUndoInProgress()` Returns if an undo or redo is currently being performed.
`protected void` `loadText(javax.swing.text.Segment seg, IntegerArray endOffsets)`
`void` `markTokens(int lineIndex, TokenHandler tokenHandler)` Returns the syntax tokens for the specified line.
`protected void` `parseBufferLocalProperties()`
`void` `propertiesChanged()` Reloads settings from the properties.
`void` `readLock()` The buffer is guaranteed not to change between calls to `readLock()` and `readUnlock()`.
`void` `readUnlock()` The buffer is guaranteed not to change between calls to `readLock()` and `readUnlock()`.
`void` `redo(TextArea textArea)` Redoes the most recently undone edit.
`void` `remove(int offset, int length)` Removes the specified rang efrom the buffer.
`void` `removeBufferListener(BufferListener listener)` Removes a buffer change listener.
`void` `removeTrailingWhiteSpace(int[] lines)` Removes trailing whitespace from all lines in the specified list.
`void` `resetCachedProperties()`
`void` `setBooleanProperty(java.lang.String name, boolean value)` Sets a boolean property.
`void` `setDefaultProperty(java.lang.String name, java.lang.Object value)`
`void` `setDirty(boolean d)` Sets the 'dirty' (changed since last save) flag of this buffer.
`protected void` `setFileReadOnly(boolean readOnly)`
`void` `setFoldHandler(FoldHandler foldHandler)` Sets the buffer's fold handler.
`void` `setIntegerProperty(java.lang.String name, int value)` Sets an integer property.
`void` `setLoading(boolean loading)`
`void` `setMode(Mode mode)` Sets this buffer's edit mode.
`void` `setMode(java.lang.String mode)` Sets this buffer's edit mode.
`void` `setPerformingIO(boolean io)` Returns true if the buffer is currently performing I/O.
`void` `setProperty(java.lang.String name, java.lang.Object value)` Sets the value of a buffer-local property.
`void` `setReadOnly(boolean readOnly)` Sets the read only flag.
`void` `setStringProperty(java.lang.String name, java.lang.String value)` Sets a string property.
`void` `setTokenMarker(TokenMarker tokenMarker)`
`void` `setUndoLimit(int limit)` Set the undo limit of the Undo Manager.
`void` `shiftIndentLeft(int[] lines)` Shifts the indent of each line in the specified list to the left.
`void` `shiftIndentRight(int[] lines)` Shifts the indent of each line in the specified list to the right.
`void` `undo(TextArea textArea)` Undoes the most recent edit.
`void` `unsetProperty(java.lang.String name)` Clears the value of a buffer-local property.
`void` `writeLock()` Attempting to obtain read lock will block between calls to `writeLock()` and `writeUnlock()`.
`void` `writeUnlock()` Attempting to obtain read lock will block between calls to `writeLock()` and `writeUnlock()`.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### LINESEP

    public static final java.lang.String LINESEP

  Line separator property.

  See Also:
    Constant Field Values

### ENCODING

    public static final java.lang.String ENCODING

  Character encoding used when loading and saving.

  Since:
    jEdit 3.2pre4
  See Also:
    Constant Field Values

### NORMAL_PRIORITY

    public static final int NORMAL_PRIORITY

See Also:
  Constant Field Values

### HIGH_PRIORITY

    public static final int HIGH_PRIORITY

See Also:
  Constant Field Values

### mode

    protected Mode mode

### textMode

    protected boolean textMode

### undoMgr

    protected UndoManager undoMgr

Constructor Detail

### JEditBuffer

    public JEditBuffer(java.util.Map props)

### JEditBuffer

    public JEditBuffer()

  Create a new JEditBuffer. It is used by independent textarea only

Method Detail

### isDirty

    public boolean isDirty()

  Returns whether there have been unsaved changes to this buffer. This method is thread-safe.

### isLoading

    public boolean isLoading()

### setLoading

    public void setLoading(boolean loading)

### isPerformingIO

    public boolean isPerformingIO()

  Returns true if the buffer is currently performing I/O. This method is thread-safe.

  Since:
    jEdit 2.7pre1

### setPerformingIO

    public void setPerformingIO(boolean io)

  Returns true if the buffer is currently performing I/O. This method is thread-safe.

  Since:
    jEdit 2.7pre1

### isEditable

    public boolean isEditable()

  Returns true if this file is editable, false otherwise. A file may become uneditable if it is read only, or if I/O is in progress. This method is thread-safe.

  Since:
    jEdit 2.7pre1

### isReadOnly

    public boolean isReadOnly()

  Returns true if this file is read only, false otherwise. This method is thread-safe.

### setReadOnly

    public void setReadOnly(boolean readOnly)

  Sets the read only flag.

  Parameters:
    `readOnly` - The read only flag

### setDirty

    public void setDirty(boolean d)

  Sets the 'dirty' (changed since last save) flag of this buffer.

### readLock

    public void readLock()

  The buffer is guaranteed not to change between calls to `readLock()` and `readUnlock()`.

### readUnlock

    public void readUnlock()

  The buffer is guaranteed not to change between calls to `readLock()` and `readUnlock()`.

### writeLock

    public void writeLock()

  Attempting to obtain read lock will block between calls to `writeLock()` and `writeUnlock()`.

### writeUnlock

    public void writeUnlock()

  Attempting to obtain read lock will block between calls to `writeLock()` and `writeUnlock()`.

### getLength

    public int getLength()

  Returns the number of characters in the buffer. This method is thread-safe.

### getLineCount

    public int getLineCount()

  Returns the number of physical lines in the buffer. This method is thread-safe.

  Since:
    jEdit 3.1pre1

### getLineOfOffset

    public int getLineOfOffset(int offset)

  Returns the line containing the specified offset. This method is thread-safe.

  Parameters:
    `offset` - The offset
  Since:
    jEdit 4.0pre1

### getLineStartOffset

    public int getLineStartOffset(int line)

  Returns the start offset of the specified line. This method is thread-safe.

  Parameters:
    `line` - The line
  Returns:
    The start offset of the specified line
  Since:
    jEdit 4.0pre1

### getLineEndOffset

    public int getLineEndOffset(int line)

  Returns the end offset of the specified line. This method is thread-safe.

  Parameters:
    `line` - The line
  Returns:
    The end offset of the specified line invalid.
  Since:
    jEdit 4.0pre1

### getLineLength

    public int getLineLength(int line)

  Returns the length of the specified line. This method is thread-safe.

  Parameters:
    `line` - The line
  Since:
    jEdit 4.0pre1

### getPriorNonEmptyLine

    public int getPriorNonEmptyLine(int lineIndex)

  Auto indent needs this.

### getLineText

    public java.lang.String getLineText(int line)

  Returns the text on the specified line. This method is thread-safe.

  Parameters:
    `line` - The line
  Returns:
    The text, or null if the line is invalid
  Since:
    jEdit 4.0pre1

### getLineText

    public void getLineText(int line,
                            javax.swing.text.Segment segment)

  Returns the specified line in a `Segment`.

  Using a <classname>Segment</classname> is generally more efficient than using a <classname>String</classname> because it results in less memory allocation and array copying.

  This method is thread-safe.

  Parameters:
    `line` - The line
  Since:
    jEdit 4.0pre1

### getLineSegment

    public java.lang.CharSequence getLineSegment(int line)

  Returns the text on the specified line. This method is thread-safe.

  Parameters:
    `line` - The line index.
  Returns:
    The text, or null if the line is invalid
  Since:
    jEdit 4.3pre15

### getText

    public java.lang.String getText(int start,
                                    int length)

  Returns the specified text range. This method is thread-safe.

  Parameters:
    `start` - The start offset
    `length` - The number of characters to get

### getText

    public void getText(int start,
                        int length,
                        javax.swing.text.Segment seg)

  Returns the specified text range in a `Segment`.

  Using a <classname>Segment</classname> is generally more efficient than using a <classname>String</classname> because it results in less memory allocation and array copying.

  This method is thread-safe.

  Parameters:
    `start` - The start offset
    `length` - The number of characters to get
    `seg` - The segment to copy the text to

### getSegment

    public java.lang.CharSequence getSegment(int start,
                                             int length)

  Returns the specified text range. This method is thread-safe.

  Parameters:
    `start` - The start offset
    `length` - The number of characters to get
  Since:
    jEdit 4.3pre15

### insert

    public void insert(int offset,
                       java.lang.String str)

  Inserts a string into the buffer.

  Parameters:
    `offset` - The offset
    `str` - The string
  Since:
    jEdit 4.0pre1

### insert

    public void insert(int offset,
                       javax.swing.text.Segment seg)

  Inserts a string into the buffer.

  Parameters:
    `offset` - The offset
    `seg` - The segment
  Since:
    jEdit 4.0pre1

### remove

    public void remove(int offset,
                       int length)

  Removes the specified rang efrom the buffer.

  Parameters:
    `offset` - The start offset
    `length` - The number of characters to remove

### removeTrailingWhiteSpace

    public void removeTrailingWhiteSpace(int[] lines)

  Removes trailing whitespace from all lines in the specified list.

  Parameters:
    `lines` - The line numbers
  Since:
    jEdit 3.2pre1

### shiftIndentLeft

    public void shiftIndentLeft(int[] lines)

  Shifts the indent of each line in the specified list to the left.

  Parameters:
    `lines` - The line numbers
  Since:
    jEdit 3.2pre1

### shiftIndentRight

    public void shiftIndentRight(int[] lines)

  Shifts the indent of each line in the specified list to the right.

  Parameters:
    `lines` - The line numbers
  Since:
    jEdit 3.2pre1

### indentLines

    public void indentLines(int start,
                            int end)

  Indents all specified lines.

  Parameters:
    `start` - The first line to indent
    `end` - The last line to indent
  Since:
    jEdit 3.1pre3

### indentLines

    public void indentLines(int[] lines)

  Indents all specified lines.

  Parameters:
    `lines` - The line numbers
  Since:
    jEdit 3.2pre1

### indentLine

    @Deprecated
    public boolean indentLine(int lineIndex,
                                         boolean canIncreaseIndent,
                                         boolean canDecreaseIndent)

  Deprecated. Use `indentLine(int,boolean)` instead.

### indentLine

    public boolean indentLine(int lineIndex,
                              boolean canDecreaseIndent)

  Indents the specified line.

  Parameters:
    `lineIndex` - The line number to indent
    `canDecreaseIndent` - If true, the indent can be decreased as a result of this. Set this to false for Tab key.
  Returns:
    true If indentation took place, false otherwise.
  Since:
    jEdit 4.2pre2

### getCurrentIndentForLine

    public int getCurrentIndentForLine(int lineIndex,
                                       int[] whitespaceChars)

  Returns the line's current leading indent.

  Parameters:
    `lineIndex` - The line number
    `whitespaceChars` - If this is non-null, the number of whitespace characters is stored at the 0 index
  Since:
    jEdit 4.2pre2

### getIdealIndentForLine

    public int getIdealIndentForLine(int lineIndex)

  Returns the ideal leading indent for the specified line. This will apply the various auto-indent rules.

  Parameters:
    `lineIndex` - The line number

### getVirtualWidth

    public int getVirtualWidth(int line,
                               int column)

  Returns the virtual column number (taking tabs into account) of the specified position.

  Parameters:
    `line` - The line number
    `column` - The column number
  Since:
    jEdit 4.1pre1

### getOffsetOfVirtualColumn

    public int getOffsetOfVirtualColumn(int line,
                                        int column,
                                        int[] totalVirtualWidth)

  Returns the offset of a virtual column number (taking tabs into account) relative to the start of the line in question.

  Parameters:
    `line` - The line number
    `column` - The virtual column number
    `totalVirtualWidth` - If this array is non-null, the total virtual width will be stored in its first location if this method returns -1.
  Returns:
    -1 if the column is out of bounds
  Since:
    jEdit 4.1pre1

### insertAtColumn

    public void insertAtColumn(int line,
                               int col,
                               java.lang.String str)

  Like the `insert(int,String)` method, but inserts the string at the specified virtual column. Inserts spaces as appropriate if the line is shorter than the column.

  Parameters:
    `line` - The line number
    `col` - The virtual column number
    `str` - The string

### insertIndented

    public int insertIndented(int offset,
                              java.lang.String text)

  Inserts a string into the buffer, indenting each line of the string to match the indent of the first line.

  Parameters:
    `offset` - The offset
    `text` - The text
  Returns:
    The number of characters of indent inserted on each new line. This is used by the abbreviations code.
  Since:
    jEdit 4.2pre14

### isElectricKey

    public boolean isElectricKey(char ch)

  Deprecated. Use #isElectricKey(char,int)

  Should inserting this character trigger a re-indent of the current line?

  Since:
    jEdit 4.3pre2

### isElectricKey

    public boolean isElectricKey(char ch,
                                 int line)

  Should inserting this character trigger a re-indent of the current line?

  Since:
    jEdit 4.3pre9

### markTokens

    public void markTokens(int lineIndex,
                           TokenHandler tokenHandler)

  Returns the syntax tokens for the specified line.

  Parameters:
    `lineIndex` - The line number
    `tokenHandler` - The token handler that will receive the syntax tokens
  Since:
    jEdit 4.1pre1

### getTokenMarker

    public TokenMarker getTokenMarker()

### setTokenMarker

    public void setTokenMarker(TokenMarker tokenMarker)

### createPosition

    public javax.swing.text.Position createPosition(int offset)

  Creates a floating position.

  Parameters:
    `offset` - The offset

### propertiesChanged

    public void propertiesChanged()

  Reloads settings from the properties. This should be called after the `syntax` or `folding` buffer-local properties are changed.

### getTabSize

    public int getTabSize()

  Returns the tab size used in this buffer. This is equivalent to calling `getProperty("tabSize")`. This method is thread-safe.

### getIndentSize

    public int getIndentSize()

  Returns the indent size used in this buffer. This is equivalent to calling `getProperty("indentSize")`. This method is thread-safe.

  Since:
    jEdit 2.7pre1

### getProperty

    public java.lang.Object getProperty(java.lang.Object name)

  Returns the value of a buffer-local property.

  Using this method is generally discouraged, because it returns an `Object` which must be cast to another type in order to be useful, and this can cause problems if the object is of a different type than what the caller expects.

  The following methods should be used instead:

  - `getStringProperty(String)`
  - `getBooleanProperty(String)`
  - `getIntegerProperty(String,int)`
  This method is thread-safe.

  Parameters:
    `name` - The property name. For backwards compatibility, this is an `Object`, not a `String`.

### getDefaultProperty

    public java.lang.Object getDefaultProperty(java.lang.String key)

### setProperty

    public void setProperty(java.lang.String name,
                            java.lang.Object value)

  Sets the value of a buffer-local property.

  Parameters:
    `name` - The property name
    `value` - The property value
  Since:
    jEdit 4.0pre1

### setDefaultProperty

    public void setDefaultProperty(java.lang.String name,
                                   java.lang.Object value)

### unsetProperty

    public void unsetProperty(java.lang.String name)

  Clears the value of a buffer-local property.

  Parameters:
    `name` - The property name
  Since:
    jEdit 4.0pre1

### resetCachedProperties

    public void resetCachedProperties()

### getStringProperty

    public java.lang.String getStringProperty(java.lang.String name)

  Returns the value of a string property. This method is thread-safe.

  Parameters:
    `name` - The property name
  Since:
    jEdit 4.0pre1

### setStringProperty

    public void setStringProperty(java.lang.String name,
                                  java.lang.String value)

  Sets a string property.

  Parameters:
    `name` - The property name
    `value` - The value
  Since:
    jEdit 4.0pre1

### getBooleanProperty

    public boolean getBooleanProperty(java.lang.String name)

  Returns the value of a boolean property. This method is thread-safe.

  Parameters:
    `name` - The property name
  Since:
    jEdit 4.0pre1

### getBooleanProperty

    public boolean getBooleanProperty(java.lang.String name,
                                      boolean def)

  Returns the value of a boolean property. This method is thread-safe.

  Parameters:
    `name` - The property name
    `def` - The default value
  Since:
    jEdit 4.3pre17

### setBooleanProperty

    public void setBooleanProperty(java.lang.String name,
                                   boolean value)

  Sets a boolean property.

  Parameters:
    `name` - The property name
    `value` - The value
  Since:
    jEdit 4.0pre1

### getIntegerProperty

    public int getIntegerProperty(java.lang.String name,
                                  int defaultValue)

  Returns the value of an integer property. This method is thread-safe.

  Parameters:
    `name` - The property name
  Since:
    jEdit 4.0pre1

### setIntegerProperty

    public void setIntegerProperty(java.lang.String name,
                                   int value)

  Sets an integer property.

  Parameters:
    `name` - The property name
    `value` - The value
  Since:
    jEdit 4.0pre1

### getPatternProperty

    public java.util.regex.Pattern getPatternProperty(java.lang.String name,
                                                      int flags)

  Returns the value of a property as a regular expression. This method is thread-safe.

  Parameters:
    `name` - The property name
    `flags` - Regular expression compilation flags
  Since:
    jEdit 4.3pre5

### getRuleSetAtOffset

    public ParserRuleSet getRuleSetAtOffset(int offset)

  Returns the syntax highlighting ruleset at the specified offset.

  Since:
    jEdit 4.1pre1

### getKeywordMapAtOffset

    public KeywordMap getKeywordMapAtOffset(int offset)

  Returns the syntax highlighting keyword map in effect at the specified offset. Used by the Complete Word command to complete keywords.

  Parameters:
    `offset` - The offset
  Since:
    jEdit 4.0pre3

### getContextSensitiveProperty

    public java.lang.String getContextSensitiveProperty(int offset,
                                                        java.lang.String name)

  Some settings, like comment start and end strings, can vary between different parts of a buffer (HTML text and inline JavaScript, for example).

  Parameters:
    `offset` - The offset
    `name` - The property name
  Since:
    jEdit 4.0pre3

### getMode

    public Mode getMode()

  Returns this buffer's edit mode. This method is thread-safe.

### setMode

    public void setMode(java.lang.String mode)

  Sets this buffer's edit mode. Note that calling this before a buffer is loaded will have no effect; in that case, set the "mode" property to the name of the mode. A bit inelegant, I know...

  Parameters:
    `mode` - The mode name
  Since:
    jEdit 4.2pre1

### setMode

    public void setMode(Mode mode)

  Sets this buffer's edit mode. Note that calling this before a buffer is loaded will have no effect; in that case, set the "mode" property to the name of the mode. A bit inelegant, I know...

  Parameters:
    `mode` - The mode

### isFoldStart

    public boolean isFoldStart(int line)

  Returns if the specified line begins a fold.

  Since:
    jEdit 3.1pre1

### isFoldEnd

    public boolean isFoldEnd(int line)

  Returns if the specified line ends a fold.

  Since:
    jEdit 4.2pre5

### invalidateCachedFoldLevels

    public void invalidateCachedFoldLevels()

  Invalidates all cached fold level information.

  Since:
    jEdit 4.1pre11

### getFoldLevel

    public int getFoldLevel(int line)

  Returns the fold level of the specified line.

  Parameters:
    `line` - A physical line index
  Since:
    jEdit 3.1pre1

### getFoldAtLine

    public int[] getFoldAtLine(int line)

  Returns an array. The first element is the start line, the second element is the end line, of the fold containing the specified line number.

  Parameters:
    `line` - The line number
  Since:
    jEdit 4.0pre3

### getFoldHandler

    public FoldHandler getFoldHandler()

  Returns the current buffer's fold handler.

  Since:
    jEdit 4.2pre1

### setFoldHandler

    public void setFoldHandler(FoldHandler foldHandler)

  Sets the buffer's fold handler.

  Since:
    jEdit 4.2pre2

### undo

    public void undo(TextArea textArea)

  Undoes the most recent edit.

  Since:
    jEdit 4.0pre1

### redo

    public void redo(TextArea textArea)

  Redoes the most recently undone edit.

  Since:
    jEdit 2.7pre2

### isTransactionInProgress

    public boolean isTransactionInProgress()

  Returns if an undo or compound edit is currently in progress. If this method returns true, then eventually a `BufferListener.transactionComplete(JEditBuffer)` buffer event will get fired.

  Since:
    jEdit 4.0pre6

### beginCompoundEdit

    public void beginCompoundEdit()

  Starts a compound edit. All edits from now on until `endCompoundEdit()` are called will be merged into one. This can be used to make a complex operation undoable in one step. Nested calls to `beginCompoundEdit()` behave as expected, requiring the same number of `endCompoundEdit()` calls to end the edit.

  See Also:
    `endCompoundEdit()`

### endCompoundEdit

    public void endCompoundEdit()

  Ends a compound edit. All edits performed since `beginCompoundEdit()` was called can now be undone in one step by calling `undo(TextArea)`.

  See Also:
    `beginCompoundEdit()`

### insideCompoundEdit

    public boolean insideCompoundEdit()

  Returns if a compound edit is currently active.

  Since:
    jEdit 3.1pre1

### isUndoInProgress

    public boolean isUndoInProgress()

  Returns if an undo or redo is currently being performed.

  Since:
    jEdit 4.3pre3

### getUndoId

    public java.lang.Object getUndoId()

  Returns an object that identifies the undo operation to which the current content change belongs. This method can be used by buffer listeners during content changes (contentInserted/contentRemoved) to find out which content changes belong to the same "undo" operation. The same undoId object will be returned for all content changes belonging to the same undo operation. Only the identity of the undoId can be used, by comparing it with a previously-returned undoId using "==".

  Since:
    jEdit 4.3pre18

### addBufferListener

    public void addBufferListener(BufferListener listener,
                                  int priority)

  Adds a buffer change listener.

  Parameters:
    `listener` - The listener
    `priority` - Listeners with HIGH_PRIORITY get the event before listeners with NORMAL_PRIORITY
  Since:
    jEdit 4.3pre3

### addBufferListener

    public void addBufferListener(BufferListener listener)

  Adds a buffer change listener.

  Parameters:
    `listener` - The listener
  Since:
    jEdit 4.3pre3

### removeBufferListener

    public void removeBufferListener(BufferListener listener)

  Removes a buffer change listener.

  Parameters:
    `listener` - The listener
  Since:
    jEdit 4.3pre3

### getBufferListeners

    public BufferListener[] getBufferListeners()

  Returns an array of registered buffer change listeners.

  Since:
    jEdit 4.3pre3

### setUndoLimit

    public void setUndoLimit(int limit)

  Set the undo limit of the Undo Manager.

  Parameters:
    `limit` - the new limit
  Since:
    jEdit 4.3pre16

### canUndo

    public boolean canUndo()

  Returns true if an undo operation can be performed.

  Since:
    jEdit 4.3pre18

### canRedo

    public boolean canRedo()

  Returns true if a redo operation can be performed.

  Since:
    jEdit 4.3pre18

### fireFoldLevelChanged

    protected void fireFoldLevelChanged(int start,
                                        int end)

### fireContentInserted

    protected void fireContentInserted(int startLine,
                                       int offset,
                                       int numLines,
                                       int length)

### fireContentRemoved

    protected void fireContentRemoved(int startLine,
                                      int offset,
                                      int numLines,
                                      int length)

### firePreContentInserted

    protected void firePreContentInserted(int startLine,
                                          int offset,
                                          int numLines,
                                          int length)

### firePreContentRemoved

    protected void firePreContentRemoved(int startLine,
                                         int offset,
                                         int numLines,
                                         int length)

### fireBeginUndo

    protected void fireBeginUndo()

### fireEndUndo

    protected void fireEndUndo()

### fireBeginRedo

    protected void fireBeginRedo()

### fireEndRedo

    protected void fireEndRedo()

### fireTransactionComplete

    protected void fireTransactionComplete()

### fireFoldHandlerChanged

    protected void fireFoldHandlerChanged()

### fireBufferLoaded

    protected void fireBufferLoaded()

### isFileReadOnly

    protected boolean isFileReadOnly()

### setFileReadOnly

    protected void setFileReadOnly(boolean readOnly)

### loadText

    protected void loadText(javax.swing.text.Segment seg,
                            IntegerArray endOffsets)

### invalidateFoldLevels

    protected void invalidateFoldLevels()

### parseBufferLocalProperties

    protected void parseBufferLocalProperties()