Class Fold

  • All Implemented Interfaces:
    Comparable<Fold>

    public class Fold
    extends Object
    implements Comparable<Fold>
    Information about a foldable region.

    A Fold has zero or more children, and Folds thus form a hierarchical structure, with "parent" folds containing the info about any "child" folds they contain.

    Fold regions are denoted by a starting and ending offset, but the actual folding is done on a per-line basis, so Fold instances provide methods for retrieving both starting and ending offsets and lines. The starting and ending offsets/lines are "sticky" and correctly track their positions even as the document is modified.

    • Method Detail

      • createChild

        public Fold createChild​(int type,
                                int startOffs)
                         throws BadLocationException
        Creates a fold that is a child of this one.
        Parameters:
        type - The type of fold.
        startOffs - The starting offset of the fold.
        Returns:
        The child fold.
        Throws:
        BadLocationException - If startOffs is invalid.
        See Also:
        FoldType
      • compareTo

        public int compareTo​(Fold otherFold)
        Two folds are considered equal if they start at the same offset.
        Specified by:
        compareTo in interface Comparable<Fold>
        Parameters:
        otherFold - Another fold to compare this one to.
        Returns:
        How this fold compares to the other.
      • containsLine

        public boolean containsLine​(int line)
        Returns whether the specified line would be hidden in this fold. Since RSTA displays the "first" line in a fold, this means that the line must must be between (getStartLine()+1) and getEndLine(), inclusive.
        Parameters:
        line - The line to check.
        Returns:
        Whether the line would be hidden if this fold is collapsed.
        See Also:
        containsOffset(int), containsOrStartsOnLine(int)
      • containsOrStartsOnLine

        public boolean containsOrStartsOnLine​(int line)
        Returns whether the given line is in the range [getStartLine(), getEndLine()], inclusive.
        Parameters:
        line - The line to check.
        Returns:
        Whether this fold contains, or starts on, the line.
        See Also:
        containsLine(int)
      • containsOffset

        public boolean containsOffset​(int offs)
        Returns whether the specified offset is "inside" the fold. This method returns true if the offset is greater than the fold start offset, and no further than the last offset of the last folded line.
        Parameters:
        offs - The offset to check.
        Returns:
        Whether the offset is "inside" the fold.
        See Also:
        containsLine(int)
      • equals

        public boolean equals​(Object otherFold)
        Two folds are considered equal if they have the same starting offset.
        Overrides:
        equals in class Object
        Parameters:
        otherFold - Another fold to compare this one to.
        Returns:
        Whether the two folds are equal.
        See Also:
        compareTo(Fold)
      • getChild

        public Fold getChild​(int index)
        Returns a specific child fold.
        Parameters:
        index - The index of the child fold.
        Returns:
        The child fold.
        See Also:
        getChildCount()
      • getChildCount

        public int getChildCount()
        Returns the number of child folds.
        Returns:
        The number of child folds.
        See Also:
        getChild(int)
      • getCollapsedLineCount

        public int getCollapsedLineCount()
        Returns the number of collapsed lines under this fold. If this fold is collapsed, this method returns getLineCount(), otherwise it returns the sum of all collapsed lines of all child folds of this one.

        The value returned is cached, so this method returns quickly and shouldn't affect performance.

        Returns:
        The number of collapsed lines under this fold.
      • getEndLine

        public int getEndLine()
        Returns the end line of this fold. For example, in languages such as C and Java, this might be the line containing the closing curly brace of a code block.

        The value returned by this method will automatically update as the text area's contents are modified, to track the ending line of the code block.

        Returns:
        The end line of this code block.
        See Also:
        getEndOffset(), getStartLine()
      • getEndOffset

        public int getEndOffset()
        Returns the end offset of this fold. For example, in languages such as C and Java, this might be the offset of the closing curly brace of a code block.

        The value returned by this method will automatically update as the text area's contents are modified, to track the ending offset of the code block.

        Returns:
        The end offset of this code block, or Integer.MAX_VALUE if this fold region isn't closed properly. The latter causes this fold to collapsed all lines through the end of the file.
        See Also:
        getEndLine(), getStartOffset()
      • getFoldType

        public int getFoldType()
        Returns the type of fold this is. This will be one of the values in FoldType, or a user-defined value.
        Returns:
        The type of fold this is.
      • getHasChildFolds

        public boolean getHasChildFolds()
        Returns whether this fold has any child folds.
        Returns:
        Whether this fold has any children.
        See Also:
        getChildCount()
      • getLastChild

        public Fold getLastChild()
        Returns the last child fold.
        Returns:
        The last child fold, or null if this fold does not have any children.
        See Also:
        getChild(int), getHasChildFolds()
      • getLineCount

        public int getLineCount()
        Returns the number of lines that are hidden when this fold is collapsed.
        Returns:
        The number of lines hidden.
        See Also:
        getStartLine(), getEndLine()
      • getParent

        public Fold getParent()
        Returns the parent fold of this one.
        Returns:
        The parent fold, or null if this is a top-level fold.
      • getStartLine

        public int getStartLine()
        Returns the starting line of this fold region. This is the only line in the fold region that is not hidden when a fold is collapsed.

        The value returned by this method will automatically update as the text area's contents are modified, to track the starting line of the code block.

        Returns:
        The starting line of the code block.
        See Also:
        getEndLine(), getStartOffset()
      • getStartOffset

        public int getStartOffset()
        Returns the starting offset of this fold region. For example, for languages such as C and Java, this would be the offset of the opening curly brace of a code block.

        The value returned by this method will automatically update as the text area's contents are modified, to track the starting offset of the code block.

        Returns:
        The start offset of this fold.
        See Also:
        getStartLine(), getEndOffset()
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class Object
      • isOnSingleLine

        public boolean isOnSingleLine()
        Returns whether this fold is entirely on a single line. In general, a FoldParser should not remember fold regions all on a single line, since there's really nothing to fold.
        Returns:
        Whether this fold is on a single line.
        See Also:
        removeFromParent()
      • removeFromParent

        public boolean removeFromParent()
        Removes this fold from its parent. This should only be called by FoldParser implementations if they determine that a fold is all on a single line (and thus shouldn't be remembered) after creating it.
        Returns:
        Whether this fold had a parent to be removed from.
        See Also:
        isOnSingleLine()
      • setCollapsed

        public void setCollapsed​(boolean collapsed)
        Sets whether this Fold is collapsed. Calling this method will update both the text area and all Gutter components.
        Parameters:
        collapsed - Whether this fold should be collapsed.
        See Also:
        isCollapsed(), toggleCollapsedState()
      • setEndOffset

        public void setEndOffset​(int endOffs)
                          throws BadLocationException
        Sets the ending offset of this fold, such as the closing curly brace of a code block in C or Java. FoldParser implementations should call this on an existing Fold upon finding its end. If this method isn't called, then this Fold is considered to have no end, i.e., it will collapse everything to the end of the file.
        Parameters:
        endOffs - The end offset of this fold.
        Throws:
        BadLocationException - If endOffs is not a valid location in the text area.
      • toggleCollapsedState

        public void toggleCollapsedState()
        Toggles the collapsed state of this fold.
        See Also:
        setCollapsed(boolean)
      • toString

        public String toString()
        Overridden for debugging purposes.
        Overrides:
        toString in class Object
        Returns:
        A string representation of this Fold.