org.apache.fop.layoutmgr

Class KnuthPenalty

java.lang.Object

org.apache.fop.layoutmgr.ListElement

org.apache.fop.layoutmgr.KnuthElement

org.apache.fop.layoutmgr.KnuthPenalty

Direct Known Subclasses:

WhitespaceManagementPenalty

public class KnuthPenalty
extends KnuthElement

An instance of this class represents information about a feasible breaking point; it does not represent any piece of content. A KnuthPenalty is a feasible breaking point unless its value is infinity; a KnuthPenalty whose value is -infinity represents a forced break. A KnuthPenalty is suppressed, and its width is ignored, if it is not a chosen breaking point; for example, a KnuthPenalty representing a hyphenation point has a width (the "-" width), which must be ignored if that point is not chosen as a breaking point. Besides the inherited methods and attributes, this class has two more attributes and the methods used to get them: the penalty value, which is a kind of "aesthetic cost" (the higher the value, the more unsightly the breaking point), and a boolean that marks KnuthPenalties which should not be chosen as breaking points for consecutive lines.

Field Summary

Fields

Modifier and Type	Field and Description
static KnuthPenalty	DUMMY_ZERO_PENALTY Dummy, zero-width penalty
static int	FLAGGED_PENALTY Used for flagged penalties.

Fields inherited from class org.apache.fop.layoutmgr.KnuthElement

INFINITE

Constructor Summary

Constructors

Constructor and Description
KnuthPenalty(int width, int penalty, boolean penaltyFlagged, int breakClass, Position pos, boolean isAuxiliary) Create a new KnuthPenalty.
KnuthPenalty(int width, int penalty, boolean penaltyFlagged, Position pos, boolean auxiliary) Create a new KnuthPenalty.

Method Summary

Modifier and Type	Method and Description
int	getBreakClass()
int	getPenalty()
boolean	isForcedBreak()
boolean	isPenalty()
boolean	isPenaltyFlagged()
void	setPenalty(int penalty) Sets a new penalty value.
String	toString()
protected static String	valueOf(int penaltyValue) Get the penalty's value as a String.

Methods inherited from class org.apache.fop.layoutmgr.KnuthElement

getShrink, getStretch, getWidth, isAuxiliary, isUnresolvedElement

Methods inherited from class org.apache.fop.layoutmgr.ListElement

getLayoutManager, getPosition, isBox, isGlue, setPosition

Methods inherited from class java.lang.Object

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

Field Detail

FLAGGED_PENALTY

public static final int FLAGGED_PENALTY

Used for flagged penalties. See Knuth algorithm.

See Also:

Constant Field Values

DUMMY_ZERO_PENALTY

public static final KnuthPenalty DUMMY_ZERO_PENALTY

Dummy, zero-width penalty

Constructor Detail

KnuthPenalty

public KnuthPenalty(int width,
                    int penalty,
                    boolean penaltyFlagged,
                    Position pos,
                    boolean auxiliary)

Create a new KnuthPenalty.

Parameters:

width - the width of this penalty

penalty - the penalty value of this penalty

penaltyFlagged - is this penalty flagged?

pos - the Position stored in this penalty

auxiliary - is this penalty auxiliary?

KnuthPenalty

public KnuthPenalty(int width,
                    int penalty,
                    boolean penaltyFlagged,
                    int breakClass,
                    Position pos,
                    boolean isAuxiliary)

Create a new KnuthPenalty.

Parameters:

width - the width of this penalty

penalty - the penalty value of this penalty

penaltyFlagged - is this penalty flagged?

breakClass - the break class of this penalty (one of Constants.EN_AUTO, Constants.EN_COLUMN, Constants.EN_PAGE, Constants.EN_EVEN_PAGE, Constants.EN_ODD_PAGE).

pos - the Position stored in this penalty

isAuxiliary - is this penalty auxiliary?

Method Detail

valueOf

protected static String valueOf(int penaltyValue)

Get the penalty's value as a String. (Mainly used in toString() methods, to improve readability of the trace logs.) TODO: shouldn't be penalty a class of its own?

Parameters:

penaltyValue - the penalty value

Returns:

the penalty value as a String

isPenalty

public boolean isPenalty()

Overrides:

isPenalty in class ListElement

Returns:

true if this element is a KnuthPenalty.

getPenalty

public int getPenalty()

Overrides:

getPenalty in class KnuthElement

Returns:

the penalty value of this penalty.

setPenalty

public void setPenalty(int penalty)

Sets a new penalty value.

Parameters:

penalty - the new penalty value

isPenaltyFlagged

public boolean isPenaltyFlagged()

Returns:

true is this penalty is a flagged one.

isForcedBreak

public boolean isForcedBreak()

Overrides:

isForcedBreak in class ListElement

Returns:

true if the element is a penalty and represents a forced break.

getBreakClass

public int getBreakClass()

Returns:

the break class of this penalty (EN_AUTO, EN_COLUMN, EN_PAGE, EN_EVEN_PAGE, EN_ODD_PAGE)

toString

public String toString()

Overrides:

toString in class Object