IltLinkLayout (ILOG JViews TGO 8.1 API)

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ilog.tgo.graphic.graphlayout
Class IltLinkLayout

java.lang.Object
  ilog.views.graphlayout.IlvGraphLayout
      ilog.tgo.graphic.graphlayout.IltLinkLayout

All Implemented Interfaces:: GraphModelListener, Serializable, EventListener

public class IltLinkLayout
extends IlvGraphLayout
extends IlvGraphLayout

This is an extended version of the ILOG JViews IlvLinkLayout class. When in short link layout mode, it allows the specification of link connection ports on on every node, and of a set of allowed link connection ports for every link end. It uses an IltShortLinkLayout instance as short link layout.

The Link Layout algorithm reshapes the links of a graph without moving the nodes. By default, the algorithm computes orthogonal links (that is, links composed of alternating horizontal and vertical segments). Optionally, direct links can be computed. See the method setGlobalLinkStyle(int).

The layout algorithm has two modes: short link mode and long link mode. The short link mode places the links freely in the plane by choosing the best shape from a fixed number of link shapes. A link has a maximum of 3 bends. The long link mode searches for routes on a grid by avoiding obstacles. By doing this, any link shape can occur (that is, the number of link shapes is unlimited) but a long link route can have many bends.

The long link mode is slower and uses more memory on very large graphs than the short link mode. The short link mode should be used if any of the following conditions apply:

Most of the links are short and it is not fatal if long links overlap obstacles.
The link routes must be placed freely and cannot be restricted to a grid.
It is important to limit the number of bends.
Maximal speed and minimal memory usage are important on huge graphs.

The long link mode should be used if any of the following conditions apply:

Many links are long and it is important that long orthogonal links do not overlap obstacles.
Routing on a grid is preferred because it guarantees a minimal distance between link segments.
An increasing number of bends is acceptable if this avoids any overlaps. The long link mode can be used to find an orthogonal route without overlaps in a labyrinth of node obstacles.

Here are sample drawings produced by the Link Layout algorithm:

Click on the image to see it in normal size.

The short link mode works very well with thick links produced by Java 2D:

Click on the image to see it in normal size.

Here are sample drawings produced by the Link Layout algorithm in long link mode:

Click on the image to see it in normal size.

The long link mode can be used to find a route through a labyrinth:

Click on the image to see it in normal size.

The Link Layout algorithm is a wrapper that allows simplified access to two sublayouts: the Short Link Layout algorithm and the Long Link Layout algorithm. It calls these sublayouts internally to perform the layout. This is useful for applications that need to use both layout modes at the same time. Applications that use the short link mode exclusively can use the Short Link Layout algorithm (IltShortLinkLayout) directly. Applications that use the long link mode exclusively can use the Long Link Layout algorithm (IlvLongLinkLayout) directly.

See the corresponding chapter of the User's Manual for details on the algorithm, the types of graphs for which this algorithm can be used, the features and limitations, code samples, and so on.

Note the following points:

The algorithm never moves any nodes. It only reshapes links.
The algorithm normally routes normal links. It has a special mode to route the intergraph links of the graph model.
The algorithm has an incremental mode and a nonincremental mode. In nonincremental mode, the initial shape of the links (at the moment you start the layout) does not affect the resulting layout. However, links specified as fixed while setPreserveFixedLinks(boolean) is enabled, or links that have the link style NO_RESHAPE_STYLE, are not reshaped. The incremental mode cannot be used for intergraph links.
In incremental mode, the initial shape of the link does affect the resulting layout. The algorithm tries to preserve the shape of links that already fit the layout situation.
The algorithm supports self-links and multiple links between the same pair of nodes.

Since:: JViews 3.5., JTGO 2.6
See Also:: Serialized Form

Field Summary
`static int`	`DIRECT_STYLE` Direct link style option.
`static int`	`LONG_LINKS` Long links layout mode.
`static int`	`MIXED_STYLE` Mixed link style option.
`static int`	`NO_RESHAPE_STYLE` No reshape link style option.
`static int`	`ORTHOGONAL_STYLE` Orthogonal link style option.
`static int`	`SHORT_LINKS` Short links layout mode.

Fields inherited from class ilog.views.graphlayout.IlvGraphLayout
`INVERSE_VIEW_COORDINATES, MANAGER_COORDINATES, VIEW_COORDINATES`

Constructor Summary
`IltLinkLayout()` Creates a new instance of the Link Layout algorithm.
`IltLinkLayout(IltLinkLayout source)` Creates a new layout instance by copying an existing one.

Method Summary
`void`	`attach(IlvGraphModel graphModel)` Allows you to specify the graph model you want to lay out.
`int`	`checkAppropriateLink(Object link)` Checks whether the input link is appropriate for this layout.
`void`	`checkAppropriateLinks()` Throws an exception if the links are not appropriate for the layout.
`void`	`contentsChanged(GraphModelEvent event)` Overridden version of the base class method to allow the layout to be automatically restarted each time the layout instance is notified that the structure or the geometry of the graph has changed.
`IlvGraphLayout`	`copy()` Copies the layout instance.
`void`	`copyParameters(IlvGraphLayout source)` Copies the parameters from a given layout instance.
`protected IlvGraphLayoutGrapherProperty`	`createLayoutGrapherProperty(String name, boolean withDefaults)` Returns a new instance of `IltLinkLayoutGrapherProperty` that stores the parameter settings of this layout class.
`protected IlvGraphLayoutLinkProperty`	`createLayoutLinkProperty(String name, IlvGraphic link, boolean withDefaults)` Returns a new instance of `IltLinkLayoutLinkProperty` that stores the parameter settings of this layout class for links.
`void`	`detach()` Detaches the graph model from the layout instance.
`int`	`getGlobalLinkStyle()` Returns the global style of the shapes of links.
`float`	`getHorizontalGridBase()` Returns the horizontal base coordinate of the grid.
`float`	`getHorizontalGridOffset()` Returns the horizontal offset between the grid lines.
`float`	`getHorizontalMinOffset()` Returns the minimal horizontal offset between the node border and a link segment that is (vertically) parallel to the node border.
`int`	`getLayoutMode()` Returns the current layout mode.
`float`	`getLinkOffset()` Returns the offset between links connected on the same side of the node.
`int`	`getLinkStyle(Object link)` Returns the shape style of an individual link.
`IlvLongLinkLayout`	`getLongLinkLayout()` Returns the Long Link Layout instance that is used internally by this Link Layout instance in layout mode `LONG_LINKS`.
`float`	`getMinFinalSegmentLength()` Returns the minimum length of the first and last segments of each link.
`float`	`getMinNodeCornerOffset()` Returns the minimum offset between a node corner and a link starting at this node.
`IlvNodeBoxInterface`	`getNodeBoxInterface()` Returns the node box interface used during the layout, or `null` if none is specified.
`IltNodeSideFilter`	`getNodeSideFilter()` Returns the node-side filter used during layout, or `null` if none is specified.
`IltShortLinkLayout`	`getShortLinkLayout()` Returns the Short Link Layout instance that is used internally by this Link Layout instance in layout mode `SHORT_LINKS`.
`float`	`getVerticalGridBase()` Returns the vertical base coordinate of the grid.
`float`	`getVerticalGridOffset()` Returns the vertical offset between the grid lines.
`float`	`getVerticalMinOffset()` Returns the minimal vertical offset between the node border and a link segment that is (horizontally) parallel to the node border.
`protected void`	`init()` Initializes instance variables.
`boolean`	`isCombinedInterGraphLinksMode()` Returns `true` if the routing of normal links in addition to intergraph links is enabled.
`boolean`	`isGeometryUpToDate()` Returns `false` if at least one node, link, label or obstacle was moved or reshaped since the last time the layout was successfully performed on the same graph or if the layout has never been performed successfully on the same graph.
`boolean`	`isIncrementalMode()` Returns `true` if the incremental mode is enabled.
`boolean`	`isInterGraphLinksMode()` Returns `true` if the routing of intergraph links is enabled.
`boolean`	`isParametersUpToDate()` Returns `false` if at least one parameter was modified since the last time the layout was successfully performed on the same graph or if the layout has never been performed successfully on the same graph.
`boolean`	`isStructureUpToDate()` Returns `false` if at least one modification occurred in the structure of the graph since the last time the layout was successfully performed on the same graph or if the layout has never been performed successfully on the same graph.
`protected void`	`layout(boolean redraw)` Computes the layout using the Link Layout algorithm.
`void`	`markForIncremental(Object link)` Marks the input link to be rerouted with the next call of `performLayout` if incremental mode is enabled.
`protected void`	`performAutoLayout()` Performs the layout again following a structural or a geometric change of the graph.
`void`	`setAllowedTime(long time)` Sets an upper limit for the duration of the layout algorithm.
`void`	`setAnimate(boolean option)` Enables the animation mechanism.
`void`	`setAutoLayout(boolean enable)` Enables the auto layout mode.
`void`	`setCombinedInterGraphLinksMode(boolean enable)` Enables the routing of normal links in addition to intergraph links.
`void`	`setCoordinatesMode(int mode)` Sets the coordinates mode.
`void`	`setGeometryUpToDate(boolean uptodate)` This method is normally called with a `false` argument if the geometry of the graph changed.
`void`	`setGlobalLinkStyle(int style)` Sets the global style of the shapes of links.
`void`	`setGraphModel(IlvGraphModel graphModel)` Sets the graph model to be laid out.
`void`	`setHorizontalGridBase(float coordinate)` Sets the horizontal base coordinate of the grid.
`void`	`setHorizontalGridOffset(float offset)` Sets the horizontal offset between the grid lines.
`void`	`setHorizontalMinOffset(float offset)` Sets the minimal horizontal offset between the node border and a link segment that is (vertically) parallel to the node border.
`void`	`setIncrementalMode(boolean enable)` Enables the incremental layout mode.
`void`	`setInputCheckEnabled(boolean enable)` Enables the checks for the nodes and/or links provided as arguments for the different methods of this layout algorithm.
`void`	`setInterGraphLinksMode(boolean enable)` Enables the routing of intergraph links.
`void`	`setLayoutMode(int mode)` Sets the layout mode.
`void`	`setLinkConnectionBoxInterface(IlvLinkConnectionBoxInterface connectionBoxInterface)` Allows you to specify a link connection box interface for the connection points of links.
`void`	`setLinkOffset(float offset)` Sets the offset between links connected on the same side of the node.
`void`	`setLinkStyle(Object link, int style)` Sets the shape style of an individual link.
`void`	`setMinBusyTime(long time)` Sets the minimal time that the layout algorithm can be busy between two calls of `layoutStepPerformed` when the method `callLayoutStepPerformedIfNeeded` is used.
`void`	`setMinFinalSegmentLength(float length)` Sets the minimum length of the first and last segments of each link.
`void`	`setMinNodeCornerOffset(float offset)` Sets the minimum offset between a node corner and a link starting at this node.
`void`	`setNodeBoxInterface(IlvNodeBoxInterface nodeBoxInterface)` Allows you to specify a node box interface for the obstacle area.
`void`	`setNodeSideFilter(IltNodeSideFilter filter)` Allows you to install a node-side filter, that is, an object that allows or prohibits the connection of the links on a given side of the nodes.
`void`	`setParametersUpToDate(boolean uptodate)` This method is automatically called with a `false` argument each time the value of a parameter is changed.
`void`	`setPreserveFixedLinks(boolean option)` If the argument is `true`, specifies that the layout is not allowed to reshape the links indicated as fixed by the user.
`void`	`setStructureUpToDate(boolean uptodate)` This method is normally called with a `false` argument if the structure of the graph changed.
`void`	`setUseDefaultParameters(boolean option)` If the argument is `true`, specifies that the layout use the default values of all the parameters; that is, the "get..." and "is..." methods return the default values.
`void`	`setVerticalGridBase(float coordinate)` Sets the vertical base coordinate of the grid.
`void`	`setVerticalGridOffset(float offset)` Sets the vertical offset between the grid lines.
`void`	`setVerticalMinOffset(float offset)` Sets the minimal vertical offset between the node border and a link segment that is (horizontally) parallel to the node border.
`boolean`	`stopImmediately()` Stops the running layout algorithm as soon as possible.
`boolean`	`supportsAllowedTime()` Indicates that this layout class can stop the layout computation in a proper manner when the user-defined allowed time is exceeded.
`boolean`	`supportsAnimation()` Indicates that this layout class supports the animation mechanism; that is, it can perform redraws to animate the layout process in some way.
`boolean`	`supportsLinkConnectionBox()` Indicates that this layout class can use a link connection box interface to calculate the end points of a link.
`boolean`	`supportsPreserveFixedLinks()` Indicates that this layout class allows the user to specify fixed links.
`boolean`	`supportsSaveParametersToNamedProperties()` Indicates that this layout class can transfer the layout parameters to named properties.
`boolean`	`supportsStopImmediately()` Indicates that this layout class can interrupt the current run of the layout immediately in a controlled way.

Methods inherited from class ilog.views.graphlayout.IlvGraphLayout
addGraphLayoutEventListener, addGraphLayoutParameterEventListener, afterLayoutOfSubgraph, attach, beforeLayout, beforeLayoutOfSubgraph, callLayoutStepPerformedIfNeeded, cleanGraphModel, cleanLink, cleanNode, clipAllLinks, clipLink, createLayoutNodeProperty, createLayoutReport, getAllowedTime, getAutoLayoutHandler, getBalanceSplineCurveThreshold, getCalcLayoutRegion, getCoordinatesMode, getGrapher, getGraphModel, getInstanceId, getLayout, getLayoutOfConnectedComponents, getLayoutOfConnectedComponentsReport, getLayoutRegion, getLayoutReport, getLayouts, getLinkClipInterface, getLinkConnectionBoxInterface, getMaxSplineCurveSize, getMinBusyTime, getMinSplineCurveSize, getMovingNodes, getParentLayout, getProperty, getProperty, getRecursiveLayout, getRemainingAllowedTime, getSeedValueForRandomGenerator, getSpecLayoutRegion, getSplineLinkFilter, increasePercentageComplete, isAnimate, isAutoLayout, isFitToView, isFixed, isInputCheckEnabled, isLayoutNeeded, isLayoutOfConnectedComponentsEnabled, isLayoutOfConnectedComponentsEnabledByDefault, isLayoutRunning, isLayoutTimeElapsed, isMemorySavings, isPreserveFixedLinks, isPreserveFixedNodes, isSplineRoutingEnabled, isStoppedImmediately, isUseDefaultParameters, isUseSeedValueForRandomGenerator, layoutStepPerformed, onParameterChanged, onParameterChanged, performLayout, performLayout, performLayout, PerformLayout, performSublayout, removeGraphLayoutEventListener, removeGraphLayoutParameterEventListener, setAutoLayoutHandler, setBalanceSplineCurveThreshold, setFixed, setGrapher, setLayoutOfConnectedComponents, setLayoutOfConnectedComponentsEnabled, setLayoutRegion, setLayoutRegion, setLayoutRegion, setLayoutReport, setLinkClipInterface, setMaxSplineCurveSize, setMemorySavings, setMinSplineCurveSize, setParentLayout, setPreserveFixedNodes, setProperty, setProperty, setSeedValueForRandomGenerator, setSplineLinkFilter, setSplineRoutingEnabled, setUseSeedValueForRandomGenerator, supportsLayoutOfConnectedComponents, supportsLayoutRegion, supportsLinkClipping, supportsMemorySavings, supportsPercentageComplete, supportsPreserveFixedNodes, supportsRandomGenerator, supportsSplineRouting, unfixAllLinks, unfixAllNodes, useAnimateRedraw

Methods inherited from class ilog.views.graphlayout.IlvGraphLayout

addGraphLayoutEventListener, addGraphLayoutParameterEventListener, afterLayoutOfSubgraph, attach, beforeLayout, beforeLayoutOfSubgraph, callLayoutStepPerformedIfNeeded, cleanGraphModel, cleanLink, cleanNode, clipAllLinks, clipLink, createLayoutNodeProperty, createLayoutReport, getAllowedTime, getAutoLayoutHandler, getBalanceSplineCurveThreshold, getCalcLayoutRegion, getCoordinatesMode, getGrapher, getGraphModel, getInstanceId, getLayout, getLayoutOfConnectedComponents, getLayoutOfConnectedComponentsReport, getLayoutRegion, getLayoutReport, getLayouts, getLinkClipInterface, getLinkConnectionBoxInterface, getMaxSplineCurveSize, getMinBusyTime, getMinSplineCurveSize, getMovingNodes, getParentLayout, getProperty, getProperty, getRecursiveLayout, getRemainingAllowedTime, getSeedValueForRandomGenerator, getSpecLayoutRegion, getSplineLinkFilter, increasePercentageComplete, isAnimate, isAutoLayout, isFitToView, isFixed, isInputCheckEnabled, isLayoutNeeded, isLayoutOfConnectedComponentsEnabled, isLayoutOfConnectedComponentsEnabledByDefault, isLayoutRunning, isLayoutTimeElapsed, isMemorySavings, isPreserveFixedLinks, isPreserveFixedNodes, isSplineRoutingEnabled, isStoppedImmediately, isUseDefaultParameters, isUseSeedValueForRandomGenerator, layoutStepPerformed, onParameterChanged, onParameterChanged, performLayout, performLayout, performLayout, PerformLayout, performSublayout, removeGraphLayoutEventListener, removeGraphLayoutParameterEventListener, setAutoLayoutHandler, setBalanceSplineCurveThreshold, setFixed, setGrapher, setLayoutOfConnectedComponents, setLayoutOfConnectedComponentsEnabled, setLayoutRegion, setLayoutRegion, setLayoutRegion, setLayoutReport, setLinkClipInterface, setMaxSplineCurveSize, setMemorySavings, setMinSplineCurveSize, setParentLayout, setPreserveFixedNodes, setProperty, setProperty, setSeedValueForRandomGenerator, setSplineLinkFilter, setSplineRoutingEnabled, setUseSeedValueForRandomGenerator, supportsLayoutOfConnectedComponents, supportsLayoutRegion, supportsLinkClipping, supportsMemorySavings, supportsPercentageComplete, supportsPreserveFixedNodes, supportsRandomGenerator, supportsSplineRouting, unfixAllLinks, unfixAllNodes, useAnimateRedraw

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

Field Detail

ORTHOGONAL_STYLE

public static final int ORTHOGONAL_STYLE

Orthogonal link style option. When used as the argument of the method setGlobalLinkStyle(int), all links have an orthogonal shape (alternating horizontal and vertical segments). To specify the style of an individual link, use this option as the argument of the method setLinkStyle(Object, int).

See Also:: Constant Field Values

DIRECT_STYLE

public static final int DIRECT_STYLE

Direct link style option. When used as the argument of the method setGlobalLinkStyle(int), all links have a (semi)direct shape. To specify the style of an individual link, use this option as the argument of the method setLinkStyle(Object, int).

See Also:: Constant Field Values

MIXED_STYLE

public static final int MIXED_STYLE

Mixed link style option. When used as the argument of the method setGlobalLinkStyle(int), each link can have a different shape. The shape of an individual link can be set by the method setLinkStyle(java.lang.Object, int).

See Also:: Constant Field Values

NO_RESHAPE_STYLE

public static final int NO_RESHAPE_STYLE

No reshape link style option. This can be used for individual links if the global link style is MIXED_STYLE. To specify the style of an individual link, use this option as the argument of the method setLinkStyle(Object, int).

See Also:: Constant Field Values

SHORT_LINKS

public static final int SHORT_LINKS

Short links layout mode. When used as the argument of the method setLayoutMode(int), links are placed freely in the plane by choosing the best shape from a fixed number of link shapes. A link can have a maximum of 3 bends.

See Also:: Constant Field Values

LONG_LINKS

public static final int LONG_LINKS

Long links layout mode.

When used as the argument of the method setLayoutMode(int), links of link style ORTHOGONAL_STYLE are routed on a grid and avoid obstacles. By so doing, any orthogonal link shape can occur (that is, the number of link shapes is unlimited) and a long link route can have many bends.

Links of link style DIRECT_STYLE are routed with the end segments on the grid, but the middle segment may overlap obstacles.

See Also:: Constant Field Values

Constructor Detail

IltLinkLayout

public IltLinkLayout()

Creates a new instance of the Link Layout algorithm.
To indicate the grapher you want to lay out, use the method IlvGraphLayout.attach(ilog.views.IlvGrapher).
To indicate the graph model you want to lay out, use the method attach(ilog.views.graphlayout.IlvGraphModel).
To perform the layout, use the method IlvGraphLayout.performLayout().
To modify the layout parameters, use the different methods provided in this class and its superclass.

See Also:: IlvGraphLayout.attach(ilog.views.IlvGrapher), IlvGraphLayout.attach(ilog.views.graphlayout.IlvGraphModel), IlvGraphLayout.performLayout(), IlvGrapherAdapter.addLayer(ilog.views.IlvManagerLayer), IlvGrapherAdapter.setFilter(ilog.views.graphlayout.IlvLayoutGraphicFilter)

IltLinkLayout

public IltLinkLayout(IltLinkLayout source)

Creates a new layout instance by copying an existing one. This constructor is used by the copy() method. Any subclass should provide a copy constructor.

The parameters of the source layout are copied using the method copyParameters(ilog.views.graphlayout.IlvGraphLayout).

Parameters:: source - The layout instance that is copied.
Since:: JViews 5.0
See Also:: copy(), copyParameters(ilog.views.graphlayout.IlvGraphLayout)

Method Detail

init

protected void init()

Initializes instance variables.

You should not call this method directly. The method is called internally by the constructor without arguments and by the copy constructor. The method must be overridden by subclasses that need to initialize additional instance variables.

Overrides:: init in class IlvGraphLayout

Since:: JViews 5.0

copy

public IlvGraphLayout copy()

Copies the layout instance.

This method copies the layout instance by calling the copy constructor.

When performing a recursive layout on a nested graph, IlvLayoutProvider uses this method to "clone" the layout instance of a parent graph. Note that the parameters which are specific to a node or a link are not copied. Only the global parameters are copied. The customization interfaces (node side filter, node box interface) are also copied.

Specified by:: copy in class IlvGraphLayout

Returns:: A copy of the layout instance.
Since:: JViews 5.0
See Also:: copyParameters(ilog.views.graphlayout.IlvGraphLayout), setNodeBoxInterface(ilog.views.graphlayout.IlvNodeBoxInterface), setNodeSideFilter(ilog.tgo.graphic.graphlayout.IltNodeSideFilter)

copyParameters

public void copyParameters(IlvGraphLayout source)

Copies the parameters from a given layout instance.

Note that the parameters which are specific to a node or a link are not copied. Only the global parameters are copied. The customization interfaces (node side filter, node box interface) are also copied.

Overrides:: copyParameters in class IlvGraphLayout

Parameters:: source - The layout instance from which the parameters are copied.
Since:: JViews 5.0
See Also:: copy(), setNodeBoxInterface(ilog.views.graphlayout.IlvNodeBoxInterface), setNodeSideFilter(ilog.tgo.graphic.graphlayout.IltNodeSideFilter)

attach

public void attach(IlvGraphModel graphModel)

Allows you to specify the graph model you want to lay out. In addition to the functionality in the base class, the Link Layout attaches its sublayouts, the Short Link Layout and the Long Link Layout.

Overrides:: attach in class IlvGraphLayout

Parameters:: graphModel - The graph model to lay out.
See Also:: detach(), getLongLinkLayout(), getShortLinkLayout()

detach

public void detach()

Detaches the graph model from the layout instance. It also detaches its sublayouts, the Short Link Layout and the Long Link Layout. When you attach a new graph model to the layout instance, you do not need to detach the old graph model because this is done automatically when you call attach(ilog.views.graphlayout.IlvGraphModel). The detach method performs cleaning operations on the graph model. In addition to the cleaning operations in the base class, the Link Layout removes the link style specifications of individual links.

Note that you must call this method when you no longer need the layout instance. Otherwise, some objects may not be garbage collected.

Overrides:: detach in class IlvGraphLayout

See Also:: attach(ilog.views.graphlayout.IlvGraphModel), setLinkStyle(java.lang.Object, int), getLongLinkLayout(), getShortLinkLayout()

setGraphModel

public void setGraphModel(IlvGraphModel graphModel)

Sets the graph model to be laid out. You should not call this method directly. Instead, use the method IlvGraphLayout.attach(IlvGrapher) or attach(IlvGraphModel).

Overrides:: setGraphModel in class IlvGraphLayout

Since:: JViews 5.0

layout

protected void layout(boolean redraw)
               throws IlvGraphLayoutException

Computes the layout using the Link Layout algorithm. To start the layout, call the method IlvGraphLayout.performLayout().

Specified by:: layout in class IlvGraphLayout

Parameters:: redraw - If true, the attached graph model will be asked to redraw the graph after layout. When the layout algorithm moves the nodes and reshapes the links, it is required to pass the value of the redraw argument to the methods IlvGraphModel.moveNode(java.lang.Object, float, float, boolean) and IlvGraphModel.reshapeLink(java.lang.Object, ilog.views.IlvPoint, ilog.views.IlvPoint[], int, int, ilog.views.IlvPoint, boolean).
Throws:: IlvInappropriateLinkException - if the grapher contains links that cannot be reshaped to a polyline and whose connection points cannot be moved. (For details, see IlvInappropriateLinkException).; IlvGraphLayoutException - If an unusual situation occurs. WARNING: this method can throw one of the subclasses of IlvGraphLayoutException. Specifically, it can throw an IlvInappropriateGraphException. It can also throw an IlvInappropriateLinkException when inappropriate types of links and/or link connectors are used in an IlvGrapher. For details, refer to the documentation of these exception classes.
See Also:: IlvGraphLayout.performLayout()

setLayoutMode

public final void setLayoutMode(int mode)

Sets the layout mode. Valid value are:

SHORT_LINKS - Links are placed freely in the plane by choosing the best shape from a fixed number of link shapes. A link can have a maximum of 3 bends.
This mode should be used if any of the following conditions apply:
- Most of the links are short and it is not fatal if long links overlap obstacles.
- The link routes must be placed freely and cannot be restricted to a grid.
- It is important to limit the number of bends.
LONG_LINKS - Orthogonal links are routed on a grid by avoiding obstacles. Any orthogonal link shape can occur (that is, the number of link shapes is not limited) but a long link route can have many bends. Direct links are routed with the end segments on the grid, but the middle segment may overlap obstacles.
This mode should be used if any of the following conditions apply:
- Many links are long, and it is important that long links do not overlap obstacles.
- Routing on a grid is preferred because it guarantees a minimal distance between link segments.
- An increasing number of bends is acceptable if this avoids any overlaps. The long link mode can be used to find an orthogonal route without overlaps in a labyrinth of node obstacles.

The default value is SHORT_LINKS.

See Also:: getLayoutMode(), setGlobalLinkStyle(int), setLinkStyle(java.lang.Object, int), getLongLinkLayout(), getShortLinkLayout()

getLayoutMode

public final int getLayoutMode()

Returns the current layout mode.

See Also:: setLayoutMode(int)

getShortLinkLayout

public IltShortLinkLayout getShortLinkLayout()

Returns the Short Link Layout instance that is used internally by this Link Layout instance in layout mode SHORT_LINKS. This allows you to access the internal parameter settings of the Short Link Layout.

See Also:: setLayoutMode(int), getLongLinkLayout(), IltShortLinkLayout

getLongLinkLayout

public IlvLongLinkLayout getLongLinkLayout()

Returns the Long Link Layout instance that is used internally by this Link Layout instance in layout mode LONG_LINKS. This allows you to access the internal parameter settings of the Long Link Layout.

See Also:: setLayoutMode(int), getShortLinkLayout(), IlvLongLinkLayout

contentsChanged

public void contentsChanged(GraphModelEvent event)

Overridden version of the base class method to allow the layout to be automatically restarted each time the layout instance is notified that the structure or the geometry of the graph has changed.

If auto layout is enabled (that is, IlvGraphLayout.isAutoLayout() returns true) the method calls performAutoLayout() to redo the layout.

Specified by:: contentsChanged in interface GraphModelListener
Overrides:: contentsChanged in class IlvGraphLayout

See Also:: IlvGraphLayout.isAutoLayout(), performAutoLayout()

performAutoLayout

protected void performAutoLayout()

Performs the layout again following a structural or a geometric change of the graph.

You should not call this method directly. The method is called by contentsChanged(ilog.views.graphlayout.GraphModelEvent). The default implementation simply calls the method IlvGraphLayout.performLayout(boolean, boolean) with both force and redraw arguments at true.

The method can be overridden to catch the exception IlvInappropriateLinkException thrown by the method IlvGraphLayout.performLayout(boolean, boolean) and to execute the most appropriate action. The utility method IlvGraphLayoutUtil.EnsureAppropriateLinks(ilog.views.graphlayout.IlvGraphModel, ilog.views.graphlayout.IlvLayoutProvider) can be used to replace the inappropriate links, and then the layout can be restarted.

Overrides:: performAutoLayout in class IlvGraphLayout

See Also:: setAutoLayout(boolean), contentsChanged(ilog.views.graphlayout.GraphModelEvent)

setAutoLayout

public final void setAutoLayout(boolean enable)

Enables the auto layout mode. If the argument is true, the layout is automatically performed again each time the layout instance is notified that the geometry or the structure of the graph has changed.

It is disabled by default.

Overrides:: setAutoLayout in class IlvGraphLayout

See Also:: IlvGraphLayout.isAutoLayout(), contentsChanged(ilog.views.graphlayout.GraphModelEvent), performAutoLayout()

setIncrementalMode

public final void setIncrementalMode(boolean enable)

Enables the incremental layout mode. If the argument is true, only those links that were affected by changes since the last layout are rerouted. A link is rerouted under the following conditions:

if the link is new,
if the link shape or link style has changed,
if the parameters controlling the starting and end segments have changed,
if the link now overlaps obstacles that were moved or resized,
in long link mode, if the link is no longer on the grid,
if the link is marked for incremental rerouting.

In short link mode, the rerouted links keep their general shape but adjust the bends as necessary. The rerouted links do not change the side where they are connected to the end nodes.

In long link mode, the rerouted links can change shape completely. The rerouted links can change the side where they are connected to the end nodes if this is necessary to obtain a better route.

The incremental mode works only if the intergraph links mode is disabled or if there are no intergraph links. The incremental mode is disabled by default.

See Also:: isIncrementalMode(), markForIncremental(java.lang.Object), setLayoutMode(int), contentsChanged(ilog.views.graphlayout.GraphModelEvent), setInterGraphLinksMode(boolean)

isIncrementalMode

public final boolean isIncrementalMode()

Returns true if the incremental mode is enabled.

See Also:: setIncrementalMode(boolean)

markForIncremental

public final void markForIncremental(Object link)

Marks the input link to be rerouted with the next call of performLayout if incremental mode is enabled. Normally, the incremental layout reroutes only those links that have changed since the last layout. By setting a mark on the link, this link will be rerouted even if it has not changed.

See Also:: setIncrementalMode(boolean), IlvGraphLayout.performLayout()

setInterGraphLinksMode

public final void setInterGraphLinksMode(boolean enable)

Enables the routing of intergraph links. If the argument is true, the intergraph links are routed; otherwise, only the normal links are routed. An intergraph link is a link stored in a given graph that has an origin or destination not stored in this graph. If additionally the combined intergraph link routing is enabled, this means that normal links and intergraph links are routed together; otherwise, only the intergraph links are routed.

The default value is true.

If the the intergraph link mode is enabled and the graph actually contains some intergraph links, there are some restrictions:

Layout animation is not possible.
The incremental mode has no effect.
If layout is performed on a nested IlvGrapher (or IlvGrapherAdapter), the top-level grapher must have a manager view attached because of the coordinate transformations of the subgraphers. If you create your own subclass of IlvGraphModel instead of IlvGrapherAdapter to route intergraph links, you must ensure that all graph models of all subgraphers use the same coordinate system through appropriate coordinate transformations.

Since:: JViews 5.0
See Also:: isInterGraphLinksMode(), setCombinedInterGraphLinksMode(boolean), setAnimate(boolean), setIncrementalMode(boolean), IlvGraphModel.isInterGraphLink(java.lang.Object)

isInterGraphLinksMode

public final boolean isInterGraphLinksMode()

Returns true if the routing of intergraph links is enabled. Returns false otherwise.

Since:: JViews 5.0
See Also:: setInterGraphLinksMode(boolean)

setCombinedInterGraphLinksMode

public final void setCombinedInterGraphLinksMode(boolean enable)

Enables the routing of normal links in addition to intergraph links. If intergraph link routing is disabled, the option has no effect. If intergraph link routing is enabled and the argument is true, both normal links and intergraph links are routed in the same pass. Otherwise, only the intergraph links are routed.

The default value is true.

Since:: JViews 5.0
See Also:: isCombinedInterGraphLinksMode(), setInterGraphLinksMode(boolean), IlvGraphModel.isInterGraphLink(java.lang.Object)

isCombinedInterGraphLinksMode

public final boolean isCombinedInterGraphLinksMode()

Returns true if the routing of normal links in addition to intergraph links is enabled. It returns false otherwise.

Since:: JViews 5.0
See Also:: setInterGraphLinksMode(boolean), setCombinedInterGraphLinksMode(boolean)

setLinkOffset

public final void setLinkOffset(float offset)

Sets the offset between links connected on the same side of the node. It affects only the layout mode SHORT_LINKS where the links are placed freely. In the layout mode LONG_LINKS, the link offset parameter is ignored, because the offset between links is implicitly determined by the grid width.

The default value is 2.

See Also:: getLinkOffset(), setLayoutMode(int), setHorizontalGridOffset(float), setVerticalGridOffset(float)

getLinkOffset

public final float getLinkOffset()

Returns the offset between links connected on the same side of the node. This offset affects only the layout mode SHORT_LINKS.

See Also:: setLinkOffset(float)

setHorizontalGridOffset

public final void setHorizontalGridOffset(float offset)

Sets the horizontal offset between the grid lines. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 5.

See Also:: getHorizontalGridOffset(), setHorizontalMinOffset(float), setHorizontalGridBase(float), setLinkOffset(float), setLayoutMode(int)

getHorizontalGridOffset

public final float getHorizontalGridOffset()

Returns the horizontal offset between the grid lines. This offset affects only the layout mode LONG_LINKS.

See Also:: setHorizontalGridOffset(float)

setVerticalGridOffset

public final void setVerticalGridOffset(float offset)

Sets the vertical offset between the grid lines. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 5.

See Also:: getVerticalGridOffset(), setVerticalMinOffset(float), setVerticalGridBase(float), setLinkOffset(float), setLayoutMode(int)

getVerticalGridOffset

public final float getVerticalGridOffset()

Returns the vertical offset between the grid lines. This offset affects only the layout mode LONG_LINKS.

See Also:: setVerticalGridOffset(float)

setHorizontalGridBase

public final void setHorizontalGridBase(float coordinate)

Sets the horizontal base coordinate of the grid. This is the x coordinate of the first vertical grid line. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 0.

See Also:: getHorizontalGridBase(), setHorizontalGridOffset(float), setLayoutMode(int)

getHorizontalGridBase

public final float getHorizontalGridBase()

Returns the horizontal base coordinate of the grid. This value affects only the layout mode LONG_LINKS.

See Also:: setHorizontalGridBase(float)

setVerticalGridBase

public final void setVerticalGridBase(float coordinate)

Sets the vertical base coordinate of the grid. This is the y coordinate of the first horizontal grid line. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 0.

See Also:: getVerticalGridBase(), setVerticalGridOffset(float), setLayoutMode(int)

getVerticalGridBase

public final float getVerticalGridBase()

Returns the vertical base coordinate of the grid. This value affects only the layout mode LONG_LINKS.

See Also:: setVerticalGridBase(float)

setHorizontalMinOffset

public final void setHorizontalMinOffset(float offset)

Sets the minimal horizontal offset between the node border and a link segment that is (vertically) parallel to the node border. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 3.

See Also:: getHorizontalMinOffset(), setHorizontalGridOffset(float), setLayoutMode(int)

getHorizontalMinOffset

public final float getHorizontalMinOffset()

Returns the minimal horizontal offset between the node border and a link segment that is (vertically) parallel to the node border. This value affects only the layout mode LONG_LINKS.

See Also:: setHorizontalMinOffset(float)

setVerticalMinOffset

public final void setVerticalMinOffset(float offset)

Sets the minimal vertical offset between the node border and a link segment that is (horizontally) parallel to the node border. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid. In the layout mode SHORT_LINKS, links are placed freely and the grid parameters are ignored.

The default value is 3.

See Also:: getVerticalMinOffset(), setVerticalGridOffset(float), setLayoutMode(int)

getVerticalMinOffset

public final float getVerticalMinOffset()

Returns the minimal vertical offset between the node border and a link segment that is (horizontally) parallel to the node border. This value affects only the layout mode LONG_LINKS.

See Also:: setVerticalMinOffset(float)

setMinNodeCornerOffset

public final void setMinNodeCornerOffset(float offset)

Sets the minimum offset between a node corner and a link starting at this node. Setting this to 0 enables the layout to start a link exactly at a node corner. It affects only the layout mode LONG_LINKS where the links are routed on an orthogonal grid and always connect to the node border. In the layout mode SHORT_LINKS, links are placed freely in the plane, potentially connecting outside the node border.

The default value is 3.

See Also:: getMinNodeCornerOffset(), setLayoutMode(int)

getMinNodeCornerOffset

public final float getMinNodeCornerOffset()

Returns the minimum offset between a node corner and a link starting at this node. This value affects only the layout mode LONG_LINKS.

See Also:: setMinNodeCornerOffset(float)

setMinFinalSegmentLength

public final void setMinFinalSegmentLength(float length)

Sets the minimum length of the first and last segments of each link.

The default value is 10.

See Also:: getMinFinalSegmentLength()

getMinFinalSegmentLength

public final float getMinFinalSegmentLength()

Returns the minimum length of the first and last segments of each link.

See Also:: setMinFinalSegmentLength(float)

setGlobalLinkStyle

public final void setGlobalLinkStyle(int style)

Sets the global style of the shapes of links. Valid values are:

ORTHOGONAL_STYLE - all links have an orthogonal shape, that is, a shape consisting of a sequence of alternating horizontal and vertical line segments.
DIRECT_STYLE - all links get a nearly straight-line shape. The shape of the links is a polyline composed of a straight-line segment between the end nodes with two short horizontal or vertical segments at its ends (their length is controlled by the method setMinFinalSegmentLength and may be 0).
MIXED_STYLE - each link can have a different link style. The style of each individual link can be set by the method setLinkStyle(Object, int) so that different link shapes can occur in the same graph.

Unless the global link style is MIXED_STYLE, all links have the same shape style.

The default value is ORTHOGONAL_STYLE.

Note that when the graph attached to the layout is of type IlvGrapher, the effect of the link reshaping depends on the type of the links and the connectors installed at the node. For all link styles, we recommend using links of type IlvPolylineLinkImage and link connectors of type IlvRelativeLinkConnector. Other link or connector types may cause an IlvInappropriateLinkException during layout. You can use the method IlvGraphLayoutUtil.EnsureAppropriateLinkTypes(ilog.views.graphlayout.IlvGraphLayout, boolean) and method IlvGraphLayoutUtil.EnsureAppropriateLinkConnectors(ilog.views.graphlayout.IlvGraphLayout, boolean) before layout, or the method IlvGraphLayoutUtil.EnsureAppropriateLinks(ilog.views.graphlayout.IlvGraphModel, ilog.views.graphlayout.IlvLayoutProvider) when the exception is caught, to convert all links and link connectors to an appropriate type.

See Also:: getGlobalLinkStyle(), setLinkStyle(java.lang.Object, int), setLayoutMode(int)

getGlobalLinkStyle

public final int getGlobalLinkStyle()

Returns the global style of the shapes of links.

See Also:: setGlobalLinkStyle(int)

setLinkStyle

public final void setLinkStyle(Object link,
                               int style)

Sets the shape style of an individual link. This link style is used only if the global link style is set to MIXED_STYLE. Otherwise, all links have the style that is specified as the global link style.

Valid values are:

ilog.tgo.graphic.graphlayout Class IltLinkLayout

ORTHOGONAL_STYLE

DIRECT_STYLE

MIXED_STYLE

NO_RESHAPE_STYLE

SHORT_LINKS

LONG_LINKS

IltLinkLayout

IltLinkLayout

init

copy

copyParameters

attach

detach

setGraphModel

layout

setLayoutMode

getLayoutMode

getShortLinkLayout

getLongLinkLayout

contentsChanged

performAutoLayout

setAutoLayout

setIncrementalMode

isIncrementalMode

markForIncremental

setInterGraphLinksMode

isInterGraphLinksMode

setCombinedInterGraphLinksMode

isCombinedInterGraphLinksMode

setLinkOffset

getLinkOffset

setHorizontalGridOffset

getHorizontalGridOffset

setVerticalGridOffset

getVerticalGridOffset

setHorizontalGridBase

getHorizontalGridBase

setVerticalGridBase

getVerticalGridBase

setHorizontalMinOffset

getHorizontalMinOffset

setVerticalMinOffset

getVerticalMinOffset

setMinNodeCornerOffset

getMinNodeCornerOffset

setMinFinalSegmentLength

getMinFinalSegmentLength

setGlobalLinkStyle

getGlobalLinkStyle

setLinkStyle

ilog.tgo.graphic.graphlayout
Class IltLinkLayout