ilog.views.graphlayout.hierarchical

Class IlvSideBySideConstraint

java.lang.Object

ilog.views.graphlayout.hierarchical.IlvHierarchicalConstraint

ilog.views.graphlayout.hierarchical.IlvSideBySideConstraint

All Implemented Interfaces:

IlvPersistentObject, Serializable

public class IlvSideBySideConstraint
extends IlvHierarchicalConstraint

The class IlvSideBySideConstraint is a constraint that forces a group of nodes that belong to the same level to be placed side by side. It prohibits that other nodes of the same level are placed in the middle of the group. By this, the relative positions of the nodes of the group are close together. It does not affect the order of nodes that belong to different levels.

Nodes are organized in horizontal or vertical levels. Within each level, the nodes are placed sequentially at relative positions numbered from 0 to "n". The constraint specifies that those nodes of the group that belong to the same level are placed in subsequent positions within the level. The constraint is ignored, if all nodes of the group belong to different levels.

For instance, assume the group consists of nodes A, B, C, D, E. If A, B and C belong to one level and D and E to another level, then the side by side constraint forces the nodes A, B, C to be placed side by side, and D and E to be placed side by side. The constraint is satisfied if the positions of A, B, C are 5, 6, 7 and the positions of D and E are 1 and 2. The constraint affects only the nodes that belong to the same level, therefore the constraint affects the subgroup ( A, B, C ) and the subgroup ( D, E ) individually, not the entire group ( A, B, C, D, E ) as a unit. The constraint is not satisfied if the positions of A, B and C are 5, 7 and 8, because in this case, there must be a node between A and B that does not belong to the same group. The node between A and B cannot be D or E, because D and E belong to a different level.

The constraint is evaluated, if the incremental mode is disabled. If the incremental mode is enabled, the constraint is only evaluated if the nodes of the group are marked for incremental recalculation, because otherwise, the incremental positions of the nodes are dominant.

This kind of constraint dominates the relative position constraints. The constraints have priorities. If several conflicting constraints are specified (such as a node must be side by side to three different groups), the constraints with lower priority are ignored during layout. The constraint is dominated by specified position indexes, i.e. it does not change the order of nodes that have specified position indexes, and by swimlane constraints, that is, it is not able to break swimlanes apart.

The automatic conflict resolution can handle conflicting constraints. However, to speed up the layout, it is recommended to specify constraints in a way such that there are no conflicts.

In recursive layout mode (see IlvHierarchicalLayout.setRecursiveLayoutMode(boolean)), all nodes of the group of a side by side constraint must belong to the same subgraph, and the constraint must be installed at the layout instance that is attached to this subgraph. It is not possible to have a side by side constraint containing a group of nodes of different subgraphs.

Since:

JViews 5.0

See Also:

IlvHierarchicalLayout.addConstraint(IlvHierarchicalConstraint), IlvHierarchicalLayout.setIncrementalMode(boolean), IlvHierarchicalLayout.markForIncremental(Object), Serialized Form

Constructor Summary

Constructors

Constructor and Description
IlvSideBySideConstraint(IlvInputStream stream) Creates a new IlvSideBySideConstraint from an IlvInputStream.
IlvSideBySideConstraint(IlvNodeGroup groupArg, float priorityArg) Creates a new IlvSideBySideConstraint .
IlvSideBySideConstraint(IlvSideBySideConstraint source) Creates a new IlvSideBySideConstraint by copying an existing one.

Method Summary

Modifier and Type	Method and Description
IlvHierarchicalConstraint	copy() Copies the constraint.
IlvNodeGroup	getGroup() Returns the group of this constraint.
void	write(IlvOutputStream stream) Writes the constraint to the output stream.

Methods inherited from class ilog.views.graphlayout.hierarchical.IlvHierarchicalConstraint

getPriority, setPriority

Methods inherited from class java.lang.Object

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

Constructor Detail

IlvSideBySideConstraint

public IlvSideBySideConstraint(IlvNodeGroup groupArg,
                               float priorityArg)

Creates a new IlvSideBySideConstraint .

The following examples show how to use the constraint:

 layout.addConstraint(
     new IlvSideBySideConstraint(new IlvNodeGroup(nodeVector), priority)); 

This forces those nodes of nodeVector that belong to the same level to be placed side by side.

Parameters:

groupArg - The node group.

priorityArg - The priority of the constraint.

See Also:

IlvHierarchicalLayout.addConstraint(IlvHierarchicalConstraint)

IlvSideBySideConstraint

public IlvSideBySideConstraint(IlvSideBySideConstraint source)

Creates a new IlvSideBySideConstraint by copying an existing one.

Parameters:

source - The origin of the copy.

IlvSideBySideConstraint

public IlvSideBySideConstraint(IlvInputStream stream)
                        throws IOException,
                               IlvReadFileException

Creates a new IlvSideBySideConstraint from an IlvInputStream.

Parameters:

stream - The input stream from which the property must be read.

Throws:

IlvReadFileException - if an error occurs while reading.

IOException

Method Detail

copy

public IlvHierarchicalConstraint copy()

Copies the constraint.

Specified by:

copy in class IlvHierarchicalConstraint

write

public void write(IlvOutputStream stream)
           throws IOException

Writes the constraint to the output stream.

Specified by:

write in interface IlvPersistentObject

Overrides:

write in class IlvHierarchicalConstraint

Parameters:

stream - The output stream.

Throws:

IOException - standard IO error.

getGroup

public final IlvNodeGroup getGroup()

Returns the group of this constraint.