UmlPanel is an component used to make and view UML diagrams. Whole project is divided in two part, one  is data part which gives you possibility to create, store  or add complet UML diagram. Second part is an graphical representation of the same diagram. Fisrt (data part) can be used without using graphical representation, second part (graphical representation) logicaly can't exist without data part.

Here is UmlManipulator diagram:

Possible operation with data part (in fallowing text DP):

Programaticaly create an UML diagram. Save complet UML diagram in XML format. Load UML diagram from XML format.

Possible operation with graphical part (in fallowing text GP)

Graphical representation of UML diagram. Changing size of each node. Making conections in between nodes. Selecting one or more node. Changing position of nodes. Turn on/off grid for easyest manipulation. Showing captions and other data associated with given node.

How all those stuffs work?

Data Part (DP)

Here is DP diagram. As you can see data part contains two basic classes:   CUmlDiagram CNode This two class are necessery minimum to desribe an UML diagram. CUmlDiagram is class which provide functionality for loading and saving UML diagram, in same time it holds list of nodes in UML diagram. CNode class is an abstract class and it need to be extended by any new class. It contains only basic functionality such as conection to it graphical representation class (CVisNode). Extended class from CNode class can represents (in UML diagram) class,interface,connection etc.

In case if we dont want to have any graphical representation of UML diagram we can use only DP classes. They have functionality for programaticaly creating an UML diagram, saving or loading it. Offcourse in real life it could be very difficult to make an diagram without seen a real graphical representation of it. Any of CNode childrens can have it own graphical representation. This graphical representation can be customized by any user who wants top change "look&feel" of diagram". Those classes are added to CNode by giving String parameter with full package name and class which will represent our CNode children class. Graphical represenation class must be extended from abstract class CVisNode. In case if we want to have full graphical representation we also need to conect Observers to our CUmlDiagram class.

Those two classes represent connection in between graphical representation and DP. Instance of CActionObserver have to be added to CUmlDiagram. Trough this observer CUmlDiagram inform class which implements IPaintListener that UML diagram was changed (Node was moved, added, deleted etc). For this operation CUmlDiagram send list of nodes to be updated same as clip region for this update. In simple any kind of action on diagram must "fly" trough thid observer. On the other hand CUserEventObserver is responisble for any kind of user events in graphical representation of diagram. For example mouse or keyboard operations. Class CUmlCanvas have to know about this Observer same as this observer have to know about CUmlCanvas. CUserEventObserver implements all interfaces for listening mouse and keyboard events.It also knows about CUmlDiagram instance so it can ask CUmlDiagram for node which was afected by user operation and inform CUmlCanvas that it must do some operation with this node, such as draw selection rectangle, move node, etc.

Graphical representation part (GP)

On first look GP parat have similar construction as data part. CUmlCanvas class is responisble for drawing whole diagram. It is also responisble for drawing manipulating primitives (xor rectangle for moving nodes, etc). Class CVisNode is an abstract class from which have to be extended all other classes which will represent data part of diagram. CUmlCanvas also implement IPaintListener interface for comunication with CActionObserver class. Any kind of data such as position or size of given node are stored in data part of node. CVisNode is only responible for proper draving node on screen. It is only on user how he want to represent all kind of data nodes.

Class Description

DataPart CUmlDiagram CNode

Observer Part CActionObserver CUserEventObserver

Graphical Part IPaintListener CUmlCanvas CVisNode

CUmlDiagram public class CUmlDiagram extends java.lang.Object An class which hold all data from an UML diagram. Constructor Summary CUmlDiagram()        Construct new diagram. Method Summary Vector getNodes()       Return list of existing nodes. Each item is CNode type. void setActionObserver(CActionObserver observer)    Set ActionObserver for graphical representation of diagram.

CNode public abstract class CNode extends java.lang.Object An abstract class need to be extended by new representations of UML elements (class,interface,arrows etc) Constructor Summary CNode()        Construct new node. CNode(String path)        Construct new node with graphical representation given by parameter path, which is full package and class name of class used for graphical representation. Method Summary Rectangle getClientRect()    Return client rectangle. void setSize(Dimension d)    Set client size. void setLocation(Point p)    Set location of node. boolean isSelected()    Return true if given node is selected otherwise return false.

CActionObserver public class CActionObserver extends java.lang.Object Class which take care of all actions between data part and visual representation of it. Constructor Summary CActionObserver()    Create new instance of CActionObserver. Method Summary CActionObserver static getInstance()    Return static instance of CActionObserver class.

CUserEventObserver public class CUserEventObserver extends java.lang.Object Observer class which implements all action listeners for mouse and keyboard events used by CUmlCanvas.It make communication between DP and GP. Constructor Summary CUserEventObserver()    Create new instance of CUserEventObserver. Method Summary CUserEventObserver static getInstance()    Return static instance of CUserEventObserver

IPaintListener public interface IPaintListener Listener used by CActionObserver Method Summary void repaint(Rectangle clip,Vector nodes)       Repaint area given by clip parameter, nodes parameter contains all nodes to be repainted.

CUmlCanvas public class CUmlCanvas extends java.awt.Canvas Class used to paint UML diagram, also provide functionality for visualisation of moving or resizing nodes. Constructor Summary CUmlCanvas()        Construct new canvas. CUmlCanvas(CUserEventObserver observer)        Construct new canvas with User event observer. Method Summary void setUserEventObserver(CUserEventObserver observer)       Set User event observer, and use it as an mouse and keyboarb listener.

CVisNode public abstract class VisNode extends java.awt.Object Abstract class as an representation of nodes in UML diagram. Constructor Summary CVisNode()    Create new instance of CVisNode. Method Summary Vector draw(CNode node,Graphics g)    Draw given node on graphics context g.