com.ur.urcap.api.domain.program.structure

Interface TreeNode

public interface TreeNode

The TreeNode represents a node in the program tree that can be used to construct a sub-tree rooted in a URCap program node. Using the ProgramModel.getRootTreeNode(ProgramNodeContribution) to obtain a root for the sub-tree, it is possible to add children. For each call to addChild(ProgramNode), a new TreeNode is returned, that can, in turn, act as a root for yet another sub-tree.

Method Summary

Modifier and Type	Method and Description
TreeNode	addChild(ProgramNode programNode) Add a child to this TreeNode
List<TreeNode>	getChildren()
ProgramNode	getProgramNode()
TreeNode	insertChildAfter(TreeNode existingChildNode, ProgramNode programNode) Inserts a child under this TreeNode directly after the existing selected child node.
TreeNode	insertChildBefore(TreeNode existingChildNode, ProgramNode programNode) Inserts a child under this TreeNode directly before the existing selected child node.
boolean	removeChild(TreeNode child) Removes a child from the sub-tree.
TreeNode	setChildSequenceLocked(boolean isChildSequenceLocked) Means that the children can not be rearranged, deleted or have other nodes inserted into the child sequence by the end user.
void	traverse(ProgramNodeVisitor nodeVisitor) This method traverses the entire sub-tree under this tree node in a depth-first fashion (this corresponds to a top-down approach in the program tree).

Method Detail

addChild

TreeNode addChild(ProgramNode programNode)
           throws TreeStructureException

Add a child to this TreeNode

Parameters:

programNode - the ProgramNode constructed using the ProgramNodeFactory

Returns:

Returns a TreeNode that can be used to add children to the newly added child.

Throws:

TreeStructureException - If it is not allowed to insert the ProgramNode at this position a TreeStructureException will be thrown.

insertChildBefore

TreeNode insertChildBefore(TreeNode existingChildNode,
                           ProgramNode programNode)
                    throws TreeStructureException

Inserts a child under this TreeNode directly before the existing selected child node. Shifts the selected child node and any subsequent nodes to positions after the newly added child.

Parameters:

existingChildNode - existing TreeNode child of this TreeNode

programNode - the ProgramNode constructed using the ProgramNodeFactory

Returns:

Returns a TreeNode that can be used to add children to the newly added child.

Throws:

TreeStructureException - If it is not allowed to insert the ProgramNode at this position or if the selected child node is not a child of this TreeNode a TreeStructureException will be thrown.

insertChildAfter

TreeNode insertChildAfter(TreeNode existingChildNode,
                          ProgramNode programNode)
                   throws TreeStructureException

Inserts a child under this TreeNode directly after the existing selected child node. Shifts any subsequent nodes to positions after the newly added child.

Parameters:

existingChildNode - existing TreeNode child of this TreeNode

programNode - the ProgramNode constructed using the ProgramNodeFactory

Returns:

Returns a TreeNode that can be used to add children to the newly added child.

Throws:

TreeStructureException - If it is not allowed to insert the ProgramNode at this position or if the selected child node is not a child of this TreeNode a TreeStructureException will be thrown.

removeChild

boolean removeChild(TreeNode child)
             throws TreeStructureException

Removes a child from the sub-tree. Be aware that removing the last child will trigger the insertion of an <empty> child node.

Parameters:

child - The TreeNode child to be removed.

Returns:

Returns true if removed successfully. False otherwise.

Throws:

TreeStructureException - If the removed child would leave the tree in an illegal state a TreeStructureException will be thrown.

getChildren

List<TreeNode> getChildren()

Returns:

a List of TreeNodes that represent all the children of this TreeNode (both programmatically added as well as user inserted).

getProgramNode

ProgramNode getProgramNode()

Returns:

Returns the ProgramNode at this position in the sub-tree. Can either be a built-in PolyScope program node (provided by Universal Robots) or a URCap program node.

setChildSequenceLocked

TreeNode setChildSequenceLocked(boolean isChildSequenceLocked)

Means that the children can not be rearranged, deleted or have other nodes inserted into the child sequence by the end user.

Parameters:

isChildSequenceLocked - If true then the immediate children under this TreeNode will be locked

Returns:

The same TreeNode

traverse

void traverse(ProgramNodeVisitor nodeVisitor)

This method traverses the entire sub-tree under this tree node in a depth-first fashion (this corresponds to a top-down approach in the program tree). The nodeVisitor is used for callbacks to the visit-overloads you choose to override. The overload called depends on the node type encountered. Override the overloads for the node types you are concerned with. All visit methods have the program node, sibling index and depth as arguments to help filter nodes if needed. The nodeVisitor can be either a ProgramNodeVisitor implementation with optional overrides or a URCapProgramNodeInterfaceVisitor implementation. In the latter case, the URCapProgramNodeInterfaceVisitor.visitURCapAs(Object, int, int) method must be implemented. The URCapProgramNodeInterfaceVisitor can be used when targeting URCap program nodes implementing the (generic) type parameter specified in URCapProgramNodeInterfaceVisitor (see also URCapProgramNode.getAs(Class)). Note that this method is sometimes called accept() in the Visitor software design pattern.

Parameters:

nodeVisitor - the instance callbacks are made to.