Class SoSearchAction

  • Direct Known Subclasses:
    SoSearchPathAction, SoSearchStepAction

    public class SoSearchAction
    extends SoAction
    Searches for nodes in a scene graph. This class is used to search scene graphs for specific nodes, nodes of a specific type, nodes with a specific name, or any combination of these. It can search for just the first or last node satisfying the criteria or for all such nodes. The action returns a path (SoPath) to each node found. The searched for node is the "tail" of each path.

    Note that the search criteria are cumulative. For example, if you do a search by name (setName()), then reuse the same SoSearchAction object to do a search by type (setType()), the action will actually search for a node that satisfies both criteria. To avoid this problem, call reset() before reusing the action object.

    By default SoSearchAction only searches nodes that are actually traversed. For example it would not search all the children of an SoSwitch node unless the whichChild field is set to SO_SWITCH_ALL. To search all nodes in the scene graph (except nodekits - see next paragraph) call setSearchingAll(true).

    Nodekits:

    • By default SoSearchAction will not search inside nodekits even when setSearchingAll is true. This is because nodekits try to keep their children hidden. To allow searching inside nodekits call the static method SoBaseKit.setSearchingChildren(true).
    • A common problem is that when the searched for node is found inside a nodekit, the SoPath method regular.getTail() does not return the found node. This is also because nodekits try to keep their children hidden. To avoid this problem use full.getTail() instead. Hidden references:

      SoSearchAction creates one or more SoPath objects when applied to the scene graph. The SoPath object references each node in the path. This reference will prevent the node and its associated memory from being reclaimed for as long as the SoPath object exists. These SoPath objects are stored internally in the action and exist until the action object itself is reclaimed or reset.

      Efficiency:

      SoSearchAction is convenient for finding one or many nodes in the scene graph. However it may be an inefficient solution for finding a large number of nodes because it uses CPU time and memory to create an SoPath for every node found. If you expect to find many nodes, especially if you just need the node object and not a path, then you should consider using SoCallbackAction instead.

      For example, if you want to count all the shape nodes in the scene graph, you could use an SoSearchAction similar to the second example below. The number of shapes would conveniently be the number of paths created by the action, but you wouldn't actually make any use of the path information. Using SoCallbackAction would be a little more work, because you have to implement a counter in a callback class. But it would be much more efficient because the action simply calls your callback when each shape node is visited during the traversal.

      EXAMPLE

    Example 1: Given an instance of a node, create a path to the location of that node in the scene graph:

     SoSearchAction sa = new SoSearchAction();
         sa.setNode( cone );
         sa.setSearchingAll( true );              // Optional: Search all nodes
         SoBaseKit.setSearchingChildren( true );  // Optional: Search inside nodekits
         sa.apply( root );
         SoPath path = sa.getPath();
         if (path != null) {
             SoNode node = path.regular.getTail();
         }

    Example 2: Find all the SoFont nodes in the scene graph:

     SoSearchAction sa = new SoSearchAction();
       sa.setNodeClass( SoFont.class );
       sa.setInterest( SoSearchAction.Interests.ALL );   // Find ALL instances
       sa.setSearchingAll( true );              // Optional: Search all nodes
       SoBaseKit.setSearchingChildren( true );  // Optional: Search inside nodekits
       sa.apply( rootNode );
       java.util.Vector<SoPath> pathList = sa.getPaths();
       if (! pathList.isEmpty()) {
           SoPath path = pathList.get( 0 );
           SoFont fontNode = (SoFont)path.regular.getTail();
       }

    See Also:
    SoPath, SoBaseKit, SoSearchPathAction, SoSearchStepAction
    • Constructor Detail

      • SoSearchAction

        public SoSearchAction()
        Constructor.
    • Method Detail

      • setNodeClass

        public void setNodeClass​(java.lang.Class<? extends Inventor> t)
        Calls setNodeClass(t, true).
      • getFind

        public int getFind()
        Returns what to look for.
      • setNode

        public void setNode​(SoNode n)
        Sets the node to search for.
      • addPath

        public void addPath​(SoPath path)
      • getNode

        public SoNode getNode()
        Returns the node to search for.
      • setFind

        public void setFind​(int what)
        Sets what to look for; what is a bitmask of LookFor enum values. Default is no flags at all. Note that setting a node, type, and/or name to search for activates the relevant flag, so you may never need to call this method directly.
      • isSearchingExtendedClass

        public boolean isSearchingExtendedClass()
        Returns the node type to search for.
      • isSearchingAll

        public boolean isSearchingAll()
        Returns false if searching uses regular traversal, true if it traverses every single node. Default is false.
      • reset

        public void reset()
        Resets options back to default values; clears list of returned paths. This can be used to apply the action again with a different set of search criteria. See also clearApplyResult().
      • isFound

        public boolean isFound()
      • getPaths

        public java.util.Vector<SoPath> getPaths()
        Returns resulting path list. This should be used if the interest is ALL.
      • setSearchingAll

        public void setSearchingAll​(boolean flag)
        Sets whether searching uses regular traversal or whether it traverses every single node. For example, if this flag is false, an SoSwitch node will traverse only the child or children it would normally traverse for an action. If the flag is true, the switch would always traverse all of its children. The default is false.
      • getPath

        public SoPath getPath()
        Returns resulting path, or NULL if no path was found. This should be used if the interest is FIRST or LAST.
      • setName

        public void setName​(java.lang.String n)
        Sets the name of the node to search for.
      • setFound

        public void setFound()
      • getNodeClass

        public java.lang.Class<? extends Inventor> getNodeClass()
        Returns the node type to search for.
      • setNodeClass

        public void setNodeClass​(java.lang.Class<? extends Inventor> t,
                                 boolean derivedIsOk)
        Sets the node type to search for. If derivedIsOk is true, a node that is of a type that is derived from t will pass this search criterion.
      • enableElement

        public static void enableElement​(java.lang.Class<? extends Inventor> t,
                                         int stkIndex)
      • getName

        public java.lang.String getName()
        Returns the name of the node to search for.