void (PsiElement source, PsiElement target) { Node from = myElementToNode.get(source); Node to = myElementToNode.get(target); if (from == null) { from = new Node(source); if (source instanceof PsiExpression) myExpressionsQueue.addLast((PsiExpression)source); myElementToNode.put(source, from); } if (to == null) { to = new Node(target); if (target instanceof PsiExpression) myExpressionsQueue.addLast((PsiExpression)target); myElementToNode.put(target, to); } Edge.connect(from, to); }