public void changeClosure(Statement stat) {
    if (this.closure != null) {
      this.closure.getLabelEdges().remove(this);
    }
    this.closure = stat;
    if (this.closure != null) {
      this.closure.getLabelEdges().add(this);
    }
  }
Remove the closure of this edge. This edge will no
longer be labeled.
src/org/jetbrains/java/decompiler/modules/decompiler/StatEdge.java