static DoubleLinkNode[] build() { DoubleLinkNode a = new DoubleLinkNode('a'); DoubleLinkNode b = new DoubleLinkNode('b'); DoubleLinkNode c = new DoubleLinkNode('c'); DoubleLinkNode d = new DoubleLinkNode('d'); DoubleLinkNode e = new DoubleLinkNode('e'); a.next = b; b.pre = a; b.next = c; c.pre = b; c.next = d; d.pre = c; d.next = e; e.pre = d; DoubleLinkNode[] list = new DoubleLinkNode[3]; list[0] = a; list[1] = c; list[2] = e; return list; }