JMatchJava模式匹配庫(kù)

示例代碼：

static RBNode balance(int color, int value, RBTree left, RBTree right)
{
  if (color == BLACK) {
    switch (value,left,right) {
      case int z,
           RBNode(RED,int y,RBNode(RED,int x,RBTree a,RBTree b),RBTree c),
           RBTree d:
      case z, RBNode(RED,x,a,RBNode(RED,y,b,c)),d:
      case x, a, RBNode(RED,z,RBNode(RED,y,b,c),d):
      case x, a, RBNode(RED,y,b,RBNode(RED,z,c,d)):
        return RBNode(RED,y,RBNode(BLACK,x,a,b),RBNode(BLACK,z,c,d));
    }
  }
  return RBNode(color, value, left, right);
}