{"id":15226,"date":"2023-12-04T17:44:24","date_gmt":"2023-12-04T09:44:24","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=15226"},"modified":"2023-12-15T16:44:10","modified_gmt":"2023-12-15T08:44:10","slug":"zookeeper-zhong-ke-hu-duan-zhu-cewatcher-shi-ru-he","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/12\/04\/zookeeper-zhong-ke-hu-duan-zhu-cewatcher-shi-ru-he\/","title":{"rendered":"ZooKeeper\u4e2d\u5ba2\u6237\u7aef\u6ce8\u518cWatcher\u662f\u5982\u4f55\u5b9e\u73b0\u7684\uff1f"},"content":{"rendered":"

\u5728ZooKeeper\u4e2d\uff0c\u5ba2\u6237\u7aef\u6ce8\u518cWatcher\u662f\u901a\u8fc7\u5728\u8bfb\u53d6ZNode\u6570\u636e\u6216\u68c0\u6d4bZNode\u7684\u72b6\u6001\u65f6\u5411ZooKeeper\u670d\u52a1\u5668\u6ce8\u518cWatcher\u6765\u5b9e\u73b0\u7684\u3002Watcher\u662f\u4e00\u79cd\u4e8b\u4ef6\u673a\u5236\uff0c\u5b83\u5141\u8bb8\u5ba2\u6237\u7aef\u5728ZooKeeper\u4e2d\u7684ZNode\u4e0a\u8bbe\u7f6e\u76d1\u89c6\u70b9\uff0c\u4e00\u65e6ZNode\u7684\u72b6\u6001\u53d1\u751f\u53d8\u5316\uff0c\u670d\u52a1\u5668\u5c31\u4f1a\u901a\u77e5\u5ba2\u6237\u7aef\u3002<\/p>\n

\u5177\u4f53\u6b65\u9aa4\u5982\u4e0b\uff1a<\/p>\n

    \n
  1. \n\u5ba2\u6237\u7aef\u521b\u5efaZooKeeper\u8fde\u63a5\uff1a<\/strong><\/p>\n
      \n
    • \u5ba2\u6237\u7aef\u901a\u8fc7ZooKeeper\u63d0\u4f9b\u7684API\u521b\u5efa\u4e00\u4e2a\u5230ZooKeeper\u670d\u52a1\u5668\u7684\u8fde\u63a5\u3002<\/li>\n<\/ul>\n<\/li>\n
    • \n\u5728ZNode\u4e0a\u6ce8\u518cWatcher\uff1a<\/strong><\/p>\n
        \n
      • \u5ba2\u6237\u7aef\u53ef\u4ee5\u901a\u8fc7\u8bfb\u53d6ZNode\u7684\u6570\u636e\u6216\u68c0\u6d4bZNode\u7684\u72b6\u6001\u7684\u64cd\u4f5c\u4e2d\uff0c\u9009\u62e9\u5728ZNode\u4e0a\u6ce8\u518cWatcher\u3002\u8fd9\u53ef\u4ee5\u901a\u8fc7API\u4e2d\u7684\u65b9\u6cd5\u5b8c\u6210\uff0c\u4f8b\u5982getData()<\/code>\u3001exists()<\/code>\u7b49\u3002<\/li>\n<\/ul>\n<\/li>\n
      • \n\u670d\u52a1\u5668\u901a\u77e5Watch\u4e8b\u4ef6\uff1a<\/strong><\/p>\n
          \n
        • \u5f53ZNode\u7684\u6570\u636e\u53d1\u751f\u53d8\u5316\u6216ZNode\u7684\u72b6\u6001\u53d1\u751f\u53d8\u5316\u65f6\uff0cZooKeeper\u670d\u52a1\u5668\u4f1a\u5411\u6240\u6709\u5728\u8be5ZNode\u4e0a\u6ce8\u518c\u4e86Watcher\u7684\u5ba2\u6237\u7aef\u53d1\u9001\u4e8b\u4ef6\u901a\u77e5\u3002<\/li>\n<\/ul>\n<\/li>\n
        • \n\u5ba2\u6237\u7aef\u5904\u7406Watch\u4e8b\u4ef6\uff1a<\/strong><\/p>\n
            \n
          • \u5ba2\u6237\u7aef\u5728\u6536\u5230Watch\u4e8b\u4ef6\u901a\u77e5\u540e\uff0c\u53ef\u4ee5\u6267\u884c\u7279\u5b9a\u7684\u5904\u7406\u903b\u8f91\u3002\u8fd9\u53ef\u4ee5\u5305\u62ec\u91cd\u65b0\u8bfb\u53d6ZNode\u7684\u6570\u636e\uff0c\u68c0\u67e5ZNode\u7684\u72b6\u6001\u53d8\u5316\u7b49\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n

            \u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cWatcher\u662f\u4e00\u6b21\u6027\u7684\uff0c\u5373\u4e00\u65e6\u89e6\u53d1\u4e86Watch\u4e8b\u4ef6\uff0c\u5b83\u5c31\u4f1a\u88ab\u4eceZooKeeper\u670d\u52a1\u5668\u4e0a\u79fb\u9664\u3002\u56e0\u6b64\uff0c\u5728\u5904\u7406\u5b8cWatch\u4e8b\u4ef6\u540e\uff0c\u5ba2\u6237\u7aef\u901a\u5e38\u9700\u8981\u91cd\u65b0\u6ce8\u518cWatcher\uff0c\u4ee5\u4fbf\u5728\u5c06\u6765\u518d\u6b21\u76d1\u542cZNode\u7684\u53d8\u5316\u3002<\/p>\n

            \u793a\u4f8b\u4ee3\u7801\uff08Java\uff09\uff1a<\/p>\n

            \/\/ \u521b\u5efaZooKeeper\u8fde\u63a5\nZooKeeper zooKeeper = new ZooKeeper("localhost:2181", 5000, null);\n\n\/\/ \u6ce8\u518cWatcher\uff0c\u76d1\u63a7ZNode\u7684\u6570\u636e\u53d8\u5316\nzooKeeper.getData("\/path\/to\/znode", event -> {\n    if (event.getType() == Watcher.Event.EventType.NodeDataChanged) {\n        \/\/ \u5904\u7406\u6570\u636e\u53d8\u5316\u4e8b\u4ef6\n        System.out.println("ZNode data changed!");\n    }\n}, null);\n<\/code><\/pre>\n
            \u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0cgetData()<\/code>\u65b9\u6cd5\u7528\u4e8e\u8bfb\u53d6ZNode\u7684\u6570\u636e\uff0c\u5e76\u5728ZNode\u7684\u6570\u636e\u53d1\u751f\u53d8\u5316\u65f6\u6ce8\u518cWatcher\u3002\u5728Watcher\u7684\u56de\u8c03\u51fd\u6570\u4e2d\uff0c\u5ba2\u6237\u7aef\u53ef\u4ee5\u5904\u7406ZNode\u6570\u636e\u53d8\u5316\u7684\u4e8b\u4ef6\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
            \u5728ZooKeeper\u4e2d\uff0c\u5ba2\u6237\u7aef\u6ce8\u518cWatcher\u662f\u901a\u8fc7\u5728\u8bfb\u53d6ZNode\u6570\u636e\u6216\u68c0\u6d4bZNode\u7684\u72b6\u6001\u65f6\u5411ZooKe […]<\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[124],"tags":[],"class_list":["post-15226","post","type-post","status-publish","format-standard","hentry","category-zookeeper"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15226","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=15226"}],"version-history":[{"count":2,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15226\/revisions"}],"predecessor-version":[{"id":48310,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/15226\/revisions\/48310"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=15226"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=15226"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=15226"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}