Zookeeper::exists
(PECL zookeeper >= 0.1.0)
Zookeeper::exists — Checks the existence of a node in zookeeper synchronously.
説明
パラメータ
-
path -
The name of the node. Expressed as a file name with slashes separating ancestors of the node.
-
watcher_cb -
if nonzero, a watch will be set at the server to notify the client if the node changes. The watch will be set even if the node does not
返り値
Returns true/false on success, and false on failure.
エラー / 例外
This method emits PHP error/warning when parameters count or types are wrong or fail to check the existence of a node.
警告
Since version 0.3.0, this method emits ZookeeperException and it's derivatives.
例
例1 Zookeeper::exists() example
Check the existence of a node.
<?php
$zookeeper = new Zookeeper('locahost:2181');
$path = '/path/to/node';
$r = $zookeeper->exists($path);
if ($r)
echo 'EXISTS';
else
echo 'N/A or ERR';
?>
上の例の出力は以下となります。
EXISTS
参考
- Zookeeper::get() - Gets the data associated with a node synchronously.
- ZookeeperException
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