循环遍历从 Hazelcast 的 ClientConfig 实例创建的 mapConfig 时出现 UnsupportedOperationException

Question

请问您如何循环遍历 mapConfig 以更改从 ClientConfig class 设置的运行 Hazelcast 的备份计数？

我已经检查了 hazelcast code examples 但在所有情况下，备份计数都是通过配置设置的我也尝试应用（顺便说一句，这是我自己问的）但我面临 UnsupportedOperationException 因为 Hazelcast ClientConfig 实例似乎无法在运行时更改，是否正确？ it/suggestion 是否有任何解决方法来克服它？

我有以下实现：

ClientConfig cfg = new ClientConfig();
if (hazelcastConfPath != null) {
    cfg = new XmlClientConfigBuilder(hazelcastConfPath).build();
}
cfg.setProperty("hazelcast.logging.type", "slf4j");
hazelcastInstance = HazelcastClient.newHazelcastClient(cfg);

int clusterSize = hazelcastInstance.getCluster().getMembers().size();
logger.info("Cluster size: {}", clusterSize);

for (Entry<String, MapConfig> currMap : hazelcastInstance.getConfig().getMapConfigs().entrySet()) {
    if (clusterSize - 1 > 1) {
        try {
            currMap.getValue().setBackupCount(clusterSize);

        } catch (Exception e) {
            logger.warn(e.getMessage(), e);
        }
    }

    logger.info("Map {} configured with {}", currMap.getKey(), currMap.getValue().getBackupCount());
}

和 Hazelcast XML 配置：

<?xml version="1.0" encoding="UTF-8"?>
<hazelcast ...>
    <network>
        <port auto-increment="false">${hazelcast.port}</port>
    </network>
    <management-center enabled="true" update-interval="3">
        ${hazelcast.mancenter.url}
    </management-center>
    <group>
        <name>${group.name}</name>
        <password>${group.password}</password>
    </group>
    <map name="*token">
        <max-idle-seconds>120</max-idle-seconds>
        <backup-count>1</backup-count>
        <eviction-policy>LRU</eviction-policy>
    </map>
    <map name="*actionSessionRedirUrlMap">
        <max-idle-seconds>30</max-idle-seconds>
        <backup-count>1</backup-count>
        <eviction-policy>LRU</eviction-policy>
    </map>
</hazelcast>

这样做，我遇到了 UnsupportedOperationException，这似乎是不可能的:'(

java.lang.UnsupportedOperationException: Client config object only supports adding new data structure configurations
at com.hazelcast.client.impl.clientside.ClientDynamicClusterConfig.getMapConfigs(ClientDynamicClusterConfig.java:591)
...

非常感谢，杰拉尔多·内托

Answer 1

您可以通过管理中心 (https://docs.hazelcast.org/docs/management-center/latest/manual/html/index.html#deploying-and-starting) 或通过使用名称相同但备份计数不同的新 MapConfig 启动精简会员来实现此目的。请参阅下面的示例：

MapConfig mapConfig = new MapConfig("map_a");
mapConfig.setBackupCount(3);

Config config = new Config();
config.setLiteMember(true);
config.addMapConfig(mapConfig);

HazelcastInstance lite = Hazelcast.newHazelcastInstance(config);

循环遍历从 Hazelcast 的 ClientConfig 实例创建的 mapConfig 时出现 UnsupportedOperationException

UnsupportedOperationException when looping over a mapConfig created from a ClientConfig instance of Hazelcast

hazelcast

hazelcast-imap

hazelcast-aggregate