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https://issues.apache.org/jira/browse/CASSANDRA-7299?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14039167#comment-14039167
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Robert Stupp commented on CASSANDRA-7299:
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[~alexander_radzin] You're posting in the wrong JIRA. What you describe belongs
to the Java driver (client) and not Cassandra (server). The JIRA you're looking
for is at https://datastax-oss.atlassian.net/browse/JAVA
> Cluster.Builder throws UnknownHostException when adding not existing host
> -------------------------------------------------------------------------
>
> Key: CASSANDRA-7299
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7299
> Project: Cassandra
> Issue Type: Bug
> Components: API
> Reporter: Alexander Radzin
> Priority: Trivial
>
> Connection to Cassandra cluster from client side is typically done using
> {{Cluster.Builder}} class that allows to configure the connection and then
> build cluster by invocation of method {{build()}}. Not all contact points
> must be available at creation time. If some of them start after the
> connection has been established they client continue its work using the newly
> connected endpoints.
> However if specific hostname is not available at the moment when builder is
> being created {{UnknownHostException}} is thrown.
> IMHO Typically applications tend to create builder on start-up when reading
> configuration parameters and then connect to Cassandra. For example in Spring
> based applications this happens during context creation.
> This issue prevents the application to start.
> This does not happen when using IP address even if it is not available at the
> moment.
> The problem is that {{Builder.addContactPoint()}} invokes
> {{InetAddress.getByName()}} when creating the builder.
> {noformat}
> public Builder addContactPoint(String address) {
> try {
> this.addresses.add(InetAddress.getByName(address));
> return this;
> } catch (UnknownHostException e) {
> throw new IllegalArgumentException(e.getMessage());
> }
> }
> {noformat}
> IMHO it should do this only when building the cluster.
> My current work around is to extend {{Cluster.Builder}} (fortunately it is
> public and not final) and store addresses in their textual for transforming
> the to instances of {{InetAddress}} only when {{build()}} is called. This is
> however not full solution because the {{Cluster}} itself also requires list
> of {{InetAddress}}.
> The point here is that we can create builder and cluster with unavailable
> contact points if string representation of IP address is supplied but cannot
> use symbolic computer name. This is because {{InetAddress.getByName()}}
> throws {{UnknownHostException}} only if host identified by name is not
> available:
> {quote}
> If a literal IP address is supplied, only the validity of the address format
> is checked.
> {quote}
> (from Javadoc of {{InetAddress.getByName()}}.
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