Package com.datastax.driver.core.exceptions

Class NoHostAvailableException

java.lang.Object

java.lang.Throwable

java.lang.Exception

java.lang.RuntimeException

com.datastax.driver.core.exceptions.DriverException

com.datastax.driver.core.exceptions.NoHostAvailableException

All Implemented Interfaces:

Serializable

public class NoHostAvailableException
extends DriverException

Exception thrown when a query cannot be performed because no host is available.

This exception is thrown if either:

• there is no host live in the cluster at the moment of the query;
• all hosts that have been tried have failed.

For debugging purposes, the list of hosts that have been tried along with the failure cause can be retrieved using the getErrors() method.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
NoHostAvailableException(Map<EndPoint,Throwable> errors)

Method Summary

Modifier and Type	Method	Description
NoHostAvailableException	copy()	Copy the exception.
String	getCustomMessage(int maxErrors, boolean formatted, boolean includeStackTraces)	Builds a custom message for this exception.
Map<EndPoint,Throwable>	getErrors()	Return the hosts tried along with the error encountered while trying them.

Methods inherited from class java.lang.Throwable

addSuppressed, fillInStackTrace, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

NoHostAvailableException

public NoHostAvailableException(Map<EndPoint,Throwable> errors)

Method Detail

getErrors

public Map<EndPoint,Throwable> getErrors()

Return the hosts tried along with the error encountered while trying them.

Returns:

a map containing for each tried host the error triggered when trying it.

getCustomMessage

public String getCustomMessage(int maxErrors,
                               boolean formatted,
                               boolean includeStackTraces)

Builds a custom message for this exception.

Parameters:

maxErrors - the maximum number of errors displayed (useful to limit the size of the message for big clusters). Beyond this limit, host names are still displayed, but not the associated errors. Set to Integer.MAX_VALUE to display all hosts.

formatted - whether to format the output (line break between each host).

includeStackTraces - whether to include the full stacktrace of each host error. Note that this automatically implies formatted.

Returns:

the message.

copy

public NoHostAvailableException copy()

Description copied from class: DriverException

Copy the exception.

This returns a new exception, equivalent to the original one, except that because a new object is created in the current thread, the top-most element in the stacktrace of the exception will refer to the current thread (this is mainly intended for internal use by the driver). The cause of the copied exception will be the original exception.

Overrides:

copy in class DriverException

Returns:

a copy/clone of this exception.