com.datastax.driver.core.querybuilder

Class Truncate

java.lang.Object

com.datastax.driver.core.Statement

com.datastax.driver.core.RegularStatement

com.datastax.driver.core.querybuilder.Truncate

public class Truncate
extends RegularStatement

A built TRUNCATE statement.

Method Summary

Methods

Modifier and Type	Method and Description
protected StringBuilder	buildQueryString(List<ByteBuffer> variables)
String	getKeyspace() Returns the keyspace this query operates on.
String	getQueryString() Returns the query string for this statement.
ByteBuffer	getRoutingKey() Returns the routing key (in binary raw form) to use for token aware routing of this query.
ByteBuffer[]	getValues() The values to use for this statement.
RegularStatement	setForceNoValues(boolean forceNoValues) Allows to force this builder to not generate values (through its getValues() method).
String	toString()

Methods inherited from class com.datastax.driver.core.Statement

disableTracing, enableTracing, getConsistencyLevel, getFetchSize, getRetryPolicy, getSerialConsistencyLevel, isTracing, setConsistencyLevel, setFetchSize, setRetryPolicy, setSerialConsistencyLevel

Methods inherited from class java.lang.Object

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

Method Detail

buildQueryString

protected StringBuilder buildQueryString(List<ByteBuffer> variables)

getQueryString

public String getQueryString()

Description copied from class: RegularStatement

Returns the query string for this statement.

Specified by:

getQueryString in class RegularStatement

Returns:

a valid CQL query string.

getRoutingKey

public ByteBuffer getRoutingKey()

Description copied from class: Statement

Returns the routing key (in binary raw form) to use for token aware routing of this query.

The routing key is optional in that implementers are free to return null. The routing key is an hint used for token-aware routing (see TokenAwarePolicy), and if provided should correspond to the binary value for the query partition key. However, not providing a routing key never causes a query to fail and if the load balancing policy used is not token aware, then the routing key can be safely ignored.

Specified by:

getRoutingKey in class Statement

Returns:

the routing key for this query or null.

getKeyspace

public String getKeyspace()

Description copied from class: Statement

Returns the keyspace this query operates on.

Note that not all query specify on which keyspace they operate on, and so this method can always reutrn null. Firstly, some queries do not operate inside a keyspace: keyspace creation, USE queries, user creation, etc. Secondly, even query that operate within a keyspace do not have to specify said keyspace directly, in which case the currently logged in keyspace (the one set through a USE query (or through the use of Cluster.connect(String))). Lastly, as for the routing key, this keyspace information is only a hint for token-aware routing (since replica placement depend on the replication strategy in use which is a per-keyspace property) and having this method return null (or even a bogus keyspace name) will never cause the query to fail.

Specified by:

getKeyspace in class Statement

Returns:

the keyspace this query operate on if relevant or null.

getValues

public ByteBuffer[] getValues()

Description copied from class: RegularStatement

The values to use for this statement.

Specified by:

getValues in class RegularStatement

Returns:

the values to use for this statement or null if there is no such values.

See Also:

SimpleStatement.SimpleStatement(String, Object...)

toString

public String toString()

Overrides:

toString in class RegularStatement

setForceNoValues

public RegularStatement setForceNoValues(boolean forceNoValues)

Allows to force this builder to not generate values (through its getValues() method).

By default and for performance reasons, the query builder will not serialize all values provided to strings. This means that the getQueryString() may return a query string with bind markers (where and when is at the discretion of the builder) and getValues() will return the binary values for those markers. This method allows to force the builder to not generate binary values but rather to serialize them all in the query string. In practice, this means that if you call setForceNoValues(true), you are guarateed that getValues() will return null and that the string returned by getQueryString() will contain no other bind markers than the one inputed by the user.

Note that this method is mainly useful for debugging purpose. In general, the default behavior should be the correct and most efficient one.

Parameters:

forceNoValues - whether or not this builder may generate values.

Returns:

this statement.