com.datastax.driver.core.querybuilder

Class BuiltStatement

java.lang.Object

com.datastax.driver.core.Statement

com.datastax.driver.core.RegularStatement

com.datastax.driver.core.querybuilder.BuiltStatement

Direct Known Subclasses:

Batch, Batch.Options, Delete, Delete.Conditions, Delete.Options, Delete.Where, Insert, Insert.Options, Select, Select.Where, Truncate, Update, Update.Assignments, Update.Conditions, Update.Options, Update.Where

public abstract class BuiltStatement
extends RegularStatement

Common ancestor to the query builder built statements.

Field Summary

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

idempotent, NULL_PAYLOAD_VALUE

Method Summary

Modifier and Type	Method and Description
protected String	escapeId(String ident)
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.
boolean	hasValues() Whether or not this statement has values, that is if getValues will return null or not.
Boolean	isIdempotent() Whether this statement is idempotent, i.e.
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, getDefaultTimestamp, getFetchSize, getRetryPolicy, getSerialConsistencyLevel, isTracing, setConsistencyLevel, setDefaultTimestamp, setFetchSize, setIdempotent, setOutgoingPayload, setPagingState, setPagingStateUnsafe, setRetryPolicy, setSerialConsistencyLevel

Methods inherited from class java.lang.Object

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

Method Detail

escapeId

protected String escapeId(String ident)

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 return 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()

The values to use for this statement.

Note: Values for a RegularStatement (i.e. if this method does not return null) are not supported with the native protocol version 1: you will get an UnsupportedProtocolVersionException when submitting one if version 1 of the protocol is in use (i.e. if you've force version 1 through Cluster.Builder.withProtocolVersion(com.datastax.driver.core.ProtocolVersion) or you use Cassandra 1.2).

Note: Calling this method may trigger the underlying Cluster initialization.

Specified by:

getValues in class RegularStatement

See Also:

SimpleStatement.SimpleStatement(String, Cluster, Object...)

hasValues

public boolean hasValues()

Description copied from class: RegularStatement

Whether or not this statement has values, that is if getValues will return null or not.

Specified by:

hasValues in class RegularStatement

Returns:

false if RegularStatement.getValues() returns null, true otherwise.

isIdempotent

public Boolean isIdempotent()

Description copied from class: Statement

Whether this statement is idempotent, i.e. whether it can be applied multiple times without changing the result beyond the initial application.

Idempotence plays a role in speculative executions. If a statement is not idempotent, the driver will not schedule speculative executions for it.

Note that this method can return null, in which case the driver will default to QueryOptions.getDefaultIdempotence().

By default, this method returns null for all statements, except for BuiltStatements, where the value will be inferred from the query: if it updates counters, prepends/appends to a list, or uses a function call or QueryBuilder.raw(String) anywhere in an inserted value, the result will be false; otherwise it will be true. In all cases, calling Statement.setIdempotent(boolean) forces a value that overrides every other mechanism.

Overrides:

isIdempotent in class Statement

Returns:

whether this statement is idempotent, or null to use QueryOptions.getDefaultIdempotence().

toString

public String toString()

Note: Calling this method may trigger the underlying Cluster initialization.

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 unless the protocol version 1 is in use, see below) 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 guaranteed that getValues() will return null and that the string returned by getQueryString() will contain no other bind markers than the one inputted by the user.

If the native protocol version 1 is in use, the driver will default to not generating values since those are not supported by that version of the protocol. In practice, the driver will automatically call this method with true as argument prior to execution. Hence, calling this method when the protocol version 1 is in use is basically a no-op.

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.