Class QueryHandler

java.lang.Object

com.loomcache.server.handler.QueryHandler

public class QueryHandler
extends Object

Handles SQL query operations over the network. Routes queries to the QueryEngine for execution against distributed maps.

Supported Operations:

• SQL_QUERY_EXECUTE — execute a parameterized query against a map

Message Format:

• mapName — target map name to query
• key — serialized QueryPlan object
• value — (optional) query parameters

Response Format: The response value contains serialized SqlResult containing:

• Column names
• Column types
• Result rows

Since:

1.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	QueryHandler.SqlCatalogAuthorization

Constructor Summary

Constructors

Constructor	Description
QueryHandler(DataStructureRegistry dataStructureRegistry, int instanceNumber)	Create a query handler.

Method Summary

Modifier and Type	Method	Description
@Nullable Message	handle(Message msg)	Handle a SQL query operation message.
@Nullable Message	handle(Message msg, QueryHandler.SqlCatalogAuthorization sqlCatalogAuthorization)
void	setCrossGroupQueryExecutor(@Nullable CrossGroupQueryExecutor executor)	Install a CrossGroupQueryExecutor so SQL queries fan out across every Raft group when sharding is enabled.
void	setLoomMetrics(@Nullable LoomMetrics metrics)
void	setMutationLock(@Nullable ReentrantLock lock)
void	setNearCacheInvalidationManager(@Nullable NearCacheInvalidationManager manager)
void	setTransactionKeyLockManager(@Nullable TransactionKeyLockManager lockManager)
Optional<String>	validateMutationAuthorization(Message msg, QueryHandler.SqlCatalogAuthorization sqlCatalogAuthorization)

Methods inherited from class Object

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

Constructor Details

QueryHandler

public QueryHandler(DataStructureRegistry dataStructureRegistry,
 int instanceNumber)

Create a query handler.

Parameters:

dataStructureRegistry - the registry containing distributed structures (non-null)

instanceNumber - the node instance number for logging (non-negative)

Throws:

NullPointerException - if dataStructureRegistry is null

Method Details

setCrossGroupQueryExecutor

public void setCrossGroupQueryExecutor(@Nullable CrossGroupQueryExecutor executor)

Install a CrossGroupQueryExecutor so SQL queries fan out across every Raft group when sharding is enabled. Passing null reverts to single-registry execution.

Parameters:

executor - the cross-group executor, or null to disable cross-group fan-out

setLoomMetrics

public void setLoomMetrics(@Nullable LoomMetrics metrics)

setNearCacheInvalidationManager

public void setNearCacheInvalidationManager(@Nullable NearCacheInvalidationManager manager)

setTransactionKeyLockManager

public void setTransactionKeyLockManager(@Nullable TransactionKeyLockManager lockManager)

setMutationLock

public void setMutationLock(@Nullable ReentrantLock lock)

handle

public @Nullable Message handle(Message msg)

Handle a SQL query operation message.

Parameters:

msg - the incoming message (non-null)

Returns:

a response message with the query result, or null if msg is null

Throws:

NullPointerException - if msg is null

handle

public @Nullable Message handle(Message msg,
 QueryHandler.SqlCatalogAuthorization sqlCatalogAuthorization)

validateMutationAuthorization

public Optional<String> validateMutationAuthorization(Message msg,
 QueryHandler.SqlCatalogAuthorization sqlCatalogAuthorization)