Examples with Request com.datastax.oss.driver.api.core.session.Request used on opensource projects

Example 1 with Request

use of com.datastax.oss.driver.api.core.session.Request in project java-driver by datastax.

the class ExecutionInfo method getSafePagingState.

/**
 * The paging state of the query, in a safe wrapper that checks if it's reused on the right
 * statement.
 *
 * <p>This represents the next page to be fetched if this query has multiple page of results. It
 * can be saved and reused later on the same statement.
 *
 * @return the paging state, or {@code null} if there is no next page.
 */
@Nullable
default PagingState getSafePagingState() {
    // Default implementation for backward compatibility, but we override it in the concrete class,
    // because it knows the attachment point.
    ByteBuffer rawPagingState = getPagingState();
    if (rawPagingState == null) {
        return null;
    } else {
        Request request = getRequest();
        if (!(request instanceof Statement)) {
            throw new IllegalStateException("Only statements should have a paging state");
        }
        Statement<?> statement = (Statement<?>) request;
        return new DefaultPagingState(rawPagingState, statement, AttachmentPoint.NONE);
    }
}

Example 2 with Request

use of com.datastax.oss.driver.api.core.session.Request in project java-driver by datastax.

the class BasicLoadBalancingPolicy method maybeAddDcFailover.

@NonNull
protected Queue<Node> maybeAddDcFailover(@Nullable Request request, @NonNull Queue<Node> local) {
    if (maxNodesPerRemoteDc <= 0 || localDc == null) {
        return local;
    }
    if (!allowDcFailoverForLocalCl && request instanceof Statement) {
        Statement<?> statement = (Statement<?>) request;
        ConsistencyLevel consistency = statement.getConsistencyLevel();
        if (consistency == null) {
            consistency = defaultConsistencyLevel;
        }
        if (consistency.isDcLocal()) {
            return local;
        }
    }
    QueryPlan remote = new LazyQueryPlan() {

        @Override
        protected Object[] computeNodes() {
            Object[] remoteNodes = liveNodes.dcs().stream().filter(Predicates.not(Predicates.equalTo(localDc))).flatMap(dc -> liveNodes.dc(dc).stream().limit(maxNodesPerRemoteDc)).toArray();
            int remoteNodesLength = remoteNodes.length;
            if (remoteNodesLength == 0) {
                return EMPTY_NODES;
            }
            shuffleHead(remoteNodes, remoteNodesLength);
            return remoteNodes;
        }
    };
    return new CompositeQueryPlan(local, remote);
}