| package org.apache.cassandra.db.transform; |
| |
| import java.util.Collections; |
| |
| import org.apache.cassandra.db.partitions.BasePartitionIterator; |
| import org.apache.cassandra.db.rows.BaseRowIterator; |
| import org.apache.cassandra.utils.Throwables; |
| |
| import static org.apache.cassandra.utils.Throwables.merge; |
| |
| public abstract class BasePartitions<R extends BaseRowIterator<?>, I extends BasePartitionIterator<? extends BaseRowIterator<?>>> |
| extends BaseIterator<BaseRowIterator<?>, I, R> |
| implements BasePartitionIterator<R> |
| { |
| |
| public BasePartitions(I input) |
| { |
| super(input); |
| } |
| |
| BasePartitions(BasePartitions<?, ? extends I> copyFrom) |
| { |
| super(copyFrom); |
| } |
| |
| |
| // ********************************* |
| |
| |
| protected BaseRowIterator<?> applyOne(BaseRowIterator<?> value, Transformation transformation) |
| { |
| return value == null ? null : transformation.applyToPartition(value); |
| } |
| |
| void add(Transformation transformation) |
| { |
| transformation.attachTo(this); |
| super.add(transformation); |
| next = applyOne(next, transformation); |
| } |
| |
| protected Throwable runOnClose(int length) |
| { |
| Throwable fail = null; |
| Transformation[] fs = stack; |
| for (int i = 0 ; i < length ; i++) |
| { |
| try |
| { |
| fs[i].onClose(); |
| } |
| catch (Throwable t) |
| { |
| fail = merge(fail, t); |
| } |
| } |
| return fail; |
| } |
| |
| public final boolean hasNext() |
| { |
| BaseRowIterator<?> next = null; |
| try |
| { |
| |
| Stop stop = this.stop; |
| while (this.next == null) |
| { |
| Transformation[] fs = stack; |
| int len = length; |
| |
| while (!stop.isSignalled && input.hasNext()) |
| { |
| next = input.next(); |
| for (int i = 0 ; next != null & i < len ; i++) |
| next = fs[i].applyToPartition(next); |
| |
| if (next != null) |
| { |
| this.next = next; |
| return true; |
| } |
| } |
| |
| if (stop.isSignalled || !hasMoreContents()) |
| return false; |
| } |
| return true; |
| |
| } |
| catch (Throwable t) |
| { |
| if (next != null) |
| Throwables.close(t, Collections.singleton(next)); |
| throw t; |
| } |
| } |
| |
| } |
| |