| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more contributor license |
| * agreements. See the NOTICE file distributed with this work for additional information regarding |
| * copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the License. You may obtain a |
| * copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software distributed under the License |
| * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express |
| * or implied. See the License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| |
| package org.apache.fluo.core.impl.scanner; |
| |
| import java.util.Iterator; |
| import java.util.Map.Entry; |
| import java.util.function.Function; |
| |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.Iterators; |
| import com.google.common.collect.PeekingIterator; |
| import org.apache.accumulo.core.data.Key; |
| import org.apache.accumulo.core.data.Value; |
| import org.apache.fluo.api.client.scanner.ColumnScanner; |
| import org.apache.fluo.api.data.Bytes; |
| import org.apache.fluo.api.data.Column; |
| import org.apache.fluo.api.data.ColumnValue; |
| import org.apache.fluo.core.util.ByteUtil; |
| |
| public class ColumnScannerImpl implements ColumnScanner { |
| |
| public ColumnValue entry2cv(Entry<Key, Value> entry) { |
| Column col = columnConverter.apply(entry.getKey()); |
| Bytes val = Bytes.of(entry.getValue().get()); |
| return new ColumnValue(col, val); |
| } |
| |
| private PeekingIterator<Entry<Key, Value>> peekingIter; |
| private Bytes row; |
| private Iterator<ColumnValue> iter; |
| private boolean gotIter = false; |
| private Function<Key, Column> columnConverter; |
| |
| ColumnScannerImpl(Iterator<Entry<Key, Value>> e, Function<Key, Column> columnConverter) { |
| peekingIter = Iterators.peekingIterator(e); |
| this.columnConverter = columnConverter; |
| row = ByteUtil.toBytes(peekingIter.peek().getKey().getRowData()); |
| iter = Iterators.transform(peekingIter, this::entry2cv); |
| } |
| |
| @Override |
| public Iterator<ColumnValue> iterator() { |
| Preconditions.checkState(!gotIter, |
| "Unfortunately this implementation only support getting the iterator once"); |
| gotIter = true; |
| return iter; |
| } |
| |
| @Override |
| public Bytes getRow() { |
| return row; |
| } |
| |
| @Override |
| public String getsRow() { |
| return getRow().toString(); |
| } |
| } |