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1   /*
2    * Copyright (c) 2011.  The Apache Software Foundation
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *     http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS,
16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17   * See the License for the specific language governing permissions and
18   * limitations under the License.
19   */
20  
21  package org.apache.hadoop.hbase.hbql.impl;
22  
23  import org.apache.hadoop.hbase.client.Result;
24  import org.apache.hadoop.hbase.hbql.client.HBqlException;
25  import org.apache.hadoop.hbase.hbql.statement.select.RowRequest;
26  import org.apache.hadoop.hbase.hbql.util.NullIterator;
27  
28  import java.util.Iterator;
29  import java.util.List;
30  
31  public class NonExecutorResultSet<T> extends HResultSetImpl<T, Object> {
32  
33      private final Iterator<RowRequest> rowRequestIterator;
34  
35      NonExecutorResultSet(final Query<T> query) throws HBqlException {
36          super(query, null);
37          this.rowRequestIterator = getQuery().getRowRequestList().iterator();
38      }
39  
40      private Iterator<RowRequest> getRowRequestIterator() {
41          return this.rowRequestIterator;
42      }
43  
44      protected void submitWork(final List<RowRequest> rowRequestList) {
45          // No op
46      }
47  
48      public Iterator<T> iterator() {
49  
50          try {
51              return new ResultSetIterator<T, Object>(this) {
52  
53                  protected boolean moreResultsPending() {
54                      return getRowRequestIterator().hasNext();
55                  }
56  
57                  protected Iterator<Result> getNextResultIterator() throws HBqlException {
58                      final RowRequest rowRequest = getRowRequestIterator().next();
59                      setCurrentResultScanner(rowRequest.getResultScanner(getMappingContext().getMapping(),
60                                                                          getWithArgs(),
61                                                                          getTableWrapper().getHTable()));
62                      return getCurrentResultScanner().iterator();
63                  }
64              };
65          }
66          catch (HBqlException e) {
67              e.printStackTrace();
68              getQuery().callOnException(e);
69              return new NullIterator<T>();
70          }
71      }
72  }
73  
74