Java tutorial
/** * 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.hadoop.mapreduce.lib.db; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.mapreduce.InputSplit; /** * Implement DBSplitter over boolean values. */ @InterfaceAudience.Public @InterfaceStability.Evolving public class BooleanSplitter implements DBSplitter { public List<InputSplit> split(Configuration conf, ResultSet results, String colName) throws SQLException { List<InputSplit> splits = new ArrayList<InputSplit>(); if (results.getString(1) == null && results.getString(2) == null) { // Range is null to null. Return a null split accordingly. splits.add( new DataDrivenDBInputFormat.DataDrivenDBInputSplit(colName + " IS NULL", colName + " IS NULL")); return splits; } boolean minVal = results.getBoolean(1); boolean maxVal = results.getBoolean(2); // Use one or two splits. if (!minVal) { splits.add( new DataDrivenDBInputFormat.DataDrivenDBInputSplit(colName + " = FALSE", colName + " = FALSE")); } if (maxVal) { splits.add( new DataDrivenDBInputFormat.DataDrivenDBInputSplit(colName + " = TRUE", colName + " = TRUE")); } if (results.getString(1) == null || results.getString(2) == null) { // Include a null value. splits.add( new DataDrivenDBInputFormat.DataDrivenDBInputSplit(colName + " IS NULL", colName + " IS NULL")); } return splits; } }