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.gora.util; import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; import java.util.Map.Entry; import java.util.Properties; import org.apache.hadoop.io.MapWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.io.Writable; /** * An utility class for {@link Writable} related functionality. */ public class WritableUtils { private WritableUtils() { // prevents instantiation } public static final void writeProperties(DataOutput out, Properties props) throws IOException { MapWritable propsWritable = new MapWritable(); for (Entry<Object, Object> prop : props.entrySet()) { Writable key = new Text(prop.getKey().toString()); Writable value = new Text(prop.getValue().toString()); propsWritable.put(key, value); } propsWritable.write(out); } public static final Properties readProperties(DataInput in) throws IOException { Properties props = new Properties(); MapWritable propsWritable = new MapWritable(); propsWritable.readFields(in); for (Entry<Writable, Writable> prop : propsWritable.entrySet()) { String key = prop.getKey().toString(); String value = prop.getValue().toString(); props.put(key, value); } return props; } }