/**
* 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.hcatalog.data;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.apache.hadoop.io.VIntWritable;
import org.apache.hadoop.io.VLongWritable;
public abstract class ReaderWriter {
private static final String UTF8 = "UTF-8";
public static Object readDatum(DataInput in) throws IOException {
byte type = in.readByte();
switch (type) {
case DataType.STRING:
byte[] buffer = new byte[in.readInt()];
in.readFully(buffer);
return new String(buffer, UTF8);
case DataType.INTEGER:
VIntWritable vint = new VIntWritable();
vint.readFields(in);
return vint.get();
case DataType.LONG:
VLongWritable vlong = new VLongWritable();
vlong.readFields(in);
return vlong.get();
case DataType.FLOAT:
return in.readFloat();
case DataType.DOUBLE:
return in.readDouble();
case DataType.BOOLEAN:
return in.readBoolean();
case DataType.BYTE:
return in.readByte();
case DataType.SHORT:
return in.readShort();
case DataType.NULL:
return null;
case DataType.BINARY:
int len = in.readInt();
byte[] ba = new byte[len];
in.readFully(ba);
return ba;
case DataType.MAP:
int size = in.readInt();
Map<Object, Object> m = new HashMap<Object, Object>(size);
for (int i = 0; i < size; i++) {
m.put(readDatum(in), readDatum(in));
}
return m;
case DataType.LIST:
int sz = in.readInt();
List<Object> list = new ArrayList<Object>(sz);
for (int i = 0; i < sz; i++) {
list.add(readDatum(in));
}
return list;
default:
throw new IOException("Unexpected data type " + type +
" found in stream.");
}
}
public static void writeDatum(DataOutput out, Object val) throws IOException {
// write the data type
byte type = DataType.findType(val);
switch (type) {
case DataType.LIST:
out.writeByte(DataType.LIST);
List<?> list = (List<?>) val;
int sz = list.size();
out.writeInt(sz);
for (int i = 0; i < sz; i++) {
writeDatum(out, list.get(i));
}
return;
case DataType.MAP:
out.writeByte(DataType.MAP);
Map<?, ?> m = (Map<?, ?>) val;
out.writeInt(m.size());
Iterator<?> i =
m.entrySet().iterator();
while (i.hasNext()) {
Entry<?, ?> entry = (Entry<?, ?>) i.next();
writeDatum(out, entry.getKey());
writeDatum(out, entry.getValue());
}
return;
case DataType.INTEGER:
out.writeByte(DataType.INTEGER);
new VIntWritable((Integer) val).write(out);
return;
case DataType.LONG:
out.writeByte(DataType.LONG);
new VLongWritable((Long) val).write(out);
return;
case DataType.FLOAT:
out.writeByte(DataType.FLOAT);
out.writeFloat((Float) val);
return;
case DataType.DOUBLE:
out.writeByte(DataType.DOUBLE);
out.writeDouble((Double) val);
return;
case DataType.BOOLEAN:
out.writeByte(DataType.BOOLEAN);
out.writeBoolean((Boolean) val);
return;
case DataType.BYTE:
out.writeByte(DataType.BYTE);
out.writeByte((Byte) val);
return;
case DataType.SHORT:
out.writeByte(DataType.SHORT);
out.writeShort((Short) val);
return;
case DataType.STRING:
String s = (String) val;
byte[] utfBytes = s.getBytes(ReaderWriter.UTF8);
out.writeByte(DataType.STRING);
out.writeInt(utfBytes.length);
out.write(utfBytes);
return;
case DataType.BINARY:
byte[] ba = (byte[]) val;
out.writeByte(DataType.BINARY);
out.writeInt(ba.length);
out.write(ba);
return;
case DataType.NULL:
out.writeByte(DataType.NULL);
return;
default:
throw new IOException("Unexpected data type " + type +
" found in stream.");
}
}
}