/**
* 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.typedbytes;
import java.io.DataInput;
import java.io.EOFException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.TreeMap;
import org.apache.hadoop.io.WritableUtils;
import org.apache.hadoop.record.Buffer;
/**
* Provides functionality for reading typed bytes.
*/
public class TypedBytesInput {
private DataInput in;
private TypedBytesInput() {}
private void setDataInput(DataInput in) {
this.in = in;
}
private static ThreadLocal tbIn = new ThreadLocal() {
protected synchronized Object initialValue() {
return new TypedBytesInput();
}
};
/**
* Get a thread-local typed bytes input for the supplied {@link DataInput}.
* @param in data input object
* @return typed bytes input corresponding to the supplied {@link DataInput}.
*/
public static TypedBytesInput get(DataInput in) {
TypedBytesInput bin = (TypedBytesInput) tbIn.get();
bin.setDataInput(in);
return bin;
}
/** Creates a new instance of TypedBytesInput. */
public TypedBytesInput(DataInput in) {
this.in = in;
}
/**
* Reads a typed bytes sequence and converts it to a Java object. The first
* byte is interpreted as a type code, and then the right number of
* subsequent bytes are read depending on the obtained type.
* @return the obtained object or null when the end of the file is reached
* @throws IOException
*/
public Object read() throws IOException {
int code = 1;
try {
code = in.readUnsignedByte();
} catch (EOFException eof) {
return null;
}
if (code == Type.BYTES.code) {
return new Buffer(readBytes());
} else if (code == Type.BYTE.code) {
return readByte();
} else if (code == Type.BOOL.code) {
return readBool();
} else if (code == Type.INT.code) {
return readInt();
} else if (code == Type.LONG.code) {
return readLong();
} else if (code == Type.FLOAT.code) {
return readFloat();
} else if (code == Type.DOUBLE.code) {
return readDouble();
} else if (code == Type.STRING.code) {
return readString();
} else if (code == Type.VECTOR.code) {
return readVector();
} else if (code == Type.LIST.code) {
return readList();
} else if (code == Type.MAP.code) {
return readMap();
} else if (code == Type.MARKER.code) {
return null;
} else if (50 <= code && code <= 200) { // application-specific typecodes
return new Buffer(readBytes());
} else {
throw new RuntimeException("unknown type");
}
}
/**
* Reads a typed bytes sequence. The first byte is interpreted as a type code,
* and then the right number of subsequent bytes are read depending on the
* obtained type.
*
* @return the obtained typed bytes sequence or null when the end of the file
* is reached
* @throws IOException
*/
public byte[] readRaw() throws IOException {
int code = -1;
try {
code = in.readUnsignedByte();
} catch (EOFException eof) {
return null;
}
if (code == Type.BYTES.code) {
return readRawBytes();
} else if (code == Type.BYTE.code) {
return readRawByte();
} else if (code == Type.BOOL.code) {
return readRawBool();
} else if (code == Type.INT.code) {
return readRawInt();
} else if (code == Type.LONG.code) {
return readRawLong();
} else if (code == Type.FLOAT.code) {
return readRawFloat();
} else if (code == Type.DOUBLE.code) {
return readRawDouble();
} else if (code == Type.STRING.code) {
return readRawString();
} else if (code == Type.VECTOR.code) {
return readRawVector();
} else if (code == Type.LIST.code) {
return readRawList();
} else if (code == Type.MAP.code) {
return readRawMap();
} else if (code == Type.MARKER.code) {
return null;
} else if (50 <= code && code <= 200) { // application-specific typecodes
return readRawBytes(code);
} else {
throw new RuntimeException("unknown type");
}
}
/**
* Reads a type byte and returns the corresponding {@link Type}.
* @return the obtained Type or null when the end of the file is reached
* @throws IOException
*/
public Type readType() throws IOException {
int code = -1;
try {
code = in.readUnsignedByte();
} catch (EOFException eof) {
return null;
}
for (Type type : Type.values()) {
if (type.code == code) {
return type;
}
}
return null;
}
/**
* Skips a type byte.
* @return true iff the end of the file was not reached
* @throws IOException
*/
public boolean skipType() throws IOException {
try {
in.readByte();
return true;
} catch (EOFException eof) {
return false;
}
}
/**
* Reads the bytes following a <code>Type.BYTES</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readBytes() throws IOException {
int length = in.readInt();
byte[] bytes = new byte[length];
in.readFully(bytes);
return bytes;
}
/**
* Reads the raw bytes following a custom code.
* @param code the custom type code
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawBytes(int code) throws IOException {
int length = in.readInt();
byte[] bytes = new byte[5 + length];
bytes[0] = (byte) code;
bytes[1] = (byte) (0xff & (length >> 24));
bytes[2] = (byte) (0xff & (length >> 16));
bytes[3] = (byte) (0xff & (length >> 8));
bytes[4] = (byte) (0xff & length);
in.readFully(bytes, 5, length);
return bytes;
}
/**
* Reads the raw bytes following a <code>Type.BYTES</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawBytes() throws IOException {
return readRawBytes(Type.BYTES.code);
}
/**
* Reads the byte following a <code>Type.BYTE</code> code.
* @return the obtained byte
* @throws IOException
*/
public byte readByte() throws IOException {
return in.readByte();
}
/**
* Reads the raw byte following a <code>Type.BYTE</code> code.
* @return the obtained byte
* @throws IOException
*/
public byte[] readRawByte() throws IOException {
byte[] bytes = new byte[2];
bytes[0] = (byte) Type.BYTE.code;
in.readFully(bytes, 1, 1);
return bytes;
}
/**
* Reads the boolean following a <code>Type.BOOL</code> code.
* @return the obtained boolean
* @throws IOException
*/
public boolean readBool() throws IOException {
return in.readBoolean();
}
/**
* Reads the raw bytes following a <code>Type.BOOL</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawBool() throws IOException {
byte[] bytes = new byte[2];
bytes[0] = (byte) Type.BOOL.code;
in.readFully(bytes, 1, 1);
return bytes;
}
/**
* Reads the integer following a <code>Type.INT</code> code.
* @return the obtained integer
* @throws IOException
*/
public int readInt() throws IOException {
return in.readInt();
}
/**
* Reads the raw bytes following a <code>Type.INT</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawInt() throws IOException {
byte[] bytes = new byte[5];
bytes[0] = (byte) Type.INT.code;
in.readFully(bytes, 1, 4);
return bytes;
}
/**
* Reads the long following a <code>Type.LONG</code> code.
* @return the obtained long
* @throws IOException
*/
public long readLong() throws IOException {
return in.readLong();
}
/**
* Reads the raw bytes following a <code>Type.LONG</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawLong() throws IOException {
byte[] bytes = new byte[9];
bytes[0] = (byte) Type.LONG.code;
in.readFully(bytes, 1, 8);
return bytes;
}
/**
* Reads the float following a <code>Type.FLOAT</code> code.
* @return the obtained float
* @throws IOException
*/
public float readFloat() throws IOException {
return in.readFloat();
}
/**
* Reads the raw bytes following a <code>Type.FLOAT</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawFloat() throws IOException {
byte[] bytes = new byte[5];
bytes[0] = (byte) Type.FLOAT.code;
in.readFully(bytes, 1, 4);
return bytes;
}
/**
* Reads the double following a <code>Type.DOUBLE</code> code.
* @return the obtained double
* @throws IOException
*/
public double readDouble() throws IOException {
return in.readDouble();
}
/**
* Reads the raw bytes following a <code>Type.DOUBLE</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawDouble() throws IOException {
byte[] bytes = new byte[9];
bytes[0] = (byte) Type.DOUBLE.code;
in.readFully(bytes, 1, 8);
return bytes;
}
/**
* Reads the string following a <code>Type.STRING</code> code.
* @return the obtained string
* @throws IOException
*/
public String readString() throws IOException {
return WritableUtils.readString(in);
}
/**
* Reads the raw bytes following a <code>Type.STRING</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawString() throws IOException {
int length = in.readInt();
byte[] bytes = new byte[5 + length];
bytes[0] = (byte) Type.STRING.code;
bytes[1] = (byte) (0xff & (length >> 24));
bytes[2] = (byte) (0xff & (length >> 16));
bytes[3] = (byte) (0xff & (length >> 8));
bytes[4] = (byte) (0xff & length);
in.readFully(bytes, 5, length);
return bytes;
}
/**
* Reads the vector following a <code>Type.VECTOR</code> code.
* @return the obtained vector
* @throws IOException
*/
@SuppressWarnings("unchecked")
public ArrayList readVector() throws IOException {
int length = readVectorHeader();
ArrayList result = new ArrayList(length);
for (int i = 0; i < length; i++) {
result.add(read());
}
return result;
}
/**
* Reads the raw bytes following a <code>Type.VECTOR</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawVector() throws IOException {
Buffer buffer = new Buffer();
int length = readVectorHeader();
buffer.append(new byte[] {
(byte) Type.VECTOR.code,
(byte) (0xff & (length >> 24)), (byte) (0xff & (length >> 16)),
(byte) (0xff & (length >> 8)), (byte) (0xff & length)
});
for (int i = 0; i < length; i++) {
buffer.append(readRaw());
}
return buffer.get();
}
/**
* Reads the header following a <code>Type.VECTOR</code> code.
* @return the number of elements in the vector
* @throws IOException
*/
public int readVectorHeader() throws IOException {
return in.readInt();
}
/**
* Reads the list following a <code>Type.LIST</code> code.
* @return the obtained list
* @throws IOException
*/
@SuppressWarnings("unchecked")
public List readList() throws IOException {
List list = new ArrayList();
Object obj = read();
while (obj != null) {
list.add(obj);
obj = read();
}
return list;
}
/**
* Reads the raw bytes following a <code>Type.LIST</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawList() throws IOException {
Buffer buffer = new Buffer(new byte[] { (byte) Type.LIST.code });
byte[] bytes = readRaw();
while (bytes != null) {
buffer.append(bytes);
bytes = readRaw();
}
buffer.append(new byte[] { (byte) Type.MARKER.code });
return buffer.get();
}
/**
* Reads the map following a <code>Type.MAP</code> code.
* @return the obtained map
* @throws IOException
*/
@SuppressWarnings("unchecked")
public TreeMap readMap() throws IOException {
int length = readMapHeader();
TreeMap result = new TreeMap();
for (int i = 0; i < length; i++) {
Object key = read();
Object value = read();
result.put(key, value);
}
return result;
}
/**
* Reads the raw bytes following a <code>Type.MAP</code> code.
* @return the obtained bytes sequence
* @throws IOException
*/
public byte[] readRawMap() throws IOException {
Buffer buffer = new Buffer();
int length = readMapHeader();
buffer.append(new byte[] {
(byte) Type.MAP.code,
(byte) (0xff & (length >> 24)), (byte) (0xff & (length >> 16)),
(byte) (0xff & (length >> 8)), (byte) (0xff & length)
});
for (int i = 0; i < length; i++) {
buffer.append(readRaw());
buffer.append(readRaw());
}
return buffer.get();
}
/**
* Reads the header following a <code>Type.MAP</code> code.
* @return the number of key-value pairs in the map
* @throws IOException
*/
public int readMapHeader() throws IOException {
return in.readInt();
}
}