/*
* 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.flink.api.java.typeutils.runtime;
import com.esotericsoftware.kryo.KryoException;
import com.esotericsoftware.kryo.io.Input;
import java.io.IOException;
import java.io.InputStream;
public class NoFetchingInput extends Input {
public NoFetchingInput(InputStream inputStream){
super(inputStream, 8);
}
@Override
public boolean eof(){
throw new UnsupportedOperationException("NoFetchingInput does not support EOF.");
}
@Override
public int read() throws KryoException {
require(1);
return buffer[position++] & 0xFF;
}
@Override
public boolean canReadInt() throws KryoException {
throw new UnsupportedOperationException("NoFetchingInput cannot prefetch data.");
}
@Override
public boolean canReadLong() throws KryoException {
throw new UnsupportedOperationException("NoFetchingInput cannot prefetch data.");
}
/**
* Require makes sure that at least required number of bytes are kept in the buffer. If not, then
* it will load exactly the difference between required and currently available number of bytes.
* Thus, it will only load the data which is required and never prefetch data.
*
* @param required the number of bytes being available in the buffer
* @return the number of bytes remaining, which is equal to required
* @throws KryoException
*/
@Override
protected int require(int required) throws KryoException {
if(required > capacity) {
throw new KryoException("Buffer too small: capacity: " + capacity + ", " +
"required: " + required);
}
position = 0;
int bytesRead = 0;
int count;
while(true){
count = fill(buffer, bytesRead, required - bytesRead);
if(count == -1){
throw new KryoException("Buffer underflow");
}
bytesRead += count;
if(bytesRead == required){
break;
}
}
limit = required;
return required;
}
@Override
public int read(byte[] bytes, int offset, int count) throws KryoException {
if(bytes == null){
throw new IllegalArgumentException("bytes cannot be null.");
}
try {
return inputStream.read(bytes, offset, count);
}catch(IOException ex){
throw new KryoException(ex);
}
}
@Override
public void skip(int count) throws KryoException {
try{
inputStream.skip(count);
}catch(IOException ex){
throw new KryoException(ex);
}
}
@Override
public void readBytes(byte[] bytes, int offset, int count) throws KryoException {
if(bytes == null){
throw new IllegalArgumentException("bytes cannot be null.");
}
try{
int bytesRead = 0;
int c;
while(true){
c = inputStream.read(bytes, offset+bytesRead, count-bytesRead);
if(c == -1){
throw new KryoException("Buffer underflow");
}
bytesRead += c;
if(bytesRead == count){
break;
}
}
}catch(IOException ex){
throw new KryoException(ex);
}
}
}