| /* |
| * 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.ignite.internal.processors.cache.persistence.wal.io; |
| |
| import java.io.EOFException; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import org.apache.ignite.internal.processors.cache.persistence.file.FileIO; |
| import org.apache.ignite.internal.processors.cache.persistence.wal.ByteBufferExpander; |
| import org.jetbrains.annotations.NotNull; |
| |
| /** |
| * File input, backed by byte buffer file input. |
| * This class allows to read data by chunks from file and then read primitives |
| */ |
| public class SimpleFileInput implements FileInput { |
| /** |
| * Buffer for reading blocks of data into. |
| * <b>Note:</b> biggest block requested from this input can't be longer than buffer capacity |
| */ |
| private ByteBuffer buf; |
| |
| /** I/O interface for read/write operations with file */ |
| protected FileIO io; |
| |
| /** */ |
| private long pos; |
| |
| /** */ |
| private ByteBufferExpander expBuf; |
| |
| /** |
| * @param io FileIO to read from. |
| * @param buf Buffer for reading blocks of data into. |
| */ |
| public SimpleFileInput(FileIO io, ByteBufferExpander buf) throws IOException { |
| assert io != null; |
| |
| this.io = io; |
| this.buf = buf.buffer(); |
| |
| expBuf = buf; |
| |
| pos = io.position(); |
| |
| clearBuffer(); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override public FileIO io() { |
| return io; |
| } |
| |
| /** |
| * Clear buffer. |
| */ |
| private void clearBuffer() { |
| buf.clear(); |
| buf.limit(0); |
| |
| assert buf.remaining() == 0; // Buffer is empty. |
| } |
| |
| /** {@inheritDoc} */ |
| @Override public void seek(long pos) throws IOException { |
| if (pos > io.size()) |
| throw new EOFException(); |
| |
| io.position(pos); |
| |
| this.pos = pos; |
| |
| clearBuffer(); |
| } |
| |
| /** |
| * @return Underlying buffer. |
| */ |
| @Override public ByteBuffer buffer() { |
| return buf; |
| } |
| |
| |
| /** {@inheritDoc} */ |
| @Override public void ensure(int requested) throws IOException { |
| int available = buf.remaining(); |
| |
| if (available >= requested) |
| return; |
| |
| if (buf.capacity() < requested) { |
| if (expBuf == null) |
| throw new IOException("Requested size is greater than buffer: " + requested); |
| |
| buf = expBuf.expand(requested); |
| |
| assert available == buf.remaining(); |
| } |
| |
| buf.compact(); |
| |
| do { |
| int read = io.read(buf); |
| |
| if (read == -1) |
| throw new EOFException("EOF at position [" + io.position() + "] expected to read [" + requested + "] bytes"); |
| |
| available += read; |
| |
| pos += read; |
| } |
| while (available < requested); |
| |
| buf.flip(); |
| } |
| |
| /** |
| * @return Position in the stream. |
| */ |
| @Override public long position() { |
| return pos - buf.remaining(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public void readFully(@NotNull byte[] b) throws IOException { |
| ensure(b.length); |
| |
| buf.get(b); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public void readFully(@NotNull byte[] b, int off, int len) throws IOException { |
| ensure(len); |
| |
| buf.get(b, off, len); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public int skipBytes(int n) throws IOException { |
| if (buf.remaining() >= n) |
| buf.position(buf.position() + n); |
| else |
| seek(pos + n); |
| |
| return n; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public boolean readBoolean() throws IOException { |
| return readByte() == 1; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public byte readByte() throws IOException { |
| ensure(1); |
| |
| return buf.get(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public int readUnsignedByte() throws IOException { |
| return readByte() & 0xFF; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public short readShort() throws IOException { |
| ensure(2); |
| |
| return buf.getShort(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public int readUnsignedShort() throws IOException { |
| return readShort() & 0xFFFF; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public char readChar() throws IOException { |
| ensure(2); |
| |
| return buf.getChar(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public int readInt() throws IOException { |
| ensure(4); |
| |
| return buf.getInt(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public long readLong() throws IOException { |
| ensure(8); |
| |
| return buf.getLong(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public float readFloat() throws IOException { |
| ensure(4); |
| |
| return buf.getFloat(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public double readDouble() throws IOException { |
| ensure(8); |
| |
| return buf.getDouble(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public String readLine() throws IOException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override public String readUTF() throws IOException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * @param skipCheck If CRC check should be skipped. |
| * @return autoclosable fileInput, after its closing crc32 will be calculated and compared with saved one |
| */ |
| public Crc32CheckingFileInput startRead(boolean skipCheck) { |
| return new Crc32CheckingFileInput(this, skipCheck); |
| } |
| } |