mirror of
https://github.com/chrislusf/seaweedfs
synced 2024-05-19 01:40:15 +02:00
134 lines
3.6 KiB
Java
134 lines
3.6 KiB
Java
/*
|
|
* Copyright 2013 the original author or authors.
|
|
*
|
|
* Licensed 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 seaweedfs.client.btree.serialize;
|
|
|
|
import javax.annotation.Nullable;
|
|
import java.io.EOFException;
|
|
import java.io.IOException;
|
|
import java.io.InputStream;
|
|
|
|
public abstract class AbstractDecoder implements Decoder {
|
|
private DecoderStream stream;
|
|
|
|
@Override
|
|
public InputStream getInputStream() {
|
|
if (stream == null) {
|
|
stream = new DecoderStream();
|
|
}
|
|
return stream;
|
|
}
|
|
|
|
@Override
|
|
public void readBytes(byte[] buffer) throws IOException {
|
|
readBytes(buffer, 0, buffer.length);
|
|
}
|
|
|
|
@Override
|
|
public byte[] readBinary() throws EOFException, IOException {
|
|
int size = readSmallInt();
|
|
byte[] result = new byte[size];
|
|
readBytes(result);
|
|
return result;
|
|
}
|
|
|
|
@Override
|
|
public int readSmallInt() throws EOFException, IOException {
|
|
return readInt();
|
|
}
|
|
|
|
@Override
|
|
public long readSmallLong() throws EOFException, IOException {
|
|
return readLong();
|
|
}
|
|
|
|
@Nullable
|
|
@Override
|
|
public Integer readNullableSmallInt() throws IOException {
|
|
if (readBoolean()) {
|
|
return readSmallInt();
|
|
} else {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public String readNullableString() throws EOFException, IOException {
|
|
if (readBoolean()) {
|
|
return readString();
|
|
} else {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void skipBytes(long count) throws EOFException, IOException {
|
|
long remaining = count;
|
|
while (remaining > 0) {
|
|
long skipped = maybeSkip(remaining);
|
|
if (skipped <= 0) {
|
|
break;
|
|
}
|
|
remaining -= skipped;
|
|
}
|
|
if (remaining > 0) {
|
|
throw new EOFException();
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public <T> T decodeChunked(DecodeAction<Decoder, T> decodeAction) throws EOFException, Exception {
|
|
throw new UnsupportedOperationException();
|
|
}
|
|
|
|
@Override
|
|
public void skipChunked() throws EOFException, IOException {
|
|
throw new UnsupportedOperationException();
|
|
}
|
|
|
|
protected abstract int maybeReadBytes(byte[] buffer, int offset, int count) throws IOException;
|
|
|
|
protected abstract long maybeSkip(long count) throws IOException;
|
|
|
|
private class DecoderStream extends InputStream {
|
|
byte[] buffer = new byte[1];
|
|
|
|
@Override
|
|
public long skip(long n) throws IOException {
|
|
return maybeSkip(n);
|
|
}
|
|
|
|
@Override
|
|
public int read() throws IOException {
|
|
int read = maybeReadBytes(buffer, 0, 1);
|
|
if (read <= 0) {
|
|
return read;
|
|
}
|
|
return buffer[0] & 0xff;
|
|
}
|
|
|
|
@Override
|
|
public int read(byte[] buffer) throws IOException {
|
|
return maybeReadBytes(buffer, 0, buffer.length);
|
|
}
|
|
|
|
@Override
|
|
public int read(byte[] buffer, int offset, int count) throws IOException {
|
|
return maybeReadBytes(buffer, offset, count);
|
|
}
|
|
}
|
|
}
|