io.micronaut.http.netty.PublisherAsStream Maven / Gradle / Ivy
/*
* Copyright 2017-2023 original 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
*
* https://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 io.micronaut.http.netty;
import io.micronaut.core.annotation.Internal;
import io.micronaut.core.annotation.NonNull;
import io.netty.buffer.ByteBuf;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
/**
* Transform a {@link PublisherAsBlocking} of buffers into a {@link InputStream}.
*
* @author Jonas Konrad
* @since 4.2.0
*/
@Internal
public final class PublisherAsStream extends InputStream {
private final PublisherAsBlocking publisherAsBlocking;
private ByteBuf buffer;
public PublisherAsStream(PublisherAsBlocking publisherAsBlocking) {
this.publisherAsBlocking = publisherAsBlocking;
}
@Override
public int read() throws IOException {
byte[] arr = new byte[1];
int n = read(arr);
return n == -1 ? -1 : arr[0] & 0xff;
}
@Override
public int read(@NonNull byte[] b, int off, int len) throws IOException {
while (buffer == null) {
try {
ByteBuf o = publisherAsBlocking.take();
if (o == null) {
Throwable failure = publisherAsBlocking.getFailure();
if (failure == null) {
return -1;
} else {
throw new IOException(failure);
}
}
if (o.readableBytes() == 0) {
o.release();
continue;
}
buffer = o;
} catch (InterruptedException e) {
throw new InterruptedIOException();
}
}
int toRead = Math.min(len, buffer.readableBytes());
buffer.readBytes(b, off, toRead);
if (buffer.readableBytes() == 0) {
buffer.release();
buffer = null;
}
return toRead;
}
@Override
public void close() throws IOException {
if (buffer != null) {
buffer.release();
buffer = null;
}
publisherAsBlocking.close();
}
}