com.swirlds.common.test.merkle.dummy.BlockingInputStream Maven / Gradle / Ivy
/*
* Copyright (C) 2018-2023 Hedera Hashgraph, LLC
*
* 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 com.swirlds.common.test.merkle.dummy;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* An input stream that can be caused to block.
*/
public class BlockingInputStream extends InputStream {
private final AtomicBoolean locked;
private final InputStream in;
/**
* Create a new blocking stream by wrapping another stream.
*
* @param in
* the stream to wrap
*/
public BlockingInputStream(final InputStream in) {
locked = new AtomicBoolean(false);
this.in = in;
}
/**
* Lock the stream, causing read calls to block.
*/
public void lock() {
locked.set(true);
}
/**
* Unlock the stream. Read calls will not block.
*/
public void unlock() {
locked.set(false);
}
/**
* {@inheritDoc}
*/
@Override
public int read() throws IOException {
while (locked.get()) {
Thread.onSpinWait();
}
return in.read();
}
}