spring FileDescriptor 源码
springboot FileDescriptor 代码
文件路径：/spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/socket/FileDescriptor.java
/*
* Copyright 2012-2021 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
*
* 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 org.springframework.boot.buildpack.platform.socket;
import java.io.Closeable;
import java.io.IOException;
import java.util.function.IntConsumer;
/**
* Provides access to the underlying file system representation of an open file.
*
* @author Phillip Webb
* @see #acquire()
*/
class FileDescriptor {
private final Handle openHandle;
private final Handle closedHandler;
private final IntConsumer closer;
private Status status = Status.OPEN;
private int referenceCount;
FileDescriptor(int handle, IntConsumer closer) {
this.openHandle = new Handle(handle);
this.closedHandler = new Handle(-1);
this.closer = closer;
}
/**
* Acquire an instance of the actual {@link Handle}. The caller must
* {@link Handle#close() close} the resulting handle when done.
* @return the handle
*/
synchronized Handle acquire() {
this.referenceCount++;
return (this.status != Status.OPEN) ? this.closedHandler : this.openHandle;
}
private synchronized void release() {
this.referenceCount--;
if (this.referenceCount == 0 && this.status == Status.CLOSE_PENDING) {
this.closer.accept(this.openHandle.value);
this.status = Status.CLOSED;
}
}
/**
* Close the underlying file when all handles have been released.
*/
synchronized void close() {
if (this.status == Status.OPEN) {
if (this.referenceCount == 0) {
this.closer.accept(this.openHandle.value);
this.status = Status.CLOSED;
}
else {
this.status = Status.CLOSE_PENDING;
}
}
}
/**
* The status of the file descriptor.
*/
private enum Status {
OPEN, CLOSE_PENDING, CLOSED
}
/**
* Provides access to the actual file descriptor handle.
*/
final class Handle implements Closeable {
private final int value;
private Handle(int value) {
this.value = value;
}
boolean isClosed() {
return this.value == -1;
}
int intValue() {
return this.value;
}
@Override
public void close() throws IOException {
if (!isClosed()) {
release();
}
}
}
}
相关信息
相关文章
0
赞
- 所属分类： 后端技术
- 本文标签： Spring Boot Java Spring
热门推荐
-
2、 - 优质文章
-
3、 gate.io
-
8、 golang
-
9、 openharmony
-
10、 Vue中input框自动聚焦