146 lines
4.0 KiB
Java
146 lines
4.0 KiB
Java
/*
|
|
* Copyright 2013 The Netty Project
|
|
*
|
|
* The Netty Project 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 io.netty.channel;
|
|
|
|
import io.netty.util.Recycler;
|
|
import io.netty.util.Recycler.Handle;
|
|
|
|
import java.util.Arrays;
|
|
|
|
/**
|
|
* A simple array-backed list that holds one or more messages.
|
|
*/
|
|
final class MessageList {
|
|
|
|
private static final int DEFAULT_INITIAL_CAPACITY = 8;
|
|
private static final int MIN_INITIAL_CAPACITY = 4;
|
|
|
|
private static final Recycler<MessageList> RECYCLER = new Recycler<MessageList>() {
|
|
@Override
|
|
protected MessageList newObject(Handle handle) {
|
|
return new MessageList(handle);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Create a new empty {@link MessageList} instance.
|
|
*/
|
|
static MessageList newInstance() {
|
|
MessageList ret = RECYCLER.get();
|
|
return ret;
|
|
}
|
|
|
|
private final Handle handle;
|
|
private Object[] messages;
|
|
private ChannelPromise[] promises;
|
|
private int size;
|
|
|
|
MessageList(Handle handle) {
|
|
this(handle, DEFAULT_INITIAL_CAPACITY);
|
|
}
|
|
|
|
MessageList(Handle handle, int initialCapacity) {
|
|
this.handle = handle;
|
|
initialCapacity = normalizeCapacity(initialCapacity);
|
|
messages = new Object[initialCapacity];
|
|
promises = new ChannelPromise[initialCapacity];
|
|
}
|
|
|
|
/**
|
|
* Return the current size of this {@link MessageList} and so how many messages it holds.
|
|
*/
|
|
int size() {
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* Return {@code true} if this {@link MessageList} is empty and so contains no messages.
|
|
*/
|
|
boolean isEmpty() {
|
|
return size == 0;
|
|
}
|
|
|
|
/**
|
|
* Add the message to this {@link MessageList} and return itself.
|
|
*/
|
|
MessageList add(Object message, ChannelPromise promise) {
|
|
int oldSize = size;
|
|
int newSize = oldSize + 1;
|
|
ensureCapacity(newSize);
|
|
messages[oldSize] = message;
|
|
promises[oldSize] = promise;
|
|
size = newSize;
|
|
return this;
|
|
}
|
|
|
|
/**
|
|
* Returns the backing array of this list.
|
|
*/
|
|
Object[] messages() {
|
|
return messages;
|
|
}
|
|
|
|
ChannelPromise[] promises() {
|
|
return promises;
|
|
}
|
|
|
|
/**
|
|
* Clear and recycle this instance.
|
|
*/
|
|
boolean recycle() {
|
|
Arrays.fill(messages, 0, size, null);
|
|
Arrays.fill(promises, 0, size, null);
|
|
size = 0;
|
|
return RECYCLER.recycle(this, handle);
|
|
}
|
|
|
|
private void ensureCapacity(int capacity) {
|
|
if (messages.length >= capacity) {
|
|
return;
|
|
}
|
|
|
|
final int size = this.size;
|
|
capacity = normalizeCapacity(capacity);
|
|
|
|
Object[] newMessages = new Object[capacity];
|
|
System.arraycopy(messages, 0, newMessages, 0, size);
|
|
messages = newMessages;
|
|
|
|
ChannelPromise[] newPromises = new ChannelPromise[capacity];
|
|
System.arraycopy(promises, 0, newPromises, 0, size);
|
|
promises = newPromises;
|
|
}
|
|
|
|
private static int normalizeCapacity(int initialCapacity) {
|
|
if (initialCapacity <= MIN_INITIAL_CAPACITY) {
|
|
initialCapacity = MIN_INITIAL_CAPACITY;
|
|
} else {
|
|
initialCapacity |= initialCapacity >>> 1;
|
|
initialCapacity |= initialCapacity >>> 2;
|
|
initialCapacity |= initialCapacity >>> 4;
|
|
initialCapacity |= initialCapacity >>> 8;
|
|
initialCapacity |= initialCapacity >>> 16;
|
|
initialCapacity ++;
|
|
|
|
if (initialCapacity < 0) {
|
|
initialCapacity >>>= 1;
|
|
}
|
|
}
|
|
return initialCapacity;
|
|
}
|
|
}
|