netty5/codec-smtp/src/main/java/io/netty/handler/codec/smtp/DefaultLastSmtpContent.java
Trustin Lee 3a9f472161 Make retained derived buffers recyclable
Related: #4333 #4421 #5128

Motivation:

slice(), duplicate() and readSlice() currently create a non-recyclable
derived buffer instance. Under heavy load, an application that creates a
lot of derived buffers can put the garbage collector under pressure.

Modifications:

- Add the following methods which creates a non-recyclable derived buffer
  - retainedSlice()
  - retainedDuplicate()
  - readRetainedSlice()
- Add the new recyclable derived buffer implementations, which has its
  own reference count value
- Add ByteBufHolder.retainedDuplicate()
- Add ByteBufHolder.replace(ByteBuf) so that..
  - a user can replace the content of the holder in a consistent way
  - copy/duplicate/retainedDuplicate() can delegate the holder
    construction to replace(ByteBuf)
- Use retainedDuplicate() and retainedSlice() wherever possible
- Miscellaneous:
  - Rename DuplicateByteBufTest to DuplicatedByteBufTest (missing 'D')
  - Make ReplayingDecoderByteBuf.reject() return an exception instead of
    throwing it so that its callers don't need to add dummy return
    statement

Result:

Derived buffers are now recycled when created via retainedSlice() and
retainedDuplicate() and derived from a pooled buffer
2016-05-17 11:16:13 +02:00

78 lines
2.0 KiB
Java

/*
* Copyright 2016 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.handler.codec.smtp;
import io.netty.buffer.ByteBuf;
import io.netty.util.internal.UnstableApi;
/**
* Default implementation of {@link LastSmtpContent} that does no validation of the raw data passed in.
*/
@UnstableApi
public final class DefaultLastSmtpContent extends DefaultSmtpContent implements LastSmtpContent {
/**
* Creates a new instance using the given data.
*/
public DefaultLastSmtpContent(ByteBuf data) {
super(data);
}
@Override
public LastSmtpContent copy() {
return (LastSmtpContent) super.copy();
}
@Override
public LastSmtpContent duplicate() {
return (LastSmtpContent) super.duplicate();
}
@Override
public LastSmtpContent retainedDuplicate() {
return (LastSmtpContent) super.retainedDuplicate();
}
@Override
public LastSmtpContent replace(ByteBuf content) {
return new DefaultLastSmtpContent(content);
}
@Override
public DefaultLastSmtpContent retain() {
super.retain();
return this;
}
@Override
public DefaultLastSmtpContent retain(int increment) {
super.retain(increment);
return this;
}
@Override
public DefaultLastSmtpContent touch() {
super.touch();
return this;
}
@Override
public DefaultLastSmtpContent touch(Object hint) {
super.touch(hint);
return this;
}
}