netty5/codec/src/main/java/io/netty/handler/codec/ProtocolDetectionResult.java

81 lines
2.7 KiB
Java

/*
* Copyright 2015 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;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
/**
* Result of detecting a protocol.
*
* @param <T> the type of the protocol
*/
public final class ProtocolDetectionResult<T> {
@SuppressWarnings({ "rawtypes", "unchecked" })
private static final ProtocolDetectionResult NEEDS_MORE_DATE =
new ProtocolDetectionResult(ProtocolDetectionState.NEEDS_MORE_DATA, null);
@SuppressWarnings({ "rawtypes", "unchecked" })
private static final ProtocolDetectionResult INVALID =
new ProtocolDetectionResult(ProtocolDetectionState.INVALID, null);
private final ProtocolDetectionState state;
private final T result;
/**
* Returns a {@link ProtocolDetectionResult} that signals that more data is needed to detect the protocol.
*/
@SuppressWarnings("unchecked")
public static <T> ProtocolDetectionResult<T> needsMoreData() {
return NEEDS_MORE_DATE;
}
/**
* Returns a {@link ProtocolDetectionResult} that signals the data was invalid for the protocol.
*/
@SuppressWarnings("unchecked")
public static <T> ProtocolDetectionResult<T> invalid() {
return INVALID;
}
/**
* Returns a {@link ProtocolDetectionResult} which holds the detected protocol.
*/
@SuppressWarnings("unchecked")
public static <T> ProtocolDetectionResult<T> detected(T protocol) {
return new ProtocolDetectionResult<T>(ProtocolDetectionState.DETECTED, checkNotNull(protocol, "protocol"));
}
private ProtocolDetectionResult(ProtocolDetectionState state, T result) {
this.state = state;
this.result = result;
}
/**
* Return the {@link ProtocolDetectionState}. If the state is {@link ProtocolDetectionState#DETECTED} you
* can retrieve the protocol via {@link #detectedProtocol()}.
*/
public ProtocolDetectionState state() {
return state;
}
/**
* Returns the protocol if {@link #state()} returns {@link ProtocolDetectionState#DETECTED}, otherwise {@code null}.
*/
public T detectedProtocol() {
return result;
}
}