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/*
* Copyright (c) 2017 - 2019, SmartDeviceLink Consortium, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the
* distribution.
*
* Neither the name of the SmartDeviceLink Consortium, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package com.smartdevicelink.managers;
import android.support.annotation.IntDef;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
public class StreamingStateMachine {
@IntDef({NONE, READY, STARTED, STOPPED, ERROR})
@Retention(RetentionPolicy.SOURCE)
public @interface StreamingState {}
public static final int NONE = 0x00, READY = 0x30, STARTED = 0x60, STOPPED = 0x90, ERROR = 0xC0;
private @StreamingState int state = NONE;
private final Object STATE_LOCK = new Object();
public StreamingStateMachine(){}
public void transitionToState(int state) {
if(state != NONE && state != READY && state != STARTED
&& state != STOPPED && state != ERROR) {
return;
}
synchronized (STATE_LOCK) {
if(isValidTransition(this.state, state)){
this.state = state;
}
}
}
public @StreamingState int getState() {
synchronized (STATE_LOCK) {
return state;
}
}
private boolean isValidTransition(int prev_state, int next_state){
if(prev_state == next_state){
return false;
}
switch (prev_state){
case NONE:
if((next_state == READY) || (next_state == ERROR)){
return true;
}
break;
case READY:
if((next_state == STARTED) || (next_state == ERROR)){
return true;
}
break;
case STARTED:
if((next_state == STOPPED) || (next_state == ERROR)){
return true;
}
break;
case STOPPED:
if((next_state == STARTED) || (next_state == NONE)){
return true;
}
break;
case ERROR:
if(next_state == NONE){
return true;
}
break;
default:
break;
}
return false;
}
}
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