Files
state-management/src/main/java/com/serliunx/statemanagement/machine/DefaultConcurrentStateMachine.java

133 lines
3.6 KiB
Java

package com.serliunx.statemanagement.machine;
import com.serliunx.statemanagement.machine.handler.StateHandlerWrapper;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Consumer;
/**
* @author <a href="mailto:serliunx@yeah.net">SerLiunx</a>
* @version 1.0.0
* @since 2025/2/6
*/
public class DefaultConcurrentStateMachine<S> extends AbstractStateMachine<S> implements ConcurrentStateMachine<S> {
/**
* 当前状态
*/
private final AtomicInteger index = new AtomicInteger(0);
DefaultConcurrentStateMachine(List<S> stateList,
Map<S, List<StateHandlerWrapper<S>>> entryHandlers,
Map<S, List<StateHandlerWrapper<S>>> leaveHandlers,
Map<String, List<StateHandlerWrapper<S>>> exchangeHandlers,
Map<Object, List<Consumer<StateMachine<S>>>> eventRegistries,
Executor executor,
Boolean async) {
super(stateList, entryHandlers, leaveHandlers, exchangeHandlers, eventRegistries, executor, async);
}
@Override
public boolean compareAndSet(S expectedValue, S newValue) {
int current = indexOf(expectedValue);
int newIndex = indexOf(newValue);
if (current == -1 || newIndex == -1)
return false;
return index.compareAndSet(current, newIndex);
}
/**
* 使用CAS不断尝试将当前状态重置回默认值(0)
*
* @param invokeHandlers 是否唤醒状态处理器
*/
@Override
public void reset(boolean invokeHandlers) {
if (isDefault())
return;
exchangeToTarget(0);
// TODO invokeHandlers
}
@Override
public boolean switchTo(S state, boolean invokeHandlers) {
int i = indexOf(state);
if (i == -1 ||
i == index.get()) {
return false;
}
exchangeToTarget(i);
return true;
}
@Override
public S switchPrevAndGet(boolean invokeHandlers) {
S oldState = get(index.get());
S newState = get(index.get());
if (invokeHandlers)
invokeHandlers(oldState, newState);
return newState;
}
@Override
public S getAndSwitchPrev(boolean invokeHandlers) {
return super.getAndSwitchPrev(invokeHandlers);
}
@Override
public void switchPrev(boolean invokeHandlers) {
super.switchPrev(invokeHandlers);
}
@Override
public S switchNextAndGet(boolean invokeHandlers) {
return super.switchNextAndGet(invokeHandlers);
}
@Override
public S getAndSwitchNext(boolean invokeHandlers) {
return super.getAndSwitchNext(invokeHandlers);
}
@Override
public void switchNext(boolean invokeHandlers) {
super.switchNext(invokeHandlers);
}
@Override
public void publish(Object event) {
}
/**
* 是否为默认状态
*/
private boolean isDefault() {
return index.get() == 0;
}
/**
* 移动下标至上一个状态
*/
public void exchangeToPrev() {
final int size = size();
}
/**
* 切换到指定状态值
* <li> 使用CAS一直尝试, 直到成功
*
* @param target 目标值
*/
private void exchangeToTarget(int target) {
int currentValue;
do {
currentValue = index.get();
} while (!index.compareAndSet(currentValue, target));
}
}