import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Expands the event queue capacity, or truncates if capacity is lower than
 * current capacity. Then only the newest entries are kept
 * @param self self reference
 * @param newCapacity new capacity
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static void expandEventQueueCapacity(final Object self, final Object newCapacity) {
    final LinkedList<RuntimeEvent<?>> q = getEventQueue(self);
    final int nc = JSType.toInt32(newCapacity);
    while (q.size() > nc) {
        q.removeFirst();
    }
    setEventQueueCapacity(self, nc);
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Add a runtime event to the runtime event queue. The queue has a fixed
 * size {@link RuntimeEvent#RUNTIME_EVENT_QUEUE_SIZE} and the oldest
 * entry will be thrown out of the queue is about to overflow
 * @param self self reference
 * @param event event to add
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static void addRuntimeEvent(final Object self, final Object event) {
    final LinkedList<RuntimeEvent<?>> q = getEventQueue(self);
    final int cap = (Integer)getEventQueueCapacity(self);
    while (q.size() >= cap) {
        q.removeFirst();
    }
    q.addLast(getEvent(event));
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Get the capacity of the event queue
 * @param self self reference
 * @return capacity of event queue as an integer
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static Object getEventQueueCapacity(final Object self) {
    final ScriptObject sobj = (ScriptObject)self;
    Integer cap;
    if (sobj.has(EVENT_QUEUE_CAPACITY)) {
        cap = JSType.toInt32(sobj.get(EVENT_QUEUE_CAPACITY));
    } else {
        setEventQueueCapacity(self, cap = RuntimeEvent.RUNTIME_EVENT_QUEUE_SIZE);
    }
    return cap;
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Remove a specific runtime event from the event queue
 * @param self self reference
 * @param event event to remove
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static void removeRuntimeEvent(final Object self, final Object event) {
    final LinkedList<RuntimeEvent<?>> q  = getEventQueue(self);
    final RuntimeEvent<?>             re = getEvent(event);
    if (!q.remove(re)) {
        throw new IllegalStateException("runtime event " + re + " was not in event queue");
    }
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
@SuppressWarnings("unchecked")
private static LinkedList<RuntimeEvent<?>> getEventQueue(final Object self) {
    final ScriptObject sobj = (ScriptObject)self;
    LinkedList<RuntimeEvent<?>> q;
    if (sobj.has(EVENT_QUEUE)) {
        q = (LinkedList<RuntimeEvent<?>>)((ScriptObject)self).get(EVENT_QUEUE);
    } else {
        ((ScriptObject)self).set(EVENT_QUEUE, q = new LinkedList<>(), NashornCallSiteDescriptor.CALLSITE_STRICT);
    }
    return q;
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
private static void logEvent(final RuntimeEvent<?> event) {
    if (event != null) {
        final Global global = Context.getGlobal();
        if (global.has("Debug")) {
            final ScriptObject debug = (ScriptObject)global.get("Debug");
            final ScriptFunction addRuntimeEvent = (ScriptFunction)debug.get("addRuntimeEvent");
            ScriptRuntime.apply(addRuntimeEvent, debug, event);
        }
    }
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Clear the runtime event queue
 * @param self self reference
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static void clearRuntimeEvents(final Object self) {
    final LinkedList<RuntimeEvent<?>> q = getEventQueue(self);
    q.clear();
}
 

import jdk.nashorn.internal.runtime.events.RuntimeEvent; //导入依赖的package包/类
/**
 * Return the last runtime event in the queue
 * @param self self reference
 * @return the freshest event, null if queue is empty
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static Object getLastRuntimeEvent(final Object self) {
    final LinkedList<RuntimeEvent<?>> q = getEventQueue(self);
    return q.isEmpty() ? null : q.getLast();
}