java 编程思想中的PriorityBlockingQueue 部分里对PrioritizedTask的排序没有显式调用collection的sort方法。而是通过take时做的这个动作


java 编程思想中的PriorityBlockingQueue 在take是会调用comparable 的compareTo进行排序，故不需要显式调用collection的sort方法

这个方法是PriorityBlockingQueue的：

public E take() throws InterruptedException {

ReentrantLock localReentrantLock = this.lock;

localReentrantLock.lockInterruptibly();

try {

try {

while (this.q.size() == 0)

this.notEmpty.await();

} catch (InterruptedException localInterruptedException) {

this.notEmpty.signal();

throw localInterruptedException;

}

Object localObject1 = this.q.poll();//调用了poll方法并对poll进行了判空，这个poll是PriorityQueue的poll

assert (localObject1 != null);

return localObject1;

} finally {

localReentrantLock.unlock();

}

}

PriorityQueue的poll方法：

public E poll() {

if (this.size == 0)

return null;

int i = --this.size;

this.modCount += 1;

Object localObject1 = this.queue[0];

Object localObject2 = this.queue[i];

this.queue[i] = null;

if (i != 0)

siftDown(0, localObject2);//调用了内部的siftDown进行排序

return localObject1;

}

private void siftDown(int paramInt, E paramE)

{

if (this.comparator != null)

siftDownUsingComparator(paramInt, paramE);

else

siftDownComparable(paramInt, paramE);//java编程思想用的是comparable.

}

private void siftDownComparable(int paramInt, E paramE) {

Comparable localComparable = (Comparable)paramE;

int i = this.size >>> 1;

while (paramInt < i) {

int j = (paramInt << 1) + 1;

Object localObject = this.queue[j];

int k = j + 1;

if ((k < this.size) && (((Comparable)localObject).compareTo(this.queue[k]) > 0))

{

localObject = this.queue[(j = k)];

}if (localComparable.compareTo(localObject) <= 0)//调用了添加到PriorityBlockingQueue的元素的compareTo方法，java编程思想是重写了comparable的compareTo

break;

this.queue[paramInt] = localObject;

paramInt = j;

}

this.queue[paramInt] = localComparable;

}

java 编程思想的PrioritizedTask继承并重写了compareTo，详情请参考java编程思想4版728页。所以在本书中得到例子并没有调用Collections.sort(list).

至此我个人的疑惑