并行排除任务代码
class SuperTask {
constructor(parallelCount = 2) {
this.parallelCount = parallelCount;
this.tasks = [];
this.runningCount = 0;
}
add(task) {
return new Promise((resolve, reject) => {
this.tasks.push({ task, resolve, reject })
this._runTask()
})
};
_runTask() {
while (this.runningCount < this.parallelCount && this.tasks.length) {
const { task, resolve, reject } = this.tasks.pop();
this.runningCount++;
Promise.resolve(task()).then(resolve, reject).finally(() => {
this.runningCount--;
this._runTask()
})
}
}
}
function timeout(time) {
return new Promise(resolve => {
setTimeout(() => {
resolve()
}, time);
})
}
const superTask = new SuperTask()
function addTask(time, name) {
superTask.add(() => timeout(time)).then(() => console.log(`task ${name} finish`))
}
// addTask(10000, 1)
// addTask(2000, 2)
// addTask(3000, 3)
// addTask(4000, 4)
