chinabugotech/hutool · error · IllegalStateException

Can't stop StopWatch: it's not running

Error message

Can't stop StopWatch: it's not running

What it means

Error "Can't stop StopWatch: it's not running" thrown in chinabugotech/hutool.

Source

Thrown at hutool-core/src/main/java/cn/hutool/core/date/StopWatch.java:170

	 * @param taskName 新开始的任务名称
	 * @throws IllegalStateException 前一个任务没有结束
	 */
	public void start(String taskName) throws IllegalStateException {
		if (null != this.currentTaskName) {
			throw new IllegalStateException("Can't start StopWatch: it's already running");
		}
		this.currentTaskName = taskName;
		this.startTimeNanos = System.nanoTime();
	}

	/**
	 * 停止当前任务
	 *
	 * @throws IllegalStateException 任务没有开始
	 */
	public void stop() throws IllegalStateException {
		if (null == this.currentTaskName) {
			throw new IllegalStateException("Can't stop StopWatch: it's not running");
		}

		final long lastTime = System.nanoTime() - this.startTimeNanos;
		final long safeLastTime = Math.max(0, lastTime);
		this.totalTimeNanos += safeLastTime;
		this.lastTaskInfo = new TaskInfo(this.currentTaskName, safeLastTime);
		if (null != this.taskList) {
			this.taskList.add(this.lastTaskInfo);
		}
		++this.taskCount;
		this.currentTaskName = null;
	}

	/**
	 * 检查是否有正在运行的任务
	 *
	 * @return 是否有正在运行的任务
	 * @see #currentTaskName()

View on GitHub (pinned to 8870454b2a)

Solutions

1. Call start() before stop(); ensure the StopWatch is running.
2. Guard with isRunning() before calling stop().

When it happens

Trigger: Thrown at hutool-core/src/main/java/cn/hutool/core/date/StopWatch.java:170 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of chinabugotech/hutool@8870454b2a (2026-08-14). Data as JSON: /api/errors/ee60d095ae0c48ee. Report an issue: GitHub.