仿效屈原投河自盡以明心志

Hi
I realise this is a complicated sentence. I think it means:

"imitate屈原by throwing themselves into a rice.

I want to ask, is投河自盡 a common phrase to mean lead one's self into trouble?

Thank you
仲記得19年前嘅今日，香港落咗場好大好大嘅雨。
今日，雖然天朗氣清，但大家心中都流住眼淚，因為親愛嘅流局長仿效屈原投河自盡，以明心志