你真的會正確使用日誌嗎？

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WARN [93ef3E0120160803114444-1.2] [main] [ClassPathXmlApplicationContext] Exception encountered during context initialization - cancelling refresh attempt","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"日誌時間","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"作爲日誌產生的日期和時間，這個數據非常重要，一般精確到毫秒。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"由於一般按天滾動日誌文件，日期不需要放在這個時間中，使用 HH:mm:ss.SSS格式即可。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"日誌級別","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"日誌級別主要使用 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級別日誌原則是在生產環境中，通過 INFO 和更高級別的日誌，可以瞭解系統的運行狀況，以及出現問題或者異常時，能快速地對問題進行定位，還原當時調用的上下文數據，能重現問題。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"建議在項目完成後，在測試環境將日誌級別調成 INFO，然後通過 INFO 級別的信息看看是否能瞭解這個應用的運用情況，如果出現問題後是否這些日誌能否提供有用的排查問題的信息。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"WARN","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"WARN 級別的主要輸出警告性質的內容，這些內容是可以預知且是有規劃的，比如，某個方法入參爲空或者該參數的值不滿足運行該方法的條件時。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在 WARN 級別的時應輸出較爲詳盡的信息，以便於事後對日誌進行分析，不要直接寫成：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"不好的日誌：","attrs":{}}]},{"type":"codeblock","attrs":{"lang":null},"content":[{"type":"text","text":"log.warn( \"name is null\");","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"除了輸出警告的原因之外，還需要將其他參數內容都輸出，以便於有更多的信息供爲日誌分析的參考。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"推薦的日誌：","attrs":{}}]},{"type":"codeblock","attrs":{"lang":null},"content":[{"type":"text","text":"log.warn( \"[{}] name is null, ignore the method, arg0: {}, arg1: {}\", methodName , arg0 , arg1 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