Handle exception for unhex & refine doc #62

Job	Run time
Linux (JDK 11), Avatica main	20m 10s
CheckerFramework (JDK 11), oldest Guava	12m 39s
CheckerFramework (JDK 11)	19m 16s
Error Prone (JDK 11), latest Guava	6m 51s
Druid Tests	9m 0s
Linux (JDK 11), Pacific/Chatham Timezone	15m 4s
Linux (JDK 17)	13m 48s
Linux (JDK 19)	15m 17s
Linux (JDK 8), latest Guava, America/New_York Timezone	14m 20s
Linux (JDK 8), oldest Guava, America/New_York Timezone	15m 21s
Linux (JDK 8) Slow Tests	0s
macOS (JDK 19)	13m 4s
Windows (JDK 8)	20m 27s
Windows (JDK 17)	18m 8s
	3h 13m 25s

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