如何创建表示Java的字符串，就像它是无符号的64位值一样

My component is handed a long value that I later use as a key into a cache. The key itself is a string representation of the long value as if it were unsigned 64-bit value. That is, when my component is handed -2944827264075010823L, I need to convert that into the string key "15501916809634540793".My component is handed a long value that I late