HarmonyOS java代码long和byte[]互相转换如何实现

参考如下写法：

let data = BigInt("9223372036854775807")
let tempBE = buffer.alloc(8)
tempBE.fill(0)
tempBE.writeBigInt64BE(data)
let intArrBE = new Int8Array(tempBE.buffer);
console.debug('intArrBE:' + intArrBE.toString())
let buf = buffer.from(intArrBE.buffer);
console.log('BigInt:'+buf.readBigInt64BE().toString());