java - Null Pointer - Timer + Array of objects

Question

I have discovered were the error was, was declaring the array as laneCar[] in one part of my code and laneCars[] elsewhere which was causing null pointer errors.

Answer 1

您正在初始化人口循环中的数组，例如

for (int r = 0; r < 13; r++)
{ 
    roadLane[] lanes = new roadLane[13];
    // ...

因此，每次通过循环时，您都会创建一个新数组，然后在其中填充一个元素。所有其他元素将为空。

您可能需要先执行此操作，例如

roadLane[] lanes = new roadLane[13];
for (int r = 0; r < 13; r++)
{ 
    // ...