小编qui*_*tin的帖子

我们应该使用哪些用例ArrayIndexOutOfBoundsException和`IndexOutOfBoundsException？

public class S3ButcketTest
{

public static void main(String args[])
{
    System.setSecurityManager(new RMISecurityManager());
    ForkJoinPool pool = new ForkJoinPool(1);
    System.out.println("main: "+Policy.getPolicy());

    pool.execute(new Runnable()
    {
        @Override
        public void run()
        {
            try
            {
                Thread.sleep(1000);
            }
            catch (InterruptedException e)
            {
                e.printStackTrace();
            }
            System.out.println("pool: "+Policy.getPolicy());
        }
    });

    pool.shutdown();
    try
    {
        pool.awaitTermination(1000, TimeUnit.SECONDS);
    }
    catch (InterruptedException e)
    {
        e.printStackTrace();
    }
}
}

使用 VM 参数在两个不同的 JDK 版本（8 和 11）上运行：-Djava.security.policy=C:\test_system.policy

test_system.policy 内容：

grant {
permission java.security.AllPermission;
};

使用JDK11运行时的输出：

main: sun.security.provider.PolicyFile@4cb2c100
Exception in thread "ForkJoinPool-1-worker-3" java.security.AccessControlException: access denied ("java.security.SecurityPermission" …

我使用 spring Reactor 库编写了一个逻辑，以异步模式获取所有操作员，然后获取每个操作员的所有设备（分页）。

创建一个 Flux 来获取所有运算符，然后订阅它。

    final Flux<List<OperatorDetails>> operatorDetailsFlux = reactiveResourceProvider.getOperators();
    operatorDetailsFlux
        .subscribe(operatorDetailsList -> {
          for (final OperatorDetails operatorDetails : operatorDetailsList) {
            getAndCacheDevicesForOperator(operatorDetails.getId());
          }
        });

现在，对于每个运营商，我正在获取需要多个订阅才能获取设备 mono 的设备，该设备通过订阅 MONO 来异步获取所有页面。

private void getAndCacheDevicesForOperator(final int operatorId) {
    Mono<DeviceListResponseEntity> deviceListResponseEntityMono = reactiveResourceProvider.getConnectedDeviceMonoWithRetryAndErrorSpec(
        operatorId, 0);

    deviceListResponseEntityMono.subscribe(deviceListResponseEntity -> {
      final PaginatedResponseEntity PaginatedResponseEntity = deviceListResponseEntity.getData();
      final long totalDevicesInOperator = PaginatedResponseEntity.getTotalCount();


      int deviceCount = PaginatedResponseEntity.getCount();
      while (deviceCount < totalDevicesInOperator) {
        final Mono<DeviceListResponseEntity> deviceListResponseEntityPageMono = reactiveResourceProvider.getConnectedDeviceMonoWithRetryAndErrorSpec(
            operatorId, deviceCount);

        deviceListResponseEntityPageMono.subscribe(deviceListResponseEntityPage -> {
          final List<DeviceDetails> deviceDetailsList = deviceListResponseEntityPage.getData() …

就像我有这两个场景我们必须处理FileNotFoundException

情况1:

    try {
        FileInputStream fis = new FileInputStream("test1.txt");
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } 

案例2:

    try {
        FileInputStream fis = new FileInputStream("test1.txt");
    } catch (Exception e) {
        e.printStackTrace();
    }

在两种情况下,打印的Stack Trace都是相同的.我想知道两种实现之间的区别以及应该首选的内容？

我有一个正则表达式/ \ s *，\ s * /，它匹配左空格，然后是逗号，然后是右空格。

例：

var str = "john,walker    james  , paul";
var arr = str.split(/\s*,\s*/);
Values in arr = [john,walker james,paul] // Size: 3

带有汉字的示例：

var str = "?????   ?? ???";
var arr = str.split(/\s*,\s*/);
Values in arr = ["?????   ?? ???"] // Size: 1, All values at index 0 no splitting happened

尝试使用Unicode分割字符：

var str = "john,walker    james  , paul";
var arr = str.split(/\u0020*\u002C\u0020*/);
Values in arr = [john,walker james,paul] // Size: 3 …