java - 如何在 Java 中处理仿函数对象内的已检查异常

Question

我们使用 http://jedi.codehaus.org用于处理集合并以功能方式操作它们的库。我们最近在执行类似以下操作时遇到了一个问题:

public class Address {
    //constructors and stuff

    public KiloWatts electricityConsumed(Duration timePeriod) throw NoElectricitySupply {
        .... does stuff but can throw checked exception
    } 
}

假设我们有一个地址集合，并且我们想对与每个地址关联的 UnitsOfElectricity 执行某些操作，您将如何处理抛出的异常，例如:

public KiloWatts totalEnergyConsumed(Address... addresses, final Duration timePeriod) {
     List<KiloWatts> energyConsumedPerAddress = FunctionalPrimitives.collect(addresses, new Functor<Address, KiloWatts>{
         public KiloWatts execute(Address address){
              try {
                  return address.energyConsumed(timePeriod);
              } catch (NoElectricitySupply e) {

                  //What do you do here?

              }
         }
     });
}

你会如何处理异常？

Answer 1

据我所知，您有 2 个选择:

1. 抛出运行时异常(并忽略它)；或
2. 抛出运行时异常，使用它来“编码”经过接口(interface)边界的已检查异常。

对于 (2)，类似于:

public KiloWatts totalEnergyConsumed(Address... addresses, final Duration timePeriod) {
    try {
        List<KiloWatts> energyConsumedPerAddress = FunctionalPrimitives.collect(addresses, new Functor<Address, KiloWatts>{
            public KiloWatts execute(Address address){
                try {
                    return address.energyConsumed(timePeriod);
                } catch (NoElectricitySupply e) {
                    throw new RuntimeException("internal marshalling exception", e);
                }
           }
       });
    } catch(RuntimeException re) {
        throw e.getCause();
    }
}