![]() As a result, the top-level function often ends up acting as a catch-all, making the errors much less meaningful because they are handled far from their source. The green arrow shows how an exception can jump several levels up the stack before being handled in a catch.Īs you can see, it can be difficult to remember if an exception has been handled previously without drawing a diagram (such as the one above) to keep track of everything. The blue arrow highlights that any remaining statements will be skipped once an exception is thrown. As an example, consider the diagram below. ![]() Rather than following the usual flow of data through parameters and return values, Java’s exceptions occur outside the normal function pattern, resulting in confusing and fragile code. If exceptions are a common or even essential part of your application, it becomes increasingly difficult to understand the codebase as it grows larger and more complex. In addition, only a small portion of Java’s exceptions are checked, so many exceptions are still very easy to miss. While checked exceptions are somewhat guarded by the compiler, it’s still too easy to add a throws clause or wrap the exception in a try/catch block without paying any attention to the error case and neglecting to handle the exception properly. Java introduced checked exceptions in an attempt to solve this problem by enforcing either annotating the function that might throw that exception or catching the exception immediately. ![]() While ignoring error cases can be useful for putting together a quick prototype, it can be difficult to track down all the places where an exception can be thrown when you attempt to ready an application for production. If the program completely fails to catch an exception, the program will crash. Java’s exceptions allow the caller of a function to ignore any errors the function might produce. We’ll cover four ways dealing with Java’s exceptions can be difficult and then wrap up with a few ways modern languages like Scala can help programmers make sure they correctly handle errors. Unfortunately, since dealing with exceptions can be messy and complicated, error handling often comes into play as an almost-forgotten last step for polishing an application. Users expect software to gracefully handle errors, either in the background or with a user-friendly and actionable description of the issue. An application shouldn’t crash just because a user enters invalid data or a web service returns a 500. That said, you may find parts of this paper enlightening, especially with regards to Scala performance.Error handling is important for many common operations-from dealing with user input to making network requests. Suffice it to say, benchmarks never tell the full story, and there are many factors to consider when choosing a programming language. The phrase “lies, damn lies and benchmarks” is by now a cliche. Go offers concise notion and very fast compile time, but is still immature.The algorithm was simplest to implement in Java, but garbage collection settings make both Java and Scala difficult to benchmark accurately.Scala provides the most concise notation and optimization of code complexity.C++ provides the best performance by far, but it requires the most extensive language-specific tuning.However, the paper notes: “While the benchmark itself is simple and compact, it employs many language features, in particular, higher-level data structures (lists, maps, lists and arrays of sets and lists), a few algorithms (union/find, dfs/deep recursion, and loop recognition based on Tarjan), iterations over collection types, some object oriented features, and interesting memory allocation patterns.”Ībove: Run-time measurements, including a few optimizations.Īfter benchmark tests were published within Google various employees took a stab at optimizing the code for specific languages. An algorithm was implemented using each language’s “idiomatic container classes, looping constructs, and memory/object allocation schemes.” A team at Google created a “simple and compact” benchmark that didn’t take advantage of language-specific features. Google has published a paper (PDF) comparing performance of four programming languages, C++, its own language Go, Java and Scala.
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