Someone on IRC was asking whether it was possible to do catch multiple types of exceptions at the same time in c#.<\/p>\n
In Java 7 there’s a feature from project coin<\/a> called multi catch that enables the following syntax:<\/p>\n Here the catch block catches either an ExceptionA or an ExceptionB. This can be useful if you want to handle several exceptions in the same way.<\/p>\n I don’t believe c# has a similar language feature, however since it has lambdas you can replicate something similar yourself like so:<\/p>\n We create a method called Try and pass it an Action. We then chain a call to a Catch method which we pass the Exceptions we want to catch as Type arguments. As you can see we can vary the number of type arguments. This is something you can’t do in Java partly due to type erasure.<\/p>\n The Try method simply passes the action through to a Catcher<\/p>\n and the Catch method has overloads for any number of exceptions you want to support. We can restrict the type arguments to only Exception types by using the where clause.<\/p>\n Here’s the full code listing:<\/p>\n This is why Java needs lambdas. Because they fix everything \u00ac_\u00ac<\/p>\n For reference, the closest I could do in Java prior to 7 was something like this:<\/p>\n I had to use an abstract class instead of lambdas as Java has no lambdas. I also had to create a new class for each number of type arguments I wanted because you can’t overload with variable numbers of type arguments.<\/p>\n I also had to use Gafter’s gadget<\/a> to access the types of the Exceptions to catch.<\/p>\n Here’s the full code listing. <\/p>\n Someone on IRC was asking whether it was possible to do catch multiple types of exceptions at the same time in c#. In Java 7 there’s a feature from project coin called multi catch that enables the following syntax: public class MultiCatch { public static void main(String… args) { try { throw new ExceptionA(); }… Read more »<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[25,8],"tags":[12,23],"yoast_head":"\n\n\n\n\n\n\n\n\n\n\n\n\r\npublic class MultiCatch {\r\n\tpublic static void main(String... args) {\r\n\t\ttry {\r\n\t\t\tthrow new ExceptionA();\t\r\n\t\t} catch (final ExceptionA | ExceptionB ex) {\r\n\t\t\tSystem.out.println(\"Got \" + ex.getClass().getSimpleName());\r\n\t\t}\r\n\t}\r\n}\r\n\r\nclass ExceptionA extends RuntimeException {}\r\nclass ExceptionB extends RuntimeException {}\r\n<\/pre>\n\r\nusing System;\r\n\r\npublic class MultiCatch {\r\n public static void Main() {\r\n Trier.Try(() => {\r\n throw new ExceptionA(\" Hello A\");\r\n }).Catch\r\n public static Catcher Try(Action action) {\r\n return new Catcher(action);\r\n }\r\n<\/pre>\n\r\n public void Catch
\r\nusing System;\r\n\r\npublic class MultiCatch {\r\n public static void Main() {\r\n Trier.Try(() => {\r\n throw new ExceptionA(\" Hello A\");\r\n }).Catch\r\npublic class MultiCatchWithoutCoin {\r\n\tpublic static void main(String... args) {\r\n\t\tnew TrierII\r\nimport java.lang.reflect.InvocationTargetException;\r\nimport java.lang.reflect.ParameterizedType;\r\nimport java.lang.reflect.Type;\r\nimport java.util.ArrayList;\r\n\r\npublic class MultiCatchWithoutCoin {\r\n\tpublic static void main(String... args) {\r\n\t\tnew TrierII