java - Why must I use try catch when I use global exception handling? -


i'm beginner in java , android. problem when use setdefaultuncaughtexceptionhandler in code, functions still need try/catch block surrounding it, want throw exceptions uncaughtexception thread.

    public class myalarmreciever  extends broadcastreceiver {     @override     public void onreceive(context context, intent intent)     {         thread.setdefaultuncaughtexceptionhandler(new uncaughtexception(context));          try         {                string imageurl = mywebservice.readfeed();             downloadandset.downloadfile(imageurl);           }         catch(throwable e)         {                        throw new runtimeexception(e);                   }          toast.maketext(context, "alarm triggered", toast.length_long).show();       } }

java distinguishes checked , unchecked exceptions. checked exceptions have to caught, no matter what.

correction: or have add throws clause method. postpones urge catch exception caller of method.

if want them handled in uncaughtexceptionhandler, can "forward" them:

try{     // blah "throws checked exception type" } catch ( throwable e ) {     // throw e; <- not work :( unless add "throws" clause.     throw new runtimeexception(e); }

unfortunately, throwing same exception won't work, because you'd have add throws clause, not want. you'll have wrap in runtimeexception.


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