java - Android Random Number llegalArgumentException: n <= 0: 0 -


i trying generate random number 0 43 range. @ devices (oneplus android 5.0.2 , nexus 5.1) throwing java.lang.illegalargumentexception: n <= 0: 0. not able catch exception below code generate random number.

    random rand = new random();     int maximum = mlistofstrings.getmystring().size() - 1;     log.e("max",""+maximum);     mint.logevent("maximum", mintloglevel.error);     int randomnum;     try{         // randomnum = rand.nextint(43);         randomnum = rand.nextint(maximum);     }catch (illegalargumentexception e){         e.printstacktrace();         randomnum = 8;     }      log.e("random number", randomnum+"");

and log 

1   @ android.app.activitythread.performlaunchactivity(activitythread.java:2329) 2   @ android.app.activitythread.handlelaunchactivity(activitythread.java:2389) 3   @ android.app.activitythread.access$900(activitythread.java:147) 4   @ android.app.activitythread$h.handlemessage(activitythread.java:1296) 5   @ android.os.handler.dispatchmessage(handler.java:102) 6   @ android.os.looper.loop(looper.java:135) 7   @ android.app.activitythread.main(activitythread.java:5254) 8   @ java.lang.reflect.method.invoke(native method) 9   @ java.lang.reflect.method.invoke(method.java:372) 10  @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:898) 11  @ com.android.internal.os.zygoteinit.main(zygoteinit.java:693) 12caused by: java.lang.illegalargumentexception: n <= 0: 0 13  @ java.util.random.nextint(random.java:182) 14  @ com.algo.toiletbreak.shareactivity.oncreate(unknown source) 15  @ android.app.activity.performcreate(activity.java:5933) 16  @ android.app.instrumentation.callactivityoncreate(instrumentation.java:1105) 17  @ android.app.activitythread.performlaunchactivity(activitythread.java:2282) 18  ... 10 more

if nextint method complaining argument 0, maximum 0. implies mlistofstrings.getmystring().size() returned 1. there's no point in attempting generating random number 0 inclusive through 0 exclusive; such int doesn't exist. parameter value 1 more maximum random value can returned. means should not subtract 1 when assigning maximum.

int maximum = mlistofstrings.getmystring().size();

you may want test if size() method returns 0, , handle case specially.


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