I am trying to generate Random Number from 0 to 43 range. But at Some Devices (OnePlus Android 5.0.2 and Nexus 5.1) it is throwing java.lang.IllegalArgumentException: n <= 0: 0. I am not able to catch that exception Below is my Code to generate the 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 also Log is
1 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2329)
2 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2389)
3 at android.app.ActivityThread.access$900(ActivityThread.java:147)
4 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1296)
5 at android.os.Handler.dispatchMessage(Handler.java:102)
6 at android.os.Looper.loop(Looper.java:135)
7 at android.app.ActivityThread.main(ActivityThread.java:5254)
8 at java.lang.reflect.Method.invoke(Native Method)
9 at java.lang.reflect.Method.invoke(Method.java:372)
10 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898)
11 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
12Caused by: java.lang.IllegalArgumentException: n <= 0: 0
13 at java.util.Random.nextInt(Random.java:182)
14 at com.algo.toiletbreak.ShareActivity.onCreate(Unknown Source)
15 at android.app.Activity.performCreate(Activity.java:5933)
16 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
17 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2282)
18 ... 10 more
If the nextInt
method is complaining that its argument was 0
, then maximum
was 0
. That implies that mListofStrings.getMyString().size()
returned 1
. There's no point in attempting to generating a random number from 0
inclusive through 0
exclusive; such an int
doesn't exist. But the parameter value is one more than the maximum random value that can be returned. This means that you should not subtract 1
when assigning maximum
.
int maximum = mListofStrings.getMyString().size();
You may also want to test if the size()
method returns 0
, and handle that case specially.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With