Long.getLong() failing, returning null to valid string

Question

I've spent the past two hours debugging what seems extremely unlikely. I've stripped the method of a secondary Android Activity to exactly this:

public void onClick(View v) {
        String str = "25";
        long my_long = Long.getLong(str);
} // onClick (v)

And yeah, I get a crash with the good ol' NullPointerException:

09-11 02:02:50.444: ERROR/AndroidRuntime(1588): Uncaught handler: thread main exiting due to uncaught exception 09-11 02:02:50.464: ERROR/AndroidRuntime(1588): java.lang.NullPointerException

It looks like (from other tests) that Long.getLong(str) returns NULL, which is driving me bonkers. WHAT AM I MISSING?

Thanks in advance. I'm okay with stupidly missing the obvious, but my sanity is on the line.

score 12 · Accepted Answer · Sep 11 '11 at 18:36

up vote 12 down vote accepted

You are missing the fact that Long.getLong(String str) is not supposed to parse a String to a long, but rather to return a long value of a system property represented by that string. As others have suggested, what you actually need is Long.parseLong(String str).

edited Sep 11 '11 at 18:36

answered Sep 11 '11 at 8:28

MeLight
1,284 8 20

	Ahh, that makes perfect sense. Thanks! – Scott Biggs Sep 11 '11 at 16:57
	Very descriptive reply.+1 for that. – Android Killer Sep 11 '11 at 17:30
	Thanks and welcome :) – MeLight Sep 11 '11 at 18:35

Android Killer 4,419 2 10 35 · Answer 2 · Sep 11 '11 at 7:24

up vote 3 down vote

I think you are using wrong function use Long.parseLong(str) then you can get the right answer.

answered Sep 11 '11 at 7:24

Android Killer
4,419 2 10 35

	You are absolutely right. Thanks for the help! – Scott Biggs Sep 11 '11 at 18:52
	My pleasure to help u buddy. – Android Killer Sep 12 '11 at 2:26

score 3 · Answer 3 · Sep 11 '11 at 7:30

up vote 3 down vote

you can use Long.parsLong(String) instead of getLong(String) it will solve the problem

edited Sep 11 '11 at 7:30

answered Sep 11 '11 at 7:20

confucius
4,366 3 7 29

Thanks, the change worked! – Scott Biggs Sep 11 '11 at 18:52

Y.A.P. 247 1 6 · Answer 4 · Sep 11 '11 at 7:53

up vote 3 down vote

Long.parseLong(someString) approved. Don't forget to catch NumberFormatException if there's a probability of unparsable string.

answered Sep 11 '11 at 7:53

Y.A.P.
247 1 6

Yes, thank you! Wasn't thinking along those lines. – Scott Biggs Sep 11 '11 at 16:58

解决java的Long.getLong(str)的NullPointerException错误

Long.getLong() failing, returning null to valid string

4 Answers

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