Need El Help-o - Topic

Calamitymic

Member

Posts: 15,666

Joined: Jul 15 2007

Gold: 3,046.40

#11

Jul 31 2012 06:08pm

Quote (SilverMice @ Jul 31 2012 04:03pm)

print out what is being compared and see if you can figure out the issue.

Strange...

Code

boolean leave=false;

for(i=0; i<namesArr.size();i++){

if(leave==false){
if((usTemp==namesArr.get(i) && pwTemp==passArr.get(i))){

System.out.println("Welcome!");
leave=true;

}else{
System.out.print(usTemp + " == " + namesArr.get(i) + " && " + pwTemp + " == " + passArr.get(i) + " ");
System.out.println("User does not exist");
}
}
}

Results:

Code

asdf == can't && asdf == pan't User does not exist
asdf == asdf && asdf == asdf User does not exist
asdf == df && asdf == df User does not exist
asdf == asdf && asdf == asdf User does not exist

SilverMice

Member

Posts: 5,641

Joined: Apr 13 2006

Gold: 2.00

#12

Jul 31 2012 06:12pm

you can get rid of the leave boolean.

Also the reason seems to be == I would guess in java does an address test. .Equals() should do the trick.

Code

for(i=0; i<namesArr.size();i++){

if((usTemp.Equals(namesArr.get(i)) && pwTemp.Equals(passArr.get(i)))){

System.out.println("Welcome!");

}else{
System.out.println("User does not exist");
}

}

This post was edited by SilverMice on Jul 31 2012 06:13pm

Calamitymic

Member

Posts: 15,666

Joined: Jul 15 2007

Gold: 3,046.40

#13

Jul 31 2012 06:16pm

i love you man.

rockonkenshin

Member

Posts: 11,637

Joined: Feb 2 2004

Gold: 434.84

#14

Aug 1 2012 08:19am

Quote (SilverMice @ Jul 31 2012 07:12pm)

you can get rid of the leave boolean.

Also the reason seems to be == I would guess in java does an address test. .Equals() should do the trick.

Code

for(i=0; i<namesArr.size();i++){

if((usTemp.Equals(namesArr.get(i)) && pwTemp.Equals(passArr.get(i)))){

System.out.println("Welcome!");

}else{
System.out.println("User does not exist");
}

}

For objects in Java '==' does an instance equality check, i.e. it checks if the two objects are the same instance. This can be particularly nasty with Strings as sometimes String literals will pass that check due to Java's String interning. Always use Object.equals(Object o) when checking the equality unless for some reason you need to make sure the instances are the same.

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