Java String.equals()

[shababhsiddique]

I am having trouble with the String.equals(String) function


well here is what i am doing.

origin is fetched from a vector which was filled up by reading a text file.

answer is from standard input. readline()


i have to match the two words and see if they are equal.

origin.equals(answer)



boolean match=true;
for (int index = 0; index < answer.length(); index++) {
if(answer.charAt(index)!=origin.charAt(index))
{
match=false;
}
}
System.out.println(match);
System.out.println(answer.equals(origin));


match= true
but
answer.equals(origin)=false


what is wrong?

does the readline() add any /r or something at the end?

[Some Penguin]

Step through your code.

What does your code do if answer = "Blarg blarg" and origin = "Blarg"? And what does it do if we switch those?

[shababhsiddique]

here is the vector construction

Vector<String> respList = new Vector<String>();
do
{
// String reader;

i= fin.read();
if(i>-1){

if((char)i=='\n'){
respList.add(s);
s="";
// System.out.println();
}
else
{
// System.out.print((char)i);
s=s+(char)i;
}

}

}while(i!=-1);

[Some Penguin]

One, use 'code' tags. Two, there were obvious errors even in your first post that should be easily noticed if you use the pair of inputs I suggested. Even simpler, use 'AB' and 'A'.

[shababhsiddique]

Step through your code.

What does your code do if answer = "Blarg blarg" and origin = "Blarg"? And what does it do if we switch those?


its still says false

[Some Penguin]

Not when origin is shorter than answer, it won't. Your code will die with an exception.

[shababhsiddique]

boolean match=(answer.length()==origin.length());
for (int index = 0; index < answer.length(); index++) {

if(answer.charAt(index)!=origin.charAt(index))
{
match=false;
}
}


anyway i dont want to use this loop. I want to use answer.equals(origin)

[shababhsiddique]

Step through your code.

What does your code do if answer = "Blarg blarg" and origin = "Blarg"? And what does it do if we switch those?


I just noticed something when stepping through.
The length of answer is as expected but the length of origin is +1
perhaps a special character is added.

How do i resize it?

[shababhsiddique]

from debug watches i see

answer contains "oracle"

origin contains "oracle\r"

[schauerlich]

Stop coding. Write down the algorithm in pseudocode. Follow it precisely by hand on the inputs Some Penguin has suggested. Once you figure out why it doesn't work, go back and fix your code.

[shababhsiddique]

Not when origin is shorter than answer, it won't. Your code will die with an exception.

yes it shall die with exception. Plz help me

[Some Penguin]

Instead of trying to use an input stream like that, directly, have a look at BufferedReader's readLine() to read... entire lines at a time. And Vector is replaceable in many cases by ArrayList, since often you don't need the synchronization overhead of Vector.

[shababhsiddique]

Thanks all you guys. I am newbie in java so sorry to bother with so easy things.

Anyway problem is solved.

I wasnt expecting the lines include a carriage return \r

This made the strings not equal.