equals() in StringBuffer

[Chinmay Bajikar]

Hi,
Have a look at this code snippet,

 
public class TestStringBuf
{
public static void main(String[] args) 
{
StringBuffer sbuf =  new StringBuffer("XYZ"); 
StringBuffer dbuf =  new StringBuffer("XYZ"); 

if(sbuf.equals(dbuf)){                      
System.out.println("sbuf==dbuf");               
}else{                                          
System.out.println("sbuf!=dbuf");               
}     
 
}
}

What should ideally happen?
I didnt find any equals() implementation in the StringBuffer class.
I am using JDK 1.4.2.

[Chinmay Bajikar]

Sorry, but I should have serached the forum for similar topics first.
Found what I was looking for here,
Answer

Was curious to know if there is any specific reason for not overriding equals() in StringBuffer.

Thanks and sorry for the inconvinience,
Chinmay.

[Ernest Friedman-Hill]

I would imagine it was just an oversight. Remember the curious fact that the oldest classes in the Java APIs were written by people who had no experience at all writing in Java!

[Ilja Preuss]

Originally posted by Ernest Friedman-Hill:
I would imagine it was just an oversight. Remember the curious fact that the oldest classes in the Java APIs were written by people who had no experience at all writing in Java!

And apparently also not in other OO languages... :roll:

[pascal betz]

but StringBuilder (added in 1.5) also does not override equals()...

any other reasons (appart from "just forgotten") ?

cheers

pascal

[Ilja Preuss]

Originally posted by pascal betz:
but StringBuilder (added in 1.5) also does not override equals()...

They probably wanted it to be as compatible to StringBuffer as possible...

[Ilja Preuss]

http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5082260 explains it all.

[pascal betz]

who needs Map anyway :-)

thanks for the link.

pascal

[bala rajesh]

Originally posted by Chinmay Bajikar:
Hi,
Have a look at this code snippet,

 
public class TestStringBuf
{
public static void main(String[] args) 
{
StringBuffer sbuf =  new StringBuffer("XYZ"); 
StringBuffer dbuf =  new StringBuffer("XYZ"); 

if(sbuf.equals(dbuf)){                      
System.out.println("sbuf==dbuf");               
}else{                                          
System.out.println("sbuf!=dbuf");               
}     
 
}
}

What should ideally happen?
I didnt find any equals() implementation in the StringBuffer class.
I am using JDK 1.4.2.

Answer
------


== symbols used to compare the content(string)in a object.
but .equals()method is used to compare the string or stringbuffer object;
so sbuf,dbuf or different object, so that the result is sbuf!=dbuf

[Ilja Preuss]

Originally posted by bala rajesh:
== symbols used to compare the content(string)in a object.
but .equals()method is used to compare the string or stringbuffer object;
so sbuf,dbuf or different object, so that the result is sbuf!=dbuf

Huh? For StringBuffer objects, == and equals() do exactly the same thing, because StringBuffer doesn't override equals() (in contrast to String). The original poster asked about the reasoning for this, and I think the previous responses were right on mark. Therefore your responses confuses me quite a bit...