Re: Which is more efficient?

From: metfan (qjzhupublic_at____NoSpam__yahoo.ie)
Date: 10/24/03 

Date: Fri, 24 Oct 2003 16:21:25 +0800

>> For the following to snips, which one do you think is more efficient?
>>
>> snip1:
>> BufferedWriter bw = new BufferedWriter(new
>> OutputStreamWriter(System.out));
>> bw.write("abc" + "def");
>>
>> snip2:
>> BufferedWriter bw = new BufferedWriter(new
>> OutputStreamWriter(System.out));
>> bw.write("abc");
>> bw.write("def");
>
> The first, as it compiles to the same as:
>
> BufferedWriter bw = new BufferedWriter(new
> OutputStreamWriter(System.out));
> bw.write("abcdef");
>
> because literal strings are concatenated at compile time.
>

   Well.. what if:

snip1:
          BufferedWriter bw = new BufferedWriter(new
OutputStreamWriter(System.out));
        String a = new String("abc");
        String b = new String("def");
          bw.write(a + b);

snip2:
          BufferedWriter bw = new BufferedWriter(new
OutputStreamWriter(System.out));
        String a = new String("abc");
        String b = new String("def");
          bw.write(a);
          bw.write(b); 

-- 
Best regards,
Qingjia Zhu
Q@z@J

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