<Swing Dev> Replace concat String to append in StringBuilder parameters

[Pavel Rappo]

It's exactly the way it's been working since 1.6 I believe.

<source>

public class Optimization {

    public String concat(String... strings) {
        return "#: " + strings[0] + strings[2] + strings[3] + "...";
    }
}

<compiled into>

public class Optimization {
  public Optimization();
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return

  public java.lang.String concat(java.lang.String...);
    Code:
       0: new           #2                  // class java/lang/StringBuilder
       3: dup
       4: invokespecial #3                  // Method java/lang/StringBuilder."<init>":()V
       7: ldc           #4                  // String #:
       9: invokevirtual #5                  // Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
      12: aload_1
      13: iconst_0
      14: aaload
      15: invokevirtual #5                  // Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
      18: aload_1
      19: iconst_2
      20: aaload
      21: invokevirtual #5                  // Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
      24: aload_1
      25: iconst_3
      26: aaload
      27: invokevirtual #5                  // Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
      30: ldc           #6                  // String ...
      32: invokevirtual #5                  // Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
      35: invokevirtual #7                  // Method java/lang/StringBuilder.toString:()Ljava/lang/String;
      38: areturn
}

-Pavel

On 26 Aug 2014, at 06:20, Xuelei Fan <xuelei.fan at oracle.com> wrote:

> I was wondering, is it nice to address it in Java compiler to use string
> builder for the string "+" operator?
> 
> Xuelei
> 
> 
> On 8/26/2014 11:28 AM, Wang Weijun wrote:
>> New webrevs available at
>> 
>>  http://cr.openjdk.java.net/~weijun/8055723/client/webrev.01/
>>  http://cr.openjdk.java.net/~weijun/8055723/core/webrev.01/  
>> 
>> There are only 2 now. Everything non-client is in core.
>> 
>> Everyone, please do code review quickly because the patch touches too many files and any delay could mean re-merge.
>> 
>> *Otávio*: If there is only small change in feedback, tell me to update my own repo and you don't need to generate the big patch again.
>> 
>> I see you still include that demo file.
>> 
>> Thanks
>> Max
>> 
>> 
>