A DESCRIPTION OF THE REQUEST :
Javac does not fully optimize the code when the concatenation with "+" is used.

JUSTIFICATION :
performance impoved by about 20% on the code provided below
(comparison between the 2 methods 'loopBasic' and 'loopStringBuilder')

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
//method provided below decompiled with jad SHOULD BE
    private String loopBasic(String s) {
        String s1 = new String();
        for(int i = 0; i < 0x989680; i++)
            s1 = (new StringBuilder("A")).append(s).append("C").toString();
        return s1.toString();
    }

ACTUAL -
//method provided below decompiled with jad
    private String loopBasic(String s) {
        String s1 = new String();
        for(int i = 0; i < 0x989680; i++)
            s1 = (new StringBuilder()).append("A").append(s).append("C").toString();
        return s1.toString();
    }


---------- BEGIN SOURCE ----------
//To compile, execute to get the performance result, to decompile with jad
public class StringBufferTest{
    
    private String loopBasic(String aString) {
        String essai = new String();
        for (int i =0 ; i<10000000 ; i++) {
             essai = "A" + aString + "C";
        }
        return essai.toString();
    }
    
    private String loopStringBuffer(String aString) {
        StringBuffer essai = new StringBuffer();
        for (int i =0 ; i<10000000 ; i++) {
             essai = new StringBuffer("A").append(aString).append("C");
        }
        return essai.toString();
    }

    private String loopStringBuilder(String aString) {
        StringBuilder essai = new StringBuilder();
        for (int i =0 ; i<10000000 ; i++) {
             essai = new StringBuilder("A").append(aString).append("C");
        }
        return essai.toString();
    }

    public static void main(String args[]){
        StringBufferTest stringBufferTest = new StringBufferTest();
        System.out.println("Start loopBasic : " + System.currentTimeMillis());
        System.out.println(stringBufferTest.loopBasic("string"));
        System.out.println("start loopStringBuffer : " + System.currentTimeMillis());
        System.out.println(stringBufferTest.loopStringBuffer("string"));
        System.out.println("Start loopStringBuilder : " + System.currentTimeMillis());
        System.out.println(stringBufferTest.loopStringBuffer("string"));
        System.out.println("End : " + System.currentTimeMillis());
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
obviously, use StringBuilder instead