FULL PRODUCT VERSION :
java version "1.5.0_02"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_02-b09)
Java HotSpot(TM) Client VM (build 1.5.0_02-b09, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows 2000 [Version 5.00.2195]

A DESCRIPTION OF THE PROBLEM :
Encoding a string to a byte array results in the follows. All chars are ascii (in this case the letter 'a') and the encoding is utf-8.

A string of 1-9 characters results in the same # of bytes.

A string of 10-19 chars results in a single additional nulls at the end of the byte array.

A string of 20-29 chars results in two null and so on.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run this simple class below.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expected the # of chars and the # of bytes to be the same.
ACTUAL -
Here's some samples:

String length=10 bytes length=11
  a a a a a a a a a a
 97 97 97 97 97 97 97 97 97 97 0


String length=11 bytes length=12
  a a a a a a a a a a a
 97 97 97 97 97 97 97 97 97 97 97 0

String length=19 bytes length=20
  a a a a a a a a a a a a a a a a a a a
 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 0


String length=20 bytes length=22
  a a a a a a a a a a a a a a a a a a a a
 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 0 0




REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------

import java.nio.*;
import java.nio.charset.*;

public class EncodingTest {
    
    public static String createTestString(int len,char charval) {
        StringBuffer sb = new StringBuffer();
        for (int i=0; i < len; i++) {
            sb.append(charval);
        }
        return sb.toString();
    }
    
    public static void doEncodingTest(int len,char charval) {
        try {
            String val = createTestString(len,charval);
            Charset cs = Charset.forName("utf-8");
            CharsetEncoder cse = cs.newEncoder();
            char[] chars = val.toCharArray();
            CharBuffer cb = CharBuffer.wrap(chars);
            ByteBuffer bb = cse.encode(cb);
            cse.flush(bb);
            byte[] bytes = bb.array();
            if (val.length() != bytes.length) {
                System.out.println("String length=" + val.length() + " bytes length=" + bytes.length);
                for (int i = 0; i < val.length(); i++) {
                    System.out.print(" " + val.charAt(i));
                }
                System.out.println("");
                for (int i = 0; i < bytes.length; i++) {
                    System.out.print(" " + bytes[i]);
                }
                System.out.println("");
            }
        } catch(CharacterCodingException e) {
            System.out.println(e.toString());
        }
        System.out.println("");
    }
    
    public static void doEncodingTests(int max,char charval) {
        for (int i = 1; i <= max; i++) {
            doEncodingTest(i,charval);
            System.out.println("");
        }
    } public static void main(String[] args) {
        doEncodingTests(30,'a');
    }
    
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
I strip null chars off the end, which adds overhead. The above case is a gross
simplification meant to show the problem.
###@###.### 2005-03-23 22:52:14 GMT