code: public void println(char c) throws IOException
      {  
          if(this._listener!= null &&  !checkIfCalledFromWLonError()){
  
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())    
                  Tr.debug(tc, "non blocking println char , WriteListener enabled: " + this._listener);
              _outHelper.println_NonBlocking(Character.toString(c));
          }
          else {
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())    
                  Tr.debug(tc, "println char");
              this.singleByte[0] = (byte) c;
              synchronized(this) {
                  this.write(this.singleByte, 0, 1);
                  this.write(CRLF, 0, 2);
              }
          }
      }
docs: /*
  @see javax.servlet.ServletOutputStream#println(char)