code: @Override
      public void writeByte(byte value) throws JMSException {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "writeByte", value);
  
          try {
              // Check if the producer has promised not to modify the payload after it's been set
              checkProducerPromise("writeByte(byte)", "JmsBytesMessageImpl.writeByte#2");
  
              // Check that we are in write mode
              checkBodyWriteable("writeByte");
  
              // Write the byte to the output stream
              writeStream.writeByte(value);
  
              // Invalidate the cached toString object.
              cachedBytesToString = null;
  
              // Ensure that the new data gets exported when the time comes.
              bodySetInJsMsg = false;
          }
  
          // We don't expect the writeByte to fail, but we need to catch the exception anyway
          catch (IOException ex) {
              // No FFDC code needed
              // d238447 review. Generate FFDC for this case.
              throw (JMSException) JmsErrorUtils.newThrowable(
                                                              ResourceAllocationException.class,
                                                              "WRITE_PROBLEM_CWSIA0186",
                                                              null,
                                                              ex,
                                                              "JmsBytesMessageImpl.writeByte#1",
                                                              this,
                                                              tc);
          }
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "writeByte");
      }
docs: Write out a <code>byte</code> to the stream message as a 1-byte value.
  
  @param value the <code>byte</code> value to be written.
  
  @exception MessageNotWriteableException if message in read-only mode.
  @exception JMSException if JMS fails to write message due to
  some internal JMS error.