NPE in toString method of generated decoder #708
Description
It seems java codegen tool not fully aware of optional fields. We are getting NPE during decode our new traceContext2 field. This field is available since version 3 of our schema and marked as optional.
<field xmlns="" name="traceContext2" id="4" type="TraceContext" description="Distributed Trace Context" presence="optional" sinceVersion="3"/>
If we will try to send message with version 2 and call toString we will obtain an NPE
Reported exception:
java.lang.NullPointerException
at com.mlp.ctp.generic.MessageAckDecoder.appendTo(MessageAckDecoder.java:352)
at com.mlp.ctp.generic.MessageAckDecoder.toString(MessageAckDecoder.java:308)
Generated code:
toString:
builder.append('|');
builder.append("traceContext2=");
this.traceContext2().appendTo(builder);
traceContext2() method:
public TraceContextDecoder traceContext2() {
if (this.parentMessage.actingVersion < 3) {
return null;
} else {
this.traceContext2.wrap(this.buffer, this.offset + 16);
return this.traceContext2;
}
}