why the xa transaction does not work?

[gejing1108]

version: 5.4.1

<dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>shardingsphere-jdbc-core</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>shardingsphere-transaction-xa-core</artifactId>
        </dependency>

I've followed the github step to generate the examples for shardingsphere

and in this example, it runs the named run method to implement xa transaction, while I don't find any annotation on this method, this method only create table, insert records and then drop tables, so I doubt if it can show the function of xa transaction, I've tested in my way:
first, add the transaction type in config file as the sample do:

and then add the bean class as the sample do:

and then import it as the sample do:

and at last, I write a simple method to test it:

@Operation(summary = "测试XA事务")
  @PostMapping("/saveContractForXA")
  public ResponseResult<Void> saveContractForXA() {
    for (int i = 0; i < 10; i++) {
      if (i == 6) {
        int j = 8 / 0;
      }

      ContractEntity contract = new ContractEntity();
      contract.setContractName(RandomUtil.randomString(8));
      contractMapper.insert(contract);
    }

    return ResponseResult.success();
  }

in this method, I throw an exception when I've inserted 6 records, if the xa transaction works, it will rollback when the exception appears, while actually, 6 records are inserted into the table, so what have I omitted for xa transaction?

btw: in old version of shardingsphere like 4.X, I should add annotation like @ShardingTransactionType(value = TransactionType.XA), while in the 5.X version, I don't find this annotation, and in the sample generated above, I don't find any annotation on the method