When I am submitting XML feed using amazon SP API I am facing error XML Parsing Fatal Error

Question

• FEED

  <?xml version="1.0" encoding="utf-8" ?>
    <AmazonEnvelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="amzn-envelope.xsd">
      <Header>
        <DocumentVersion>1.01</DocumentVersion>
        <MerchantIdentifier>SellerId</MerchantIdentifier>
      </Header>
      <MessageType>Inventory</MessageType>
      <Message>
        <MessageID>1</MessageID>
        <OperationType>Update</OperationType>
        <Inventory>
          <SKU>SKUIID1223</SKU>
          <Quantity>4</Quantity>
        </Inventory>
      </Message>
    </AmazonEnvelope>
  

ERROR : XML Parsing Fatal Error at Line 1, Column 1: Content is not allowed in prolog. Content is not allowed in prolog.

<?xml version="1.0" encoding="UTF-8"?>
<AmazonEnvelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="amzn-envelope.xsd">
    <Header>
        <DocumentVersion>1.02</DocumentVersion>
        <MerchantIdentifier>A2ICRN18O3Y4N7</MerchantIdentifier>
    </Header>
    <MessageType>ProcessingReport</MessageType>
    <Message>
        <MessageID>1</MessageID>
        <ProcessingReport>
            <DocumentTransactionID>257173019690</DocumentTransactionID>
            <StatusCode>Complete</StatusCode>
            <ProcessingSummary>
                <MessagesProcessed>0</MessagesProcessed>
                <MessagesSuccessful>0</MessagesSuccessful>
                <MessagesWithError>1</MessagesWithError>
                <MessagesWithWarning>0</MessagesWithWarning>
            </ProcessingSummary>
            <Result>
                <MessageID>0</MessageID>
                <ResultCode>Error</ResultCode>
                <ResultMessageCode>5001</ResultMessageCode>
                <ResultDescription>XML Parsing Fatal Error at Line 1, Column 1: Content is not allowed in prolog. Content is not allowed in prolog.</ResultDescription>
            </Result>
        </ProcessingReport>
    </Message>
</AmazonEnvelope>

Answer 1

It may be a problem with space characters in the buffer below. Check the contents below, parse the xml contents, and send it.

String xml = "<?xml ...";
xml = xml.trim().replaceFirst("^([\\W]+)<","<");