动态创建XML节点的XSLT需求：补全缺失层级子节点

To solve this problem, we need to ensure every AWARDLINE node has the full hierarchy of SHIPMENT → ACCOUNT → ASSOCIATEDREQ nodes, creating empty nodes for any missing levels. Here's a straightforward XSLT implementation that handles each layer of the hierarchy:

Source XML #

<AWARD> 
  <FIELD1>XYZ</FIELD1> 
  <AWARDLINE> 
    <ALINENUM>1</ALINENUM> 
    <SHIPMENT> 
      <SHIPLINENUM>1.1</SHIPLINENUM> 
      <ACCOUNT> 
        <ACCOUNTLINENUM>1.1.1</ACCOUNTLINENUM> 
        <ASSOCIATEDREQ> 
          <AREQNUM>1.1.1.1</AREQNUM> 
        </ASSOCIATEDREQ> 
      </ACCOUNT> 
    </SHIPMENT> 
  </AWARDLINE> 
  <AWARDLINE> 
    <ALINENUM>2</ALINENUM> 
  </AWARDLINE> 
</AWARD>

Desired Output XML #

<AWARD> 
  <FIELD1>XYZ</FIELD1> 
  <AWARDLINE> 
    <ALINENUM>1</ALINENUM> 
    <SHIPMENT> 
      <SHIPLINENUM>1.1</SHIPLINENUM> 
      <ACCOUNT> 
        <ACCOUNTLINENUM>1.1.1</ACCOUNTLINENUM> 
        <ASSOCIATEDREQ> 
          <AREQNUM>1.1.1.1</AREQNUM> 
        </ASSOCIATEDREQ> 
      </ACCOUNT> 
    </SHIPMENT> 
  </AWARDLINE> 
  <AWARDLINE> 
    <ALINENUM>2</ALINENUM> 
    <SHIPMENT> 
      <ACCOUNT> 
        <ASSOCIATEDREQ/> 
      </ACCOUNT> 
    </SHIPMENT> 
  </AWARDLINE> 
</AWARD>

XSLT Code #

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <!-- Identity template: copy all existing nodes/attributes as-is -->
    <xsl:template match="@*|node()">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()"/>
        </xsl:copy>
    </xsl:template>

    <!-- Ensure AWARDLINE has a SHIPMENT node (create empty if missing) -->
    <xsl:template match="AWARDLINE">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()"/>
            <xsl:if test="not(SHIPMENT)">
                <SHIPMENT>
                    <xsl:apply-templates select="SHIPMENT/@*|SHIPMENT/node()"/>
                </SHIPMENT>
            </xsl:if>
        </xsl:copy>
    </xsl:template>

    <!-- Ensure SHIPMENT has an ACCOUNT node (create empty if missing) -->
    <xsl:template match="SHIPMENT">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()"/>
            <xsl:if test="not(ACCOUNT)">
                <ACCOUNT>
                    <xsl:apply-templates select="ACCOUNT/@*|ACCOUNT/node()"/>
                </ACCOUNT>
            </xsl:if>
        </xsl:copy>
    </xsl:template>

    <!-- Ensure ACCOUNT has an ASSOCIATEDREQ node (create empty if missing) -->
    <xsl:template match="ACCOUNT">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()"/>
            <xsl:if test="not(ASSOCIATEDREQ)">
                <ASSOCIATEDREQ/>
            </xsl:if>
        </xsl:copy>
    </xsl:template>
</xsl:stylesheet>

How It Works #

• Identity Template: This is the base template that copies all existing XML content exactly as it is, preserving nodes and attributes that are already present.
• AWARDLINE Template: Checks if the AWARDLINE has a SHIPMENT child. If not, it creates an empty SHIPMENT node and applies templates to any existing (though in this case, none) content inside it.
• SHIPMENT Template: Similarly, checks for an ACCOUNT child. If missing, creates an empty ACCOUNT node.
• ACCOUNT Template: Checks for an ASSOCIATEDREQ child. If missing, creates an empty ASSOCIATEDREQ node.

This layered approach ensures that every level of the hierarchy is completed, regardless of which nodes are missing in the source XML. It works for any combination of missing nodes (e.g., AWARDLINE has SHIPMENT but no ACCOUNT, or ACCOUNT exists but no ASSOCIATEDREQ).

内容的提问来源于stack exchange，提问作者Nagaraj Rao