XSLT 1.0: rename elements with same content

问题:

It seemed like an easy task but I am totally stuck now. I have the following XML:

<?xml version="1.0" encoding="UTF-8"?>
<Items>
<Item>
    <ITEM_CODE>ITEM_CODE</ITEM_CODE>
    <ITEM_NAME>ITEM_NAME</ITEM_NAME>
    <ITEM_ALTERNATE_NAME>ITEM_ALTERNATE_NAME</ITEM_ALTERNATE_NAME>
    <ITEM_CATEGORY_CODE>ITEM_CATEGORY_CODE</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>15031</ITEM_CODE>
    <ITEM_NAME>Outer Carton</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150529</ITEM_CODE>
    <ITEM_NAME>Outer Carton</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150999</ITEM_CODE>
    <ITEM_NAME>Outer Carton</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150988</ITEM_CODE>
    <ITEM_NAME>test</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
</Items>

If <ITEM_NAME> elements have duplicate contents those should be renamed with a suffix, e.g. a counter value. I came up with this XSLT:

<?xml version="1.0" encoding="UTF-8"?>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">

<xsl:output encoding="UTF-8" method="xml" indent="yes"/>

<xsl:key name="keyItemName" match="Item" use="concat(ITEM_CODE , '|', ITEM_NAME)"/>

<xsl:template match="@*|node()">
    <xsl:copy>
        <xsl:apply-templates select="@*|node()"/>
    </xsl:copy>
</xsl:template>

<xsl:template match="Items">
    <Items>
        <xsl:apply-templates select="@*|node()"/>
    </Items>    
</xsl:template>

<xsl:template match="ITEM_NAME">

    <xsl:for-each select="parent::Item[generate-id()=generate-id(key('keyItemName',concat(ITEM_CODE , '|', ITEM_NAME))[1])]">
        <xsl:variable name="number">
            <xsl:number/>
        </xsl:variable>
        <ITEM_NAME>
            <xsl:value-of select="concat(ITEM_NAME,'-',$number)"/>
        </ITEM_NAME>
    </xsl:for-each>
</xsl:template>

</xsl:stylesheet>

It gives me this output:

<?xml version="1.0" encoding="UTF-8"?>
<Items>
<Item>
    <ITEM_CODE>ITEM_CODE</ITEM_CODE>
    <ITEM_NAME>ITEM_NAME-1</ITEM_NAME>
    <ITEM_ALTERNATE_NAME>ITEM_ALTERNATE_NAME</ITEM_ALTERNATE_NAME>
    <ITEM_CATEGORY_CODE>ITEM_CATEGORY_CODE</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>15031</ITEM_CODE>
    <ITEM_NAME>Outer Carton-2</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150529</ITEM_CODE>
    <ITEM_NAME>Outer Carton-3</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150999</ITEM_CODE>
    <ITEM_NAME>Outer Carton-4</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150988</ITEM_CODE>
    <ITEM_NAME>test-5</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
</Items>

But I expect this output:

<?xml version="1.0" encoding="UTF-8"?>
<Items>
<Item>
    <ITEM_CODE>ITEM_CODE</ITEM_CODE>
    <ITEM_NAME>ITEM_NAME</ITEM_NAME>
    <ITEM_ALTERNATE_NAME>ITEM_ALTERNATE_NAME</ITEM_ALTERNATE_NAME>
    <ITEM_CATEGORY_CODE>ITEM_CATEGORY_CODE</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>15031</ITEM_CODE>
    <ITEM_NAME>Outer Carton-2</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150529</ITEM_CODE>
    <ITEM_NAME>Outer Carton-3</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150999</ITEM_CODE>
    <ITEM_NAME>Outer Carton-4</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
<Item>
    <ITEM_CODE>150988</ITEM_CODE>
    <ITEM_NAME>test</ITEM_NAME>
    <ITEM_ALTERNATE_NAME/>
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
</Item>
</Items>

In the last <Item> the ITEM_NAME should not be renamed because it is not called "Outer Carton". Also in the first <Item> element no renaming should be happening.

I am close to the solution but I just can't get around to it. Can someone please help - thanks a lot!

Best regards, Peter

回答1:

You current key seems to join ITEM_NAME and ITEM_CODE, but it looks like you only want ITEM_NAME here

<xsl:key name="keyItemName" match="ITEM_NAME" use="."/>

It also looks like you want the numbering for the suffix to be based on the position of the parent item element. One way to achieve this is to have a template to match the item element, and then pass the number as a parameter to the subsequent mathching templates

<xsl:template match="Item">
   <Item>
      <xsl:apply-templates select="@*|node()">
          <xsl:with-param name="number">
            <xsl:number/>
         </xsl:with-param>
      </xsl:apply-templates>
   </Item>
</xsl:template>

Then, you need a template to match ITEM_NAME elements for which duplicate occurs. This can be done simply by checking there is at least a second element defined in the group for the key:

<xsl:template match="ITEM_NAME[key('keyItemName', .)[2]]">
   <xsl:param name="number"/>

Then, you can just output the element with the suffix.

Here is the full XSLT

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
   <xsl:output encoding="UTF-8" method="xml" indent="yes"/>

   <xsl:key name="keyItemName" match="ITEM_NAME" use="."/>

   <xsl:template match="@*|node()">
      <xsl:copy>
         <xsl:apply-templates select="@*|node()"/>
      </xsl:copy>
   </xsl:template>

   <xsl:template match="Item">
      <Item>
         <xsl:apply-templates select="@*|node()">
            <xsl:with-param name="number">
               <xsl:number/>
            </xsl:with-param>
         </xsl:apply-templates>
      </Item>
   </xsl:template>

   <xsl:template match="ITEM_NAME[key('keyItemName', .)[2]]">
      <xsl:param name="number"/>
      <ITEM_NAME>
         <xsl:value-of select="concat(.,'-',$number)"/>
      </ITEM_NAME>
   </xsl:template>
</xsl:stylesheet>

When applied to your XML, the following is output

<Items>
   <Item>
      <ITEM_CODE>ITEM_CODE</ITEM_CODE>
      <ITEM_NAME>ITEM_NAME</ITEM_NAME>
      <ITEM_ALTERNATE_NAME>ITEM_ALTERNATE_NAME</ITEM_ALTERNATE_NAME>
      <ITEM_CATEGORY_CODE>ITEM_CATEGORY_CODE</ITEM_CATEGORY_CODE>
   </Item>
   <Item>
      <ITEM_CODE>15031</ITEM_CODE>
      <ITEM_NAME>Outer Carton-2</ITEM_NAME>
      <ITEM_ALTERNATE_NAME/>
      <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
   </Item>
   <Item>
      <ITEM_CODE>150529</ITEM_CODE>
      <ITEM_NAME>Outer Carton-3</ITEM_NAME>
      <ITEM_ALTERNATE_NAME/>
      <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
   </Item>
   <Item>
      <ITEM_CODE>150999</ITEM_CODE>
      <ITEM_NAME>Outer Carton-4</ITEM_NAME>
      <ITEM_ALTERNATE_NAME/>
      <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
   </Item>
   <Item>
      <ITEM_CODE>150988</ITEM_CODE>
      <ITEM_NAME>test</ITEM_NAME>
      <ITEM_ALTERNATE_NAME/>
      <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
   </Item>
</Items>

回答2:

Using preceding:: or preceding-sibling:: to count prior instances is not very efficient computationally, but I don't see a way around it here. The approach below does have the benefit that it only counts preceding instances when after checking (with a key, which is very quick) that there are other items with the same name:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output encoding="UTF-8" method="xml" indent="yes"/>

  <xsl:key name="keyItemName" match="ITEM_NAME" use="."/>

  <xsl:template match="@*|node()">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="Items">
    <Items>
      <xsl:apply-templates select="@*|node()"/>
    </Items>
  </xsl:template>

  <xsl:template match="ITEM_NAME">
    <xsl:copy>
      <xsl:value-of select="." />
      <xsl:if test="count(key('keyItemName', .)) > 1">
        <xsl:value-of select="concat('-', count(preceding::ITEM_NAME[. = current()]) + 2)"/>
      </xsl:if>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

When run on your sample input, this produces:

<Items>
  <Item>
    <ITEM_CODE>ITEM_CODE</ITEM_CODE>
    <ITEM_NAME>ITEM_NAME</ITEM_NAME>
    <ITEM_ALTERNATE_NAME>ITEM_ALTERNATE_NAME</ITEM_ALTERNATE_NAME>
    <ITEM_CATEGORY_CODE>ITEM_CATEGORY_CODE</ITEM_CATEGORY_CODE>
  </Item>
  <Item>
    <ITEM_CODE>15031</ITEM_CODE>
    <ITEM_NAME>Outer Carton-2</ITEM_NAME>
    <ITEM_ALTERNATE_NAME />
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
  </Item>
  <Item>
    <ITEM_CODE>150529</ITEM_CODE>
    <ITEM_NAME>Outer Carton-3</ITEM_NAME>
    <ITEM_ALTERNATE_NAME />
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
  </Item>
  <Item>
    <ITEM_CODE>150999</ITEM_CODE>
    <ITEM_NAME>Outer Carton-4</ITEM_NAME>
    <ITEM_ALTERNATE_NAME />
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
  </Item>
  <Item>
    <ITEM_CODE>150988</ITEM_CODE>
    <ITEM_NAME>test</ITEM_NAME>
    <ITEM_ALTERNATE_NAME />
    <ITEM_CATEGORY_CODE>52401</ITEM_CATEGORY_CODE>
  </Item>
</Items>