How can I call a method on a Java instance passed into XSLT?

Question

I need to have XSLT call a method on a Java instance that I pass as a parameter. So far I can only get it to work if I create the instance in the XSLT itself. If I attempt to call it on the passed instance it fails with

Exception in thread "main" javax.xml.transform.TransformerConfigurationException: 
Cannot find external method 'Test.get' (must be public).

I can prove the instance is being passed ok by outputting it (it comes out as the toString). Here is my Java:

public class Test {

    public static void main(String[] args) throws Exception {
        Transformer transformer = TransformerFactory.newInstance()
            .newTransformer(
            new StreamSource(Test.class.getResourceAsStream("test.xsl")));
        transformer.setParameter("test1", new Test());
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        transformer.transform(new StreamSource(
            new ByteArrayInputStream(
            "<?xml version=\"1.0\"?><data></data>".getBytes())),
            new StreamResult(outputStream));
        System.out.println(outputStream.toString());
    }

    public String get() {
        return "hello";
    }

    @Override
    public String toString() {
        return "An instance of Test";
    }
}

and here is my xsl:

<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:test="xalan://Test"
                exclude-result-prefixes="test"
>

    <xsl:param name="test1" />
    <xsl:variable name="test2" select="$test1"/>
    <xsl:variable name="test3" select="test:new()"/>

    <xsl:template match="/">
        <data>
            <!-- proves that the instance is really being passed -->
            <xsl:value-of select="$test1"/>
        </data>
        <data>
            <!-- first two do not work -->
            <!--<xsl:value-of select="test:get($test1)"/>-->
            <!--<xsl:value-of select="test:get($test2)"/>-->
            <!-- this one does work -->
            <xsl:value-of select="test:get($test3)"/>
        </data>
    </xsl:template>
</xsl:stylesheet>

Does anyone know how I can make this work with the passed parameter? Instantiating it in the XSLT is not going to work in my actual use case. Thanks.

You need to say what XSLT processor you are using. The JAXP API does not define any mechanism for calling from XSLT to Java, and conventions vary between different processors that implement the JAXP API. — Michael Kay
– Michael Kay, Commented Feb 17, 2017 at 23:25
@Michael Kay I'm using Java 8 and it seems to be picking up Xalan — J Dillon
– J Dillon, Commented Feb 17, 2017 at 23:27
Possible duplicate of Error when calling java static method from xslt — dube
– dube, Commented Jan 18, 2018 at 15:40

Juan Mellado · Accepted Answer · 2017-02-17 23:21:22Z

1

In order to get this line working:

<xsl:value-of select="test:get($test1)"/>

The parameter could be passed to a static function:

class Test {

  public static void get(Object context) {
     // here "context" is the instance "test1"
  }
...

answered Feb 17, 2017 at 23:21

Juan Mellado

15.2k5 gold badges50 silver badges54 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Grief Over a year ago

That is the only way I found to call instance methods in Xalan. Strange that it was not upvoted. Although it requires a wrapping to target java method with Object parameter, it works and the wrapping is not a big deal.

General Grievance · Accepted Answer · 2021-02-05 16:25:14Z

0

I also faced same issue. After checking found that we need to use below dependencies

        <dependency>
            <groupId>xalan</groupId>
            <artifactId>serializer</artifactId>
            <version>2.7.2</version>
        </dependency>
        
        
        <dependency>
            <groupId>xalan</groupId>
            <artifactId>xalan</artifactId>
            <version>2.7.2</version>
        </dependency>

After adding these dependencies my code get works.

edited Feb 5, 2021 at 16:25

General Grievance

5,12039 gold badges40 silver badges60 bronze badges

answered Feb 5, 2021 at 15:49

Kunal Lavand

11 bronze badge

Collectives™ on Stack Overflow

How can I call a method on a Java instance passed into XSLT?

2 Answers 2

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related