Hi,
I have been using FOP to create PDF files for sometime now. Mostly as
embedded code within my Struts Action classes, as mentioned in
http://xml.apache.org/fop/embedding.html and it has been working just fine.
But this method requires the xml source to exist only as a java.io.File (if
I am not mistaken), with no provision as an in memory object - like a Java
String or Stream for example.
So when I looked at the Xalan site and this mailing list I saw the in
memory implementation possible with the TransformerFactory and Transformer
classes in Xalan. So, I tried this with a simple xml and xsl to test the
concept first. But, I seem to be getting the error
building formatting object tree
building formatting object tree
javax.xml.transform.TransformerException
at
org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerIm
pl.java:1212)
at
org.apache.xalan.transformer.TransformerImpl.run(TransformerImpl.java:2894)
at java.lang.Thread.run(Thread.java:484)
---------
java.lang.NullPointerException
at
org.apache.fop.fo.FOTreeBuilder.startDocument(FOTreeBuilder.java:167)
at
org.apache.xalan.transformer.QueuedStartDocument.flush(QueuedStartDocume
nt.java:108)
at
org.apache.xalan.transformer.ResultTreeHandler.flushPending(ResultTreeHa
ndler.java:758)
at
org.apache.xalan.transformer.ResultTreeHandler.startElement(ResultTreeHa
ndler.java:245)
at
org.apache.xalan.transformer.ResultTreeHandler.startElement(ResultTreeHa
ndler.java:209)
at
org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.j
ava:704)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(Trans
formerImpl.java:2154)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(Trans
formerImpl.java:2097)
at
org.apache.xalan.transformer.TransformerImpl.applyTemplateToNode(Transfo
rmerImpl.java:2029)
at
org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerIm
pl.java:1189)
at
org.apache.xalan.transformer.TransformerImpl.run(TransformerImpl.java:2894)
at java.lang.Thread.run(Thread.java:484)
javax.xml.transform.TransformerException
at
org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerIm
pl.java:1212)
at
org.apache.xalan.transformer.TransformerImpl.run(TransformerImpl.java:2894)
at java.lang.Thread.run(Thread.java:484)
---------
java.lang.NullPointerException
at
org.apache.fop.fo.FOTreeBuilder.startDocument(FOTreeBuilder.java:167)
at
org.apache.xalan.transformer.QueuedStartDocument.flush(QueuedStartDocume
nt.java:108)
at
org.apache.xalan.transformer.ResultTreeHandler.flushPending(ResultTreeHa
ndler.java:758)
at
org.apache.xalan.transformer.ResultTreeHandler.startElement(ResultTreeHa
ndler.java:245)
at org.apache.xalan.transformer.ResultTreeHandler.startElement(R
esultTreeHandler.java:209)
at
org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.j
ava:704)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(Trans
formerImpl.java:2154)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(Trans
formerImpl.java:2097)
at
org.apache.xalan.transformer.TransformerImpl.applyTemplateToNode(Transfo
rmerImpl.java:2029)
at
org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerIm
pl.java:1189)
at
org.apache.xalan.transformer.TransformerImpl.run(TransformerImpl.java:2894)
at java.lang.Thread.run(Thread.java:484)
I am using Fop-0.20.1 and the jars when compiling and running as below (on
a win2000 platform)
C:\Fop-0.20.1>javac -classpath
C:\Fop-0.20.1\lib\xalan-2.0.0.jar;C:\Fop-0.20.1\build\fop.jar TestXml.java
C:\Fop-0.20.1>java -classpath .;C:\Fop-0.20.1\lib\xalan-2.0.0.jar;C:\Fop
-0.20.1\build\fop.jar;C:\Fop-0.20.1\lib\batik.jar;C:\Fop-0.20.1\lib\xerc
es-1.2.3.jar TestXml
I have the bare minimum jar reqd for this test.
The xml and xsl are very simple and when used with FOP from the command
line gives a PDF output with no problems. But the above error is thrown
when used with the Java class TestXml
I was wondering if someone could help.
With the risk of making this mail even longer I will PASTE the Java code,
XML and XSL as is in the mail so as to avoid attachments. So I apologize
for the extremely long email :-)
JAVA code
----------------
import java.io.*;
import javax.xml.transform.*;
import javax.xml.transform.stream.*;
import javax.xml.transform.sax.*;
import org.apache.fop.apps.Driver;
public class TestXml {
public static void main(String[] args) {
try {
// XML Will eventually be a Java String or Stream from another
source.
StreamSource xmlsource = new StreamSource(new
FileReader("simple.xml"));
Driver driver =new Driver();
FileOutputStream fos = new FileOutputStream("simple.pdf");
driver.setOutputStream(fos);
driver.setRenderer(Driver.RENDER_TXT);
Transformer transformer =
TransformerFactory.newInstance().newTransformer(new StreamSource(new
FileReader("simple.xsl")));
// Does not work
transformer.transform(xmlsource, new
SAXResult(driver.getContentHandler()));
//Works
//transformer.transform(xmlsource, new
StreamResult(System.out));
} catch (Exception e) {
e.printStackTrace();
}
}
}
XML
--------
<?xml version="1.0"?>
<source>
<books>
<book year="2002">
<name>XML Bible</name>
<author>Elliot Rusty</author>
<desc>A great book for XML beginners.</desc>
</book>
<book year="2002">
<name>Thinking in Java</name>
<author>Bruce Eckel</author>
<desc>A great book for Java beginners.</desc>
</book>
</books>
</source>
XSL
----
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
xmlns:fo="http://www.w3.org/1999/XSL/Format";>
<xsl:template match="/">
<fo:root>
<fo:layout-master-set>
<fo:simple-page-master master-name="book-page"
page-height="11in"
page-width="8in" margin-top=".3in" margin-bottom=".5in" margin-left=".4in"
margin-right=".2in">
<fo:region-body margin-top="5.0in"
margin-bottom=".5in"/>
<fo:region-before extent="6in"/>
<fo:region-after extent=".5in"/>
</fo:simple-page-master>
</fo:layout-master-set>
<xsl:apply-templates/>
</fo:root>
</xsl:template>
<xsl:template match="source">
<fo:page-sequence master-name="book-page">
<fo:static-content flow-name="xsl-region-before">
<fo:block>
Various sources for XML/Java
</fo:block>
</fo:static-content>
<fo:flow flow-name="xsl-region-body">
<fo:block font-size="7pt"
text-indent=".5in">
<xsl:apply-templates/>
</fo:block>
</fo:flow>
</fo:page-sequence>
</xsl:template>
<xsl:template match="books">
<fo:block color="blue">
Books - <xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="book">
<fo:block color="green">
<xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="name">
<fo:block color="red">
<xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="author">
<fo:block color="orange">
<xsl:apply-templates/>
</fo:block>
</xsl:template>
<xsl:template match="desc">
<fo:block>
<xsl:apply-templates/>
</fo:block>
</xsl:template>
</xsl:stylesheet>
Thanks for the patience in reading this mail. Any help whatsoever will be
highly appreciated.
Thanks,
Anil.
