How do you create a PDF from XML in Java?
At the moment, I'm creating an XML file in Java and displaying it in a JSP page by transforming it with XSL/XSLT. Now I need to take that XML file and display the same information in a PDF. Is there a way I can do this by using some kind of XSL file?
I've seen the iText Java-PDF library, but I can't find any way to use it with XML and a stylesheet.
Any assistance would be much appreciated. Thanks in advance!
Answer
A - Explanation
You should use Apache FOP framework to generate pdf output. Simply you provide data in xml format and render the page with an xsl-fo file and specify the parameters like margin, page layout in this xsl-fo file.
I'll provide a simple demo, I use maven build tool to gather the needed jar files. Please notify that at the end of the page, there is an svg graphics embedded in pdf. I also want to demonstrate that you can embed svg graphics inside pdf.
B - Sample XML input data
<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="application/xml"?>
<users-data>
<header-section>
<data-type id="019">User Bill Data</data-type>
<process-date>Thursday December 9 2016 00:04:29</process-date>
</header-section>
<user-bill-data>
<full-name>John Doe</full-name>
<postal-code>34239</postal-code>
<national-id>123AD329248</national-id>
<price>17.84</price>
</user-bill-data>
<user-bill-data>
<full-name>Michael Doe</full-name>
<postal-code>54823</postal-code>
<national-id>942KFDSCW322</national-id>
<price>34.50</price>
</user-bill-data>
<user-bill-data>
<full-name>Jane Brown</full-name>
<postal-code>66742</postal-code>
<national-id>ABDD324KKD8</national-id>
<price>69.36</price>
</user-bill-data>
</users-data>
C - The XSL-FO Template
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format" version="1.0">
<xsl:output encoding="UTF-8" indent="yes" method="xml" standalone="no" omit-xml-declaration="no"/>
<xsl:template match="users-data">
<fo:root language="EN">
<fo:layout-master-set>
<fo:simple-page-master master-name="A4-portrail" page-height="297mm" page-width="210mm" margin-top="5mm" margin-bottom="5mm" margin-left="5mm" margin-right="5mm">
<fo:region-body margin-top="25mm" margin-bottom="20mm"/>
<fo:region-before region-name="xsl-region-before" extent="25mm" display-align="before" precedence="true"/>
</fo:simple-page-master>
</fo:layout-master-set>
<fo:page-sequence master-reference="A4-portrail">
<fo:static-content flow-name="xsl-region-before">
<fo:table table-layout="fixed" width="100%" font-size="10pt" border-color="black" border-width="0.4mm" border-style="solid">
<fo:table-column column-width="proportional-column-width(20)"/>
<fo:table-column column-width="proportional-column-width(45)"/>
<fo:table-column column-width="proportional-column-width(20)"/>
<fo:table-body>
<fo:table-row>
<fo:table-cell text-align="left" display-align="center" padding-left="2mm">
<fo:block>
Bill Id:<xsl:value-of select="header-section/data-type/@id"/>
, Date: <xsl:value-of select="header-section/process-date"/>
</fo:block>
</fo:table-cell>
<fo:table-cell text-align="center" display-align="center">
<fo:block font-size="150%">
<fo:basic-link external-destination="http://www.example.com">XXX COMPANY</fo:basic-link>
</fo:block>
<fo:block space-before="3mm"/>
</fo:table-cell>
<fo:table-cell text-align="right" display-align="center" padding-right="2mm">
<fo:block>
<xsl:value-of select="data-type"/>
</fo:block>
<fo:block display-align="before" space-before="6mm">Page <fo:page-number/> of <fo:page-number-citation ref-id="end-of-document"/>
</fo:block>
</fo:table-cell>
</fo:table-row>
</fo:table-body>
</fo:table>
</fo:static-content>
<fo:flow flow-name="xsl-region-body" border-collapse="collapse" reference-orientation="0">
<fo:block>MONTHLY BILL REPORT</fo:block>
<fo:table table-layout="fixed" width="100%" font-size="10pt" border-color="black" border-width="0.35mm" border-style="solid" text-align="center" display-align="center" space-after="5mm">
<fo:table-column column-width="proportional-column-width(20)"/>
<fo:table-column column-width="proportional-column-width(30)"/>
<fo:table-column column-width="proportional-column-width(25)"/>
<fo:table-column column-width="proportional-column-width(50)"/>
<fo:table-body font-size="95%">
<fo:table-row height="8mm">
<fo:table-cell>
<fo:block>Full Name</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>Postal Code</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>National ID</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>Payment</fo:block>
</fo:table-cell>
</fo:table-row>
<xsl:for-each select="user-bill-data">
<fo:table-row>
<fo:table-cell>
<fo:block>
<xsl:value-of select="full-name"/>
</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>
<xsl:value-of select="postal-code"/>
</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>
<xsl:value-of select="national-id"/>
</fo:block>
</fo:table-cell>
<fo:table-cell>
<fo:block>
<xsl:value-of select="price"/>
</fo:block>
</fo:table-cell>
</fo:table-row>
</xsl:for-each>
</fo:table-body>
</fo:table>
<fo:block id="end-of-document">
<fo:instream-foreign-object>
<svg width="200mm" height="150mm" version="1.1" xmlns="http://www.w3.org/2000/svg">
<path d="M153 334
C153 334 151 334 151 334
C151 339 153 344 156 344
C164 344 171 339 171 334
C171 322 164 314 156 314
C142 314 131 322 131 334
C131 350 142 364 156 364
C175 364 191 350 191 334
C191 311 175 294 156 294
C131 294 111 311 111 334
C111 361 131 384 156 384
C186 384 211 361 211 334
C211 300 186 274 156 274" style="fill:yellow;stroke:red;stroke-width:2"/>
</svg>
</fo:instream-foreign-object>
</fo:block>
</fo:flow>
</fo:page-sequence>
</fo:root>
</xsl:template>
</xsl:stylesheet>
D - Project Directory Structure
E - Pom file
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.levent.fopdemo</groupId>
<artifactId>apache-fop-demo</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>apache-fop-demo</name>
<url>http://maven.apache.org</url>
<properties>
<fop.version>2.1</fop.version>
</properties>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.apache.xmlgraphics/fop -->
<dependency>
<groupId>org.apache.xmlgraphics</groupId>
<artifactId>fop</artifactId>
<version>${fop.version}</version>
</dependency>
</dependencies>
<build>
<finalName>Apache Fop Demo</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
F - Demo Code: PdfGenerationDemo.java
package com.levent.fopdemo;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import javax.xml.transform.Result;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.stream.StreamSource;
import org.apache.fop.apps.FOPException;
import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.apps.Fop;
import org.apache.fop.apps.FopFactory;
import org.apache.fop.apps.MimeConstants;
public class PdfGenerationDemo
{
public static final String RESOURCES_DIR;
public static final String OUTPUT_DIR;
static {
RESOURCES_DIR = "src//main//resources//";
OUTPUT_DIR = "src//main//resources//output//";
}
public static void main( String[] args )
{
try {
convertToPDF();
} catch (FOPException | IOException | TransformerException e) {
e.printStackTrace();
}
}
public static void convertToPDF() throws IOException, FOPException, TransformerException {
// the XSL FO file
File xsltFile = new File(RESOURCES_DIR + "//template.xsl");
// the XML file which provides the input
StreamSource xmlSource = new StreamSource(new File(RESOURCES_DIR + "//data.xml"));
// create an instance of fop factory
FopFactory fopFactory = FopFactory.newInstance(new File(".").toURI());
// a user agent is needed for transformation
FOUserAgent foUserAgent = fopFactory.newFOUserAgent();
// Setup output
OutputStream out;
out = new java.io.FileOutputStream(OUTPUT_DIR + "//output.pdf");
try {
// Construct fop with desired output format
Fop fop = fopFactory.newFop(MimeConstants.MIME_PDF, foUserAgent, out);
// Setup XSLT
TransformerFactory factory = TransformerFactory.newInstance();
Transformer transformer = factory.newTransformer(new StreamSource(xsltFile));
// Resulting SAX events (the generated FO) must be piped through to
// FOP
Result res = new SAXResult(fop.getDefaultHandler());
// Start XSLT transformation and FOP processing
// That's where the XML is first transformed to XSL-FO and then
// PDF is created
transformer.transform(xmlSource, res);
} finally {
out.close();
}
}
}
G - Sample Output: output.pdf
