Java Xml to Pdf Fop Example
What is Apache FOP
Apache™ FOP (Formatting Objects Processor) is a print formatter driven by XSL formatting objects (XSL-FO) and an output independent formatter. It is a Java application that reads a formatting object (FO) tree and renders the resulting pages to a specified output.
FOP uses the standard XSL-FO file format as input, lays the content out into pages, then renders it to the requested output.
Read more about it here – https://xmlgraphics.apache.org/fop/
Steps for creating a PDF from XML
To produce a PDF file from a XML file, first step is that we need an XSLT stylesheet that converts the XML to XSL-FO. Created XSL-FO file is also an XML file which contains formatted objects.
The second step will be done by FOP when it reads the generated XSL-FO document and formats it to a PDF document.
How to get Apache FOP
Get the FOP download from here.
https://xmlgraphics.apache.org/fop/download.html
I have used fop-2.0 for this example code.
Needed jars (found in the lib and build directory in the fop download) –
- Commons-io
- Commons-logging
- Xml-apis
- Xmlgraphics-commons
- Fop
- Batik-all
- Avalon-framework
Example code
XML I used for creating PDF
<? xml version = "1.0" ?> <employees> <companyname> ABC Inc. </companyname> <employee> <id> 101 </id> <name> Ram </name> <designation> Manager </designation> </employee> <employee> <id> 102 </id> <name> Prabhu </name> <designation> Executive </designation> </employee> <employee> <id> 103 </id> <name> John </name> <designation> Executive </designation> </employee> </employees>
XSLUsed
<? xml version = "1.0" encoding = "UTF-8" ?> <xsl:stylesheet version = "1.1" xmlns:xsl = "http://www.w3.org/1999/XSL/Transform" xmlns:fo = "http://www.w3.org/1999/XSL/Format" exclude-result-prefixes = "fo" > <xsl:template match = "employees" > <fo:root xmlns:fo = "http://www.w3.org/1999/XSL/Format" > <fo:layout-master-set> <fo:simple-page-master master-name = "simpleA4" page-height = "29.7cm" page-width = "21cm" margin-top = "2cm" margin-bottom = "2cm" margin-left = "2cm" margin-right = "2cm" > <fo:region-body/> </fo:simple-page-master> </fo:layout-master-set> <fo:page-sequence master-reference = "simpleA4" > <fo:flow flow-name = "xsl-region-body" > <fo:block font-size = "16pt" font-weight = "bold" space-after = "5mm" > Company Name: <xsl:value-of select = "companyname" /> </fo:block> <fo:block font-size = "10pt" > <fo:table table-layout = "fixed" width = "100%" border-collapse = "separate" > <fo:table-column column-width = "4cm" /> <fo:table-column column-width = "4cm" /> <fo:table-column column-width = "5cm" /> <fo:table-body> <xsl:apply-templates select = "employee" /> </fo:table-body> </fo:table> </fo:block> </fo:flow> </fo:page-sequence> </fo:root> </xsl:template> <xsl:template match = "employee" > <fo:table-row> <xsl:if test = "designation = 'Manager'" > <xsl:attribute name = "font-weight" > bold </xsl:attribute> </xsl:if> <fo:table-cell> <fo:block> <xsl:value-of select = "id" /> </fo:block> </fo:table-cell> <fo:table-cell> <fo:block> <xsl:value-of select = "name" /> </fo:block> </fo:table-cell> <fo:table-cell> <fo:block> <xsl:value-of select = "designation" /> </fo:block> </fo:table-cell> </fo:table-row> </xsl:template> </xsl:stylesheet>
If you see the XSL, first I am looking for the employees element to get the company Name and also there some formatting is done like how many columns are needed and what should be the width. Then I am looking for the employee element and printing the values, also some logic is there to print the field values in bold if the designation is manager.
Copying the output of PDF I got, that will make it easy to understand the XSL.
Java code
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 . StreamResult ; 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 FOPPdfDemo { public static void main ( String [] args ) { FOPPdfDemo fOPPdfDemo = new FOPPdfDemo (); try { fOPPdfDemo . convertToPDF (); } catch ( FOPException e ) { // TODO Auto-generated catch block e . printStackTrace (); } catch ( IOException e ) { // TODO Auto-generated catch block e . printStackTrace (); } catch ( TransformerException e ) { // TODO Auto-generated catch block e . printStackTrace (); } } /** * Method that will convert the given XML to PDF * @throws IOException * @throws FOPException * @throws TransformerException */ public void convertToPDF () throws IOException , FOPException , TransformerException { // the XSL FO file File xsltFile = new File ( "F:\\Temp\\template.xsl" ); // the XML file which provides the input StreamSource xmlSource = new StreamSource ( new File ( "F:\\Temp\\Employees.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 ( "F:\\Temp\\employee.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 (); } } /** * This method will convert the given XML to XSL-FO * @throws IOException * @throws FOPException * @throws TransformerException */ public void convertToFO () throws IOException , FOPException , TransformerException { // the XSL FO file File xsltFile = new File ( "F:\\Temp\\template.xsl" ); /*TransformerFactory factory = TransformerFactory.newInstance(); Transformer transformer = factory.newTransformer(new StreamSource("F:\\Temp\\template.xsl"));*/ // the XML file which provides the input StreamSource xmlSource = new StreamSource ( new File ( "F:\\Temp\\Employees.xml" )); // a user agent is needed for transformation /*FOUserAgent foUserAgent = fopFactory.newFOUserAgent();*/ // Setup output OutputStream out ; out = new java . io . FileOutputStream ( "F:\\Temp\\temp.fo" ); try { // 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()); Result res = new StreamResult ( out ); //Start XSLT transformation and FOP processing transformer . transform ( xmlSource , res ); // 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 (); } } }
In the code there are two methods convertToPDF() and convertToFO(), convertToPDF() method is used to convert XML to PDF. convertToFO() method will create the XSL-FO from the XML using the XSLT. If you want to see the created FO which in turn is used to create PDF please call this method.
In case of web application if you want to provide PDF as a download add following lines with in the convertToPDF() method-
//Prepare response response . setContentType ( "application/pdf" ); response . setContentLength ( out . size ()); //Send content to Browser response . getOutputStream (). write ( out . toByteArray ()); response . getOutputStream (). flush ();
Reference : click here to go
My Notes:
How it works
We have an XML that holds data and an XSLT that creates an XML containing formatting objects by taking data from the first XML. This resultant XML is de-serialized into Java objects. FOP creates a PDF file using these Java objects.
Apache FOP Stuff
For space
<fo:leader leader-pattern="space"/>
For Horizontal Line
<fo:leader leader-pattern="rule" leader-length="100%" rule-style="solid" rule-thickness="0.5pt" color="#005598″/>
For Image display
<fo:external-graphic src=url('http://…………./tick.png') content-height="5%" content-width="5%"/>
or
<fo:external-graphic src='http://…………./tick.png' content-height="5%" content-width="5%"/>
How to use list elements(with Bullet character)
<fo:list-block > <!– list start –>
<fo:list-item> <!– list item –>
<fo:list-item-label end-indent="label-end()">
<fo:block>
<fo:inline font-family="Symbol">•</fo:inline> <!– insert a bullet –>
</fo:block>
</fo:list-item-label>
<fo:list-item-body start-indent="body-start()"><!– list text –>
<fo:block>
here is text in the list item body
</fo:block>
</fo:list-item-body>
</fo:list-item>
[other list items…]
</fo:list-block> <!– end list –>
fo:table-cell span 2 columns
<fo:table-cell number-columns-spanned="2">
XSLT Stuff
if else condition in XSLT
<xsl:choose>
<xsl:when test="expression">
… some output …
</xsl:when>
<xsl:otherwise>
… some output ….
</xsl:otherwise>
</xsl:choose>
check node value and display
<xsl:if test="nodeName[text() != " ]" </xsl:if> (node value is not empty then it will display else ignore
for-each in XSLT
<xsl:for-each select = ownerList/owner">
<xsl:value-of select="name"/>
<xs:value-of select="age"/>
</xsl:for-each>
List size check
<xsl:if test="count(ownerList/owner) > 0″>
</xsl:if>
Resources : https://www.ibm.com/developerworks/xml/library/x-xslfo2app/
Source: https://helpezee.wordpress.com/2017/02/26/creating-pdf-from-xml-using-apache-fop/
0 Response to "Java Xml to Pdf Fop Example"
Enregistrer un commentaire