org.springframework.web.servlet.view.document

Class AbstractPdfView

java.lang.Object

org.springframework.context.support.ApplicationObjectSupport

org.springframework.web.context.support.WebApplicationObjectSupport

org.springframework.web.servlet.view.AbstractView

org.springframework.web.servlet.view.document.AbstractPdfView

All Implemented Interfaces:

Aware, BeanNameAware, ApplicationContextAware, ServletContextAware, View

public abstract class AbstractPdfView
extends AbstractView

Abstract superclass for PDF views. Application-specific view classes will extend this class. The view will be held in the subclass itself, not in a template.

This view implementation uses Bruno Lowagie's iText API. Known to work with the original iText 2.1.7 as well as its fork OpenPDF. We strongly recommend OpenPDF since it is actively maintained and fixes an important vulnerability for untrusted PDF content.

Note: Internet Explorer requires a ".pdf" extension, as it doesn't always respect the declared content type.

Author:

Rod Johnson, Juergen Hoeller, Jean-Pierre Pawlak

See Also:

AbstractPdfStamperView

Field Summary

Fields inherited from class org.springframework.web.servlet.view.AbstractView

DEFAULT_CONTENT_TYPE

Fields inherited from class org.springframework.context.support.ApplicationObjectSupport

logger

Fields inherited from interface org.springframework.web.servlet.View

PATH_VARIABLES, RESPONSE_STATUS_ATTRIBUTE, SELECTED_CONTENT_TYPE

Constructor Summary

Constructors

Constructor and Description
AbstractPdfView() This constructor sets the appropriate content type "application/pdf".

Method Summary

Modifier and Type	Method and Description
protected abstract void	buildPdfDocument(Map<String,Object> model, com.lowagie.text.Document document, com.lowagie.text.pdf.PdfWriter writer, HttpServletRequest request, HttpServletResponse response) Subclasses must implement this method to build an iText PDF document, given the model.
protected void	buildPdfMetadata(Map<String,Object> model, com.lowagie.text.Document document, HttpServletRequest request) Populate the iText Document's meta fields (author, title, etc.).
protected boolean	generatesDownloadContent() Return whether this view generates download content (typically binary content like PDF or Excel files).
protected int	getViewerPreferences() Return the viewer preferences for the PDF file.
protected com.lowagie.text.Document	newDocument() Create a new document to hold the PDF contents.
protected com.lowagie.text.pdf.PdfWriter	newWriter(com.lowagie.text.Document document, OutputStream os) Create a new PdfWriter for the given iText Document.
protected void	prepareWriter(Map<String,Object> model, com.lowagie.text.pdf.PdfWriter writer, HttpServletRequest request) Prepare the given PdfWriter.
protected void	renderMergedOutputModel(Map<String,Object> model, HttpServletRequest request, HttpServletResponse response) Subclasses must implement this method to actually render the view.

Methods inherited from class org.springframework.web.servlet.view.AbstractView

addStaticAttribute, createMergedOutputModel, createRequestContext, createTemporaryOutputStream, exposeModelAsRequestAttributes, formatViewName, getAttributesMap, getBeanName, getContentType, getRequestContextAttribute, getRequestToExpose, getStaticAttributes, isExposePathVariables, prepareResponse, render, setAttributes, setAttributesCSV, setAttributesMap, setBeanName, setContentType, setExposeContextBeansAsAttributes, setExposedContextBeanNames, setExposePathVariables, setRequestContextAttribute, setResponseContentType, toString, writeToResponse

Methods inherited from class org.springframework.web.context.support.WebApplicationObjectSupport

getServletContext, getTempDir, getWebApplicationContext, initApplicationContext, initServletContext, isContextRequired, setServletContext

Methods inherited from class org.springframework.context.support.ApplicationObjectSupport

getApplicationContext, getMessageSourceAccessor, initApplicationContext, obtainApplicationContext, requiredContextClass, setApplicationContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AbstractPdfView

public AbstractPdfView()

This constructor sets the appropriate content type "application/pdf". Note that IE won't take much notice of this, but there's not a lot we can do about this. Generated documents should have a ".pdf" extension.

Method Detail

generatesDownloadContent

protected boolean generatesDownloadContent()

Description copied from class: AbstractView

Return whether this view generates download content (typically binary content like PDF or Excel files).

The default implementation returns false. Subclasses are encouraged to return true here if they know that they are generating download content that requires temporary caching on the client side, typically via the response OutputStream.

Overrides:

generatesDownloadContent in class AbstractView

See Also:

AbstractView.prepareResponse(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse), ServletResponse.getOutputStream()

renderMergedOutputModel

protected final void renderMergedOutputModel(Map<String,Object> model,
                                             HttpServletRequest request,
                                             HttpServletResponse response)
                                      throws Exception

Description copied from class: AbstractView

Subclasses must implement this method to actually render the view.

The first step will be preparing the request: In the JSP case, this would mean setting model objects as request attributes. The second step will be the actual rendering of the view, for example including the JSP via a RequestDispatcher.

Specified by:

renderMergedOutputModel in class AbstractView

Parameters:

model - combined output Map (never null), with dynamic values taking precedence over static attributes

request - current HTTP request

response - current HTTP response

Throws:

Exception - if rendering failed

newDocument

protected com.lowagie.text.Document newDocument()

Create a new document to hold the PDF contents.

By default returns an A4 document, but the subclass can specify any Document, possibly parameterized via bean properties defined on the View.

Returns:

the newly created iText Document instance

See Also:

Document.Document(com.lowagie.text.Rectangle)

newWriter

protected com.lowagie.text.pdf.PdfWriter newWriter(com.lowagie.text.Document document,
                                                   OutputStream os)
                                            throws com.lowagie.text.DocumentException

Create a new PdfWriter for the given iText Document.

Parameters:

document - the iText Document to create a writer for

os - the OutputStream to write to

Returns:

the PdfWriter instance to use

Throws:

com.lowagie.text.DocumentException - if thrown during writer creation

prepareWriter

protected void prepareWriter(Map<String,Object> model,
                             com.lowagie.text.pdf.PdfWriter writer,
                             HttpServletRequest request)
                      throws com.lowagie.text.DocumentException

Prepare the given PdfWriter. Called before building the PDF document, that is, before the call to Document.open().

Useful for registering a page event listener, for example. The default implementation sets the viewer preferences as returned by this class's getViewerPreferences() method.

Parameters:

model - the model, in case meta information must be populated from it

writer - the PdfWriter to prepare

request - in case we need locale etc. Shouldn't look at attributes.

Throws:

com.lowagie.text.DocumentException - if thrown during writer preparation

See Also:

Document.open(), PdfWriter.setPageEvent(com.lowagie.text.pdf.PdfPageEvent), PdfWriter.setViewerPreferences(int), getViewerPreferences()

getViewerPreferences

protected int getViewerPreferences()

Return the viewer preferences for the PDF file.

By default returns AllowPrinting and PageLayoutSinglePage, but can be subclassed. The subclass can either have fixed preferences or retrieve them from bean properties defined on the View.

Returns:

an int containing the bits information against PdfWriter definitions

See Also:

PdfWriter.AllowPrinting, PdfWriter.PageLayoutSinglePage

buildPdfMetadata

protected void buildPdfMetadata(Map<String,Object> model,
                                com.lowagie.text.Document document,
                                HttpServletRequest request)

Populate the iText Document's meta fields (author, title, etc.).
Default is an empty implementation. Subclasses may override this method to add meta fields such as title, subject, author, creator, keywords, etc. This method is called after assigning a PdfWriter to the Document and before calling document.open().

Parameters:

model - the model, in case meta information must be populated from it

document - the iText document being populated

request - in case we need locale etc. Shouldn't look at attributes.

See Also:

Document.addTitle(java.lang.String), Document.addSubject(java.lang.String), Document.addKeywords(java.lang.String), Document.addAuthor(java.lang.String), Document.addCreator(java.lang.String), Document.addProducer(), Document.addCreationDate(), Document.addHeader(java.lang.String, java.lang.String)

buildPdfDocument

protected abstract void buildPdfDocument(Map<String,Object> model,
                                         com.lowagie.text.Document document,
                                         com.lowagie.text.pdf.PdfWriter writer,
                                         HttpServletRequest request,
                                         HttpServletResponse response)
                                  throws Exception

Subclasses must implement this method to build an iText PDF document, given the model. Called between Document.open() and Document.close() calls.

Note that the passed-in HTTP response is just supposed to be used for setting cookies or other HTTP headers. The built PDF document itself will automatically get written to the response after this method returns.

Parameters:

model - the model Map

document - the iText Document to add elements to

writer - the PdfWriter to use

request - in case we need locale etc. Shouldn't look at attributes.

response - in case we need to set cookies. Shouldn't write to it.

Throws:

Exception - any exception that occurred during document building

See Also:

Document.open(), Document.close()