Question

我正在使用ColdFusion和iText生成PDF文档，我希望能够在iText决定进行分页时“自动”向PDF添加页眉和页脚。我已经看到了如何在Java中执行此操作的示例，以下是执行此操作的基本方法：

public class MyHeaderFooterPageEvent extends PdfPageEventHelper {
    public void onEndPage(PdfWriter writer, Document document) {
        //add your content here
    }
}

然后，在开始撰写PDF文档之前，您将“注册”您的活动，如：

    MyHeaderFooterPageEvent event = new HeaderFooterPageEvent();
    writer.setPageEvent(event);

（至少据我所知。）

我已成功设法将类PdfPageEventHelper加载到ColdFusion中，所以我知道它在那里：

<cfset local.PdfPageEventHelper=CreateObject("java","com.lowagie.text.pdf.PdfPageEventHelper")>

当我转储local.PdfPageEventHelper时，我得到：

那么如何在调用onEndPage时告诉ColdFusion该怎么做，以及如何注册该事件以便调用它？

我在Linux服务器上使用Coldfusion 11。

Answer 1

此解决方案主要基于this old blog post at cfSearching.blogspot.se。

虽然该解决方案使用 javaloader动态代理库，但此解决方案使用较新的（？）函数CreateDynamicProxy（我认为可以从ColdFusion 10获得）， Ageax （非常感谢！）让我意识到了。

已在Linux服务器上的 ColdFusion 11 中成功测试。

自己尝试一下：

将以下内容复制并粘贴到一个cfm文件和一个cfc文件中。虽然您可以根据需要为cfm文件命名，但cfc文件必须命名为 PdfPageEventHandler.cfc 才能使此代码正常工作。

将文件放在ColdFusion服务器上的www根目录中的同一文件夹中。

通过浏览cfm文件运行代码。

浏览器应显示包含正文文本和页脚的3页PDF。

cfm文件的内容：

 <cfset _createPdf()>  <cffunction name="_createPdf" output="no" returntype="void"> <cfargument name="pdfFile" type="string" default="document.pdf" hint="the file name to write to disc"> <cfargument name="writeToBrowser" type="boolean" default="true" hint="will open the pdf document in the browser and delete the file when done"> <cfscript> //set filePath for document local.filePath = ExpandPath('.')&"/"&arguments.pdfFile; //get BaseFont local.BaseFont = CreateObject("java", "com.lowagie.text.pdf.BaseFont"); //get CMYK color local.CMYKColor = CreateObject("java", "com.lowagie.text.pdf.CMYKColor"); //create color local.color = local.CMYKColor.init(JavaCast("int",0),JavaCast("int",0),JavaCast("int",0),JavaCast("int",256)); //create font local.font = local.BaseFont.createFont(local.BaseFont.COURIER, local.BaseFont.CP1252, true); //compose custom config to make accessable in PdfPageEventHandler.cfc local.config = {myCustomFooter = {text = "Page number", color = local.color, font = local.font, size = 20}}; //init the event handler (make sure the PdfPageEventHandler.cfc is present in the same folder as this template) local.eventHandler = CreateObject("component", "PdfPageEventHandler").init(config = local.config); //we can pass in an array of strings which name all the interfaces we want out dynamic proxy to implement local.interfaces = ["com.lowagie.text.pdf.PdfPageEvent"]; //create a dynamic proxy that we will pass to the iText writer local.eventHandlerProxy = CreateDynamicProxy(local.eventHandler, local.interfaces); //init success flag local.success = true; try { //init document local.document = CreateObject("java", "com.lowagie.text.Document").init(); //init outstream local.outputStream = CreateObject("java", "java.io.FileOutputStream").init(local.filePath); //init writer local.writer = CreateObject("java", "com.lowagie.text.pdf.PdfWriter").getInstance(local.document, local.outputStream); //register the PROXY as the page event handler local.writer.setPageEvent(local.eventHandlerProxy); //open document local.document.open(); //init paragraph local.paragraph = CreateObject("java", "com.lowagie.text.Paragraph"); //output some pages with a simple text message. NOTE that our eventHandler will take care of adding footers on every page - that's the whole point with this example by the way :) for (local.i = 1; local.i lte 3; local.i = local.i + 1) { //add paragraph with text local.document.add(local.paragraph.init("This page should have a footer with a page number on it!")); //trigger new page local.document.newPage(); } } catch (any e) { //an error occured WriteOutput("Error: " & e.message); //set success flag to false local.success = false; } if (StructKeyExists(local, "document")) { //close document local.document.close(); } if (StructKeyExists(local, "outStream")) { //close outStream local.outputStream.close(); } if (local.success && arguments.writeToBrowser) { _openPdf(filePath=local.filePath); } </cfscript> </cffunction>  <cffunction name="_openPdf" output="no" returntype="void"> <cfargument name="filePath" type="string" required="yes"> <cfcontent type="application/pdf" file="#arguments.filePath#" deletefile="yes"> </cffunction>

cfc文件的内容，应命名为 PdfPageEventHandler.cfc ：

<cfcomponent output="false" hint="iText Event handler used to add headers, footers, etc.">  <cffunction name="init" access="public" returntype="PdfPageEventHandler" output="false">  <cfargument name="config" type="any" required="true" hint="custom config" />  <cfset variables.config = arguments.config> <cfreturn this /> </cffunction>  <cffunction name="onEndPage" access="public" returntype="void" output="true" hint="Called when a page is finished, just before being written to the document."> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" />  <cfscript> local.cb = arguments.writer.getDirectContent(); local.cb.saveState(); local.cb.beginText(); local.cb.setColorFill(variables.config.myCustomFooter.color); local.cb.setFontAndSize(variables.config.myCustomFooter.font, variables.config.myCustomFooter.size); local.cb.setTextMatrix(arguments.document.left(), arguments.document.bottom() - 10); local.text = "#variables.config.myCustomFooter.text# #arguments.writer.getPageNumber()#"; local.cb.showText(local.text); local.cb.endText(); local.cb.restoreState(); </cfscript> </cffunction>  <cffunction name="onOpenDocument" access="public" returntype="void" output="false" hint="Called when the document is opened."> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" />  </cffunction> <cffunction name="onCloseDocument" access="public" returntype="void" output="false" hint="Called when the document is closed"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" />  </cffunction> <cffunction name="onStartPage" access="public" returntype="void" output="false" hint="Called when a page is initialized."> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" />  </cffunction> <cffunction name="onParagraph" access="public" returntype="void" output="false" hint="Called when a Paragraph is written"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="paragraphPosition" type="numeric" required="true" hint="The position the chapter will be written to. Value is a java float" />  </cffunction> <cffunction name="onParagraphEnd" access="public" returntype="void" output="false" hint="Called when a Paragraph is written"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="paragraphPosition" type="numeric" required="true" hint="The position the chapter will be written to. Value is a java float" />  </cffunction>  </cffunction> <cffunction name="onChapterEnd" access="public" returntype="void" output="false" hint="Called when the end of a Chapter is reached"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="position" type="numeric" required="true" hint="The position of the end of the chapter. Value is a java float" />  </cffunction> <cffunction name="onGenericTag" access="public" returntype="void" output="false" hint="Called when a Chunk with a generic tag is written"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="rect" type="any" required="true" hint="The Rectangle containing the Chunk. Instance of com.lowagie.text.Rectangle" /> <cfargument name="text" type="string" required="true" hint="The text of the tag" />  </cffunction> <cffunction name="onSection" access="public" returntype="void" output="false" hint="Called when a Section is written"> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="paragraphPosition" type="numeric" required="true" hint="The position the chapter will be written to. Value is a java float" /> <cfargument name="depth" type="numeric" required="true" hint="The number depth of the Section. Value is a java int" /> <cfargument name="title" type="any" required="true" hint="Title of the section. Instance of com.lowagie.text.Paragraph" />  </cffunction> <cffunction name="onSectionEnd" access="public" returntype="void" output="false" hint="Called when the end of a Section is reached."> <cfargument name="writer" type="any" required="true" hint="Writer for the target pdf. Instance of com.lowagie.text.pdf.PdfWriter" /> <cfargument name="document" type="any" required="true" hint="Document for target pdf. Instance of com.lowagie.text.Document" /> <cfargument name="paragraphPosition" type="numeric" required="true" hint="The position the chapter will be written to. Value is a java float" /> <cfargument name="depth" type="numeric" required="true" hint="The number depth of the Section. Value is a java int" /> <cfargument name="title" type="numeric" required="true" hint="Title of the section. Instance of com.lowagie.text.Paragraph" />  </cffunction> ---> </cfcomponent>

<强>更新<！/强>

这里有相同的cfc，但在纯cfscript中，对你而言更喜欢：

<cfscript> component output="false" hint="iText Event handler used to add headers, footers, etc." { property name="config" type="struct"; //1. INIT FUNCTION public PdfPageEventHandler function init(required any config) { //make sure the config is accessable by other functions variables.config = arguments.config; return this; } //2. ON END PAGE - the function that is in focus in this example public void function onEndPage(required any writer, required any document) { //Called when a page is finished, just before being written to the document //edit below to make your own header / footer local.cb = arguments.writer.getDirectContent(); local.cb.saveState(); local.cb.beginText(); local.cb.setColorFill(variables.config.myCustomFooter.color); local.cb.setFontAndSize(variables.config.myCustomFooter.font, variables.config.myCustomFooter.size); local.cb.setTextMatrix(arguments.document.left(), arguments.document.bottom() - 10); local.text = "#variables.config.myCustomFooter.text# #arguments.writer.getPageNumber()#"; local.cb.showText(local.text); local.cb.endText(); local.cb.restoreState(); } //3. OTHER FUNCTIONS THAT MUST EXIST (at least in this example) public void function onOpenDocument(required any writer, required any document) { //Called when the document is opened } public void function onCloseDocument(required any writer, required any document) { //Called when the document is closed } public void function onStartPage(required any writer, required any document) { //Called when a page is initialized } public void function onParagraph(required any writer, required any document, required numeric paragraphPosition) { //Called when a Paragraph is written //paragraphPosition - The position the chapter will be written to. Value is a java float } public void function onParagraphEnd(required any writer, required any document, required numeric paragraphPosition) { //Called when a Paragraph is written //paragraphPosition - The position the chapter will be written to. Value is a java float } //4. FUNCTIONS THAT ONLY NEEDS TO EXIST IF YOU DO SOMETHING THAT TRIGGERS THEM public void function OnChapter(required any writer, required any document, required numeric paragraphPosition, required any title) { //Called when a Chapter is written //paragraphPosition - The position the chapter will be written to. Value is a java float //title - Title of the chapter. Instance of com.lowagie.text.Paragraph } public void function onChapterEnd(required any writer, required any document, required numeric position) { //Called when the end of a Chapter is reached //position - The position of the end of the chapter. Value is a java float } public void function onGenericTag(required any writer, required any document, required any rect, required string text) { //Called when a Chunk with a generic tag is written //rect - The Rectangle containing the Chunk. Instance of com.lowagie.text.Rectangle //text - The text of the tag } public void function onSection(required any writer, required any document, required numeric paragraphPosition, required numeric depth, required any title) { //Called when a Section is written //paragraphPosition - The position the section will be written to. Value is a java float //depth - The number depth of the Section. Value is a java int //title - Title of the section. Instance of com.lowagie.text.Paragraph } public void function onSectionEnd(required any writer, required any document, required numeric paragraphPosition, required numeric depth, required any title) { //Called when the end of a Section is reached //paragraphPosition - The position the section will be written to. Value is a java float //depth - The number depth of the Section. Value is a java int //title - Title of the section. Instance of com.lowagie.text.Paragraph } } </cfscript>

使用Coldfusion和iText通过onEndPage向PDF添加页脚/页眉

1 个答案: