在jsf中保存对话框

Question

我使用IText库创建了pdf现在，我希望当用户单击按钮时，它应该向用户提示一个保存对话框，允许用户浏览存储文件的目标位置。

现在我的代码看起来像

    Document document = new Document();
    try {
                    FacesContext context = FacesContext.getCurrentInstance();
        HttpServletResponse response = (HttpServletResponse) context.getExternalContext().getResponse();
        response.reset();  
        response.setContentType("application/pdf");
        response.setHeader("Content-Disposition", "attachment; filename=ABC.pdf");
        response.setHeader("Cache-Control", "no-cache");  
        response.setDateHeader("Expires", 0);  
        response.setHeader("Pragma", "No-cache");
        PdfWriter.getInstance(document, response.getOutputStream());
        document.addTitle("Form");
        document.addSubject("Form");
        document.open();
        Paragraph paragraph12 = new Paragraph("FORM",
        FontFactory.getFont(FontFactory.HELVETICA,
        18, Font.BOLD, new CMYKColor(0, 255, 255, 17)));
        Chapter chapter1 = new Chapter(paragraph12, 1);
        paragraph12.setSpacingAfter(25);
        paragraph12.setAlignment(Element.ALIGN_CENTER);
        document.add(paragraph12);
        // Centered
        Chunk underline = new Chunk(AppNo);
        underline.setUnderline(0.2f, -2f);
        Paragraph paragraph = new Paragraph("Application No:");
        paragraph.add(underline);
        paragraph.setAlignment(Element.ALIGN_LEFT);
        paragraph.setSpacingAfter(20);
        document.add(paragraph);
        // Left
        paragraph = new Paragraph("To,");
        paragraph.setAlignment(Element.ALIGN_LEFT);
        document.add(paragraph);
        // Left with indentation
        paragraph = new Paragraph(
                "");
        paragraph.setAlignment(Element.ALIGN_LEFT);
        document.add(paragraph);
        Paragraph paragraph2 = new Paragraph(
                "Subject: ");
        paragraph2.setSpacingAfter(15);
        paragraph2.setSpacingBefore(15);
        paragraph2.setAlignment(Element.ALIGN_LEFT);
        paragraph2.setIndentationRight(50);
        document.add(paragraph2);

        Paragraph paragraph3 = new Paragraph("I  ");
        String laName=deaclarationOpr.getDeclarationDetailsobj()
                .getLaName();
        if(laName!=null){
        Chunk name = new Chunk(laName);
        name.setUnderline(0.2f, -2f);
        paragraph3.add(name);
        }
        paragraph3.add("  request you to process the Application  ");
        paragraph3.add(underline);
        paragraph3.add("  for product  ");

        String productName=deaclarationOpr
                .getDeclarationDetailsobj().getProductName();
        if(productName!=null){
        Chunk product = new Chunk(productName);
        product.setUnderline(0.2f, -2f);
        paragraph3.add(product);
        }
        paragraph3
                .add("");
        paragraph3.setSpacingAfter(15);
        paragraph3.setSpacingBefore(15);
        paragraph3.setAlignment(Element.ALIGN_LEFT);
        paragraph3.setIndentationLeft(50);
        paragraph3.setIndentationRight(50);
        document.add(paragraph3);
        Paragraph paragraph4 = new Paragraph(
                "");


        String code=deaclarationOpr
                .getDeclarationDetailsobj().getAdvisorCode();
        if(code!=null){
        Chunk advisorCode = new Chunk(code);
        advisorCode.setUnderline(0.2f, -2f);
        paragraph4.add(advisorCode);
        }
        paragraph4
                .add("");
        paragraph4.setSpacingAfter(15);
        paragraph4.setSpacingBefore(15);
        paragraph4.setAlignment(Element.ALIGN_LEFT);
        paragraph4.setIndentationLeft(50);
        paragraph4.setIndentationRight(50);
        document.add(paragraph4);
        Paragraph paragraph5 = new Paragraph(
                "");
        paragraph5.setSpacingAfter(15);
        paragraph5.setSpacingBefore(15);
        paragraph5.setAlignment(Element.ALIGN_LEFT);
        paragraph5.setIndentationLeft(50);
        paragraph3.setIndentationRight(50);
        document.add(paragraph5);
        Paragraph paragraph6 = new Paragraph(
                "");
        paragraph6.setSpacingAfter(15);
        paragraph6.setSpacingBefore(15);
        paragraph6.setAlignment(Element.ALIGN_LEFT);
        paragraph6.setIndentationLeft(50);
        paragraph6.setIndentationRight(50);
        document.add(paragraph6);
        Paragraph paragraph7 = new Paragraph("Date:      ");
        DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
        // get current date time with Date()
        Date date = new Date();
        paragraph7.add(dateFormat.format(date));
        paragraph7.setSpacingBefore(15);
        paragraph7.setIndentationLeft(50);
        paragraph7.setIndentationRight(50);
        paragraph7.setAlignment(Element.ALIGN_LEFT);
        document.add(paragraph7);
        Paragraph paragraph8 = new Paragraph("Name of the Proposer:      ");
        String propoer=deaclarationOpr
                .getDeclarationDetailsobj().getProposerName();
        if(propoer!=null){
        Chunk proposerName = new Chunk(propoer);
        proposerName.setUnderline(0.2f, -2f);
        paragraph8.add(proposerName);
        }
        paragraph8.setAlignment(Element.ALIGN_LEFT);
        paragraph8.setIndentationLeft(50);
        paragraph8.setIndentationRight(50);
        document.add(paragraph8);
        Paragraph paragraph9 = new Paragraph("Place:      ");
        paragraph9.setIndentationLeft(50);
        paragraph9.setIndentationRight(50);
        paragraph9.setAlignment(Element.ALIGN_LEFT);
        document.add(paragraph9);

        document.close();

context.responseComplete((；}catch(FileNotFoundException e({//TODO自动生成的catch块e.printStackTrace((；}catch(DocumentException e({//TODO自动生成的catch块e.printStackTrace((；}

以下过滤器在web.xml 中定义

<filter>
        <display-name>RichFaces Filter</display-name>
        <filter-name>richfaces</filter-name>
        <filter-class>org.ajax4jsf.Filter</filter-class>
        <init-param>
            <param-name>createTempFiles</param-name>
            <param-value>false</param-value>
        </init-param>
        <init-param>
            <param-name>maxRequestSize</param-name>
            <param-value>20000000</param-value>
        </init-param>
        <init-param>
            <param-name>enable-cache</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>richfaces</filter-name>
        <servlet-name>Faces Servlet</servlet-name>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>FORWARD</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
    </filter-mapping>

上面的代码是用BackingBean类的方法编写的

并调用

<tr>
<td align="center"><a4j:commandButton
value="Print" styleClass="button"
action="#{declarationBB.convertToPdf}"></a4j:commandButton></td>
</tr>

我在下面的新页面

%PDF-1.4 %��3 0 obj <>stream x��V����Ժ@��rs�0��m|셒F6[�T���H[��E D'��7�� 

Answer 1

只需将PDF写入HTTP响应，而不是本地文件。

更换

PdfWriter.getInstance(document, new FileOutputStream("D:/Files/ABC.pdf"));

通过

FacesContext context = FacesContext.getCurrentInstance();
HttpServletResponse response = (HttpServletResponse) context.getExternalContext().getResponse();
response.setContentType("application/pdf");
response.setHeader("Content-Disposition", "attachment; filename="ABC.pdf"");
PdfWriter.getInstance(document, response.getOutputStream());
// ... (your PDF building code here)
context.responseComplete();

并在与下载按钮相关联的动作方法中调用它。值为attachment的Content-Disposition标头将强制执行另存为对话框(除非浏览器配置为在Adobe Reader中自动打开PDF文件！(。

另请参阅：

• 如何提供从JSF支持bean下载的文件

---

更新：根据您的更新，您正在通过ajax调用下载。

<a4j:commandButton value="Print" styleClass="button" action="#{declarationBB.convertToPdf}"></a4j:commandButton>

这行不通。您无法通过ajax下载文件。Ajax是由JavaScript执行的，但由于明显的安全原因，它没有以编程方式强制另存为对话的设施，其中包含一些变量中异步获取/生成的内容。让它成为一个正常的请求。请改用<h:commandButton>。