Question

我收到堆空间错误/内存不足异常。我正在尝试使用iText生成PDF并使用aspose api将PDF转换为jpg图像。正在生成的PDF是3页，我正在逐页将PDF转换为图像并将它们拼接成一个jpg图像。这段代码在我的本地开发机器上工作正常，但在移动到测试服务器时会出现异常。

我正在使用的代码是：

public void silSignedPDF(AgreementBean agBean,String sourceTemplatePDFURL, Hashtable<String, String> val, String destinationPDFPath) throws IOException, DocumentException, SQLException{
 String methodName = "silSignedPDF";
LogTracer.writeDebugLog(className, methodName, "Start");
String serverPath = System.getProperty("jboss.server.home.dir");
String sourceTemplatePDFURL1 = serverPath+AppConstants.PDL_Agreement_Template +"/Online_Installment_Agreement.pdf";
System.out.println("sourceTemplatePDFURL1 "+sourceTemplatePDFURL1);

File f = new File(sourceTemplatePDFURL1);
InputStream sourceTemplatePDFUrlStream = new BufferedInputStream(new FileInputStream(f));
File destinationFile = new File(destinationPDFPath+"/"+agBean.getDealNbr()+".pdf");
PdfReader reader = new PdfReader(sourceTemplatePDFUrlStream);
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(
        destinationFile));
AcroFields form = stamper.getAcroFields();

Enumeration enumeration = val.keys();
// iterate through Hashtable val keys Enumeration
while (enumeration.hasMoreElements()) {
    String nextElement = (String) enumeration.nextElement();
    String nextElementValue = (String) val.get(nextElement);
    form.setField(nextElement, nextElementValue);
}
stamper.setFormFlattening(true);
stamper.close();

PdfConverter pdf = new PdfConverter();
pdf.bindPdf(destinationPDFPath+"/"+agBean.getDealNbr()+".pdf");
try {
    pdf.doConvert();
} catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

//set start and end pages
pdf.setStartPage(1);
pdf.setEndPage(1);

//initialize conversion process

//convert pages to images
String suffix = ".jpg";
int imageCount = 1;
while (pdf.hasNextImage())
{
    try {
        pdf.getNextImage(destinationPDFPath+"/"+agBean.getDealNbr()+"_"+imageCount + suffix,ImageType.JPEG);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
   imageCount++;
}
/* PDFImages pdfDoc = new PDFImages (destinationPDFPath+"/"+agBean.getDealNbr()+".pdf", null);
for (int count = 0; count < pdfDoc.getPageCount(); ++count)
{
    pdfDoc.savePageAsJPEG(count,destinationPDFPath+"/"+agBean.getDealNbr()+"_"+count + ".png", 150, 0.8f);
}*/
File file1 = new File(destinationPDFPath+"/"+agBean.getDealNbr()+"_1" + ".jpg");
File file2 = new File(destinationPDFPath+"/"+agBean.getDealNbr()+"_2" + ".jpg");
File file3 = new File(destinationPDFPath+"/"+agBean.getDealNbr()+"_3" + ".jpg");

BufferedImage img1 = ImageIO.read(file1);
BufferedImage img2 = ImageIO.read(file2);
BufferedImage img3 = ImageIO.read(file3);

int widthImg1 = img1.getWidth();
int heightImg1 = img1.getHeight();
int heightImg2 = img2.getHeight();
int heightImg3 = img3.getHeight();

BufferedImage img = new BufferedImage(
widthImg1, 
heightImg1+heightImg2+heightImg3, 
BufferedImage.TYPE_INT_RGB);

img.createGraphics().drawImage(img1, 0, 0, null); 
img.createGraphics().drawImage(img2, 0, heightImg1, null);
img.createGraphics().drawImage(img3, 0, heightImg1+heightImg2, null);

File final_image = new File(destinationPDFPath+"/"+agBean.getDealNbr() + ".jpg");
ImageIO.write(img, "png", final_image);
file1.delete();
file2.delete();
file3.delete();
LogTracer.writeDebugLog(className, methodName, "End");
}

Answer 1

应更改JVM的堆大小，但不要将其更改为任何随机数。应根据系统使用的内存修改堆大小。您可以查看this以获取进一步的说明。

Answer 2

使用Aspose.Pdf进行图像转换需要比the default更多的内存。运行程序至少512 MB内存（-Xmx512m）。

Java堆空间错误/内存不足错误

2 个答案: