我想将大型xml分成小块.我正在使用VTDGen将xml文件拆分成小块,它适用于文件大小< 2 GB. VTD-xml使用IN-Memory来解析xml,我不想将xml加载到内存中.所以我试图使用VTDGenHuge映射内存. 代码适用于VTDGen,但是当我使用VTDGenHuge它不起作用.

String prefix = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"+"\n";

String suffix = "\n\n";

try {

VTDGenHuge vg = new VTDGenHuge();

if (vg.parseFile("C:\\Users\\abc\\Desktop\\latestxml\\Input_1.xml", true,VTDGenHuge.MEM_MAPPED)) {

int splitBy = ;

System.out.println("Started time"+ new Date());

VTDNavHuge vn = vg.getNav();

AutoPilotHuge ap = new AutoPilotHuge(vn);

ap.selectXPath("/Employees/Employee");

FastLongBuffer flb = new FastLongBuffer(4);

int i;

byte[] xml = vn.getXML().getBytes();

while ((i = ap.evalXPath()) != -1) {

flb.append(vn.getElementFragment());

}

int size = flb.size();

if (size != 0) {

File fo = null;

FileOutputStream fos = null;

for (int k = 0; k < size; k++) {

if (k % splitBy == 0) {

if (fo != null) {

fos.write(suffix.getBytes());

fos.close();

fo = null;

}

}

if (fo == null) {

fo = new File("C:\\Users\\abc\\Desktop\\Test\\xml\\"+"out" + k + ".xml");

fos = new FileOutputStream(fo);

fos.write(prefix.getBytes());

}

fos.write("\n".getBytes());

fos.write(xml, flb.lower32At(k), flb.upper32At(k));

}

if (fo != null) {

fos.write(suffix.getBytes());

fos.close();

fo = null;

}

}

}

} catch (Exception e) {

e.printStackTrace();

}

我得到NUll值为“byte [] xml = vn.getXML().getBytes();”

当你做syso vn.getXML()时,你得到了对象的价值.但是“getBytes()”返回null.我不知道为什么.但是如果你做“byteAt(x)”x =任何长值它返回值.

我的xml文件是：

29

Pankaj

Male

Java Developer

35

Lisa

Female

CEO

40

Tom

Male

Manager

29

Pankaj

Male

Java Developer

35

Lisa

Female

CEO

40

Tom

Male

Manager

我想这样出来.

29

Pankaj

Male

Java Developer

35

Lisa

Female

CEO

40

Tom

Male

Manager

29

Pankaj

Male

Java Developer

35

Lisa

Female

CEO

40

Tom

Male

Manager