使用Java解析大型XML文件

Question

I'm trying to read a huge XML file(2GB). So, I started of to use STAX and I've to use steam input. Below is the code

filePath = "D:/Data/sample.xml"; //Correct path
String tagContent = null;
XMLInputFactory factory = XMLInputFactory.newInstance();
XMLStreamReader reader = null;
try{
    System.out.println("here");
    reader = factory.createXMLStreamReader(ClassLoader.getSystemResourceAsStream(filePath));
    System.out.println("Reader1:" + reader);
}
catch(Exception e)
{
    System.out.println("Error 4:" + e);
}
System.out.println("Reader2:" + reader);

Output returns error:

here
Error 4:javax.xml.stream.XMLStreamException: java.net.MalformedURLException
Reader2:null

How do I resolve this error?

Answer 1

Method getSystemResourceAsStream opens for reading, a resource of the specified name from the search path used to load classes .

You are going to read a file so open a file stream:

        filePath = "D:/Data/sample.xml"; //Correct path
        String tagContent = null;
        XMLInputFactory factory = XMLInputFactory.newInstance();
        XMLStreamReader reader = null;
        try{
            System.out.println("here");
            reader = factory.createXMLStreamReader(new FileInputStream(new File(filePath)));
            System.out.println("Reader:" + reader);
        }
        catch(Exception e)
        {
            System.out.println("Error 4:" + e);
        }
        System.out.println("Reader:" + reader);

Answer 2

Following line appears to be throwing an exception

reader = factory.createXMLStreamReader(ClassLoader.getSystemResourceAsStream(filePath));

which causes reader to remain null. Most probably class loading is not successful.

Answer 3

我认为您的文件路径不是有效的网址 ：请尝试： file:///D:/Data/sample.xml

Answer 4

ClassLoader.getSystemResourceAsStream(...) is using the system classloader . Just use this.getClass().getResoruceAsStream(...) .