java - 如何使用 XMLStreamReader 多次读取同一 XML 文件

Question

我分三个阶段读取 xml 文件，在每个阶段，我对基于输入参数的不同元素感兴趣。

使用 XMLStreamReader 多次读取一个 xml 文件的最佳方法是什么？

xmlInputFactory = XMLInputFactory.newInstance();
    try {
        XMLStreamReader streamReader xmlInputFactory.createXMLStreamReader(inputStream);

 try {
        while (streamReader .hasNext()) {

其中 inputStream 是 FileInputStream 实例

目前，当我开始第二阶段读取时，我收到流关闭异常或streamReader.hasNext()为假。

Answer 1

将文件加载到内存中并使用 ByteArrayInputStream

File f = ...;
int len = (int)f.length(); // careful: If the life is over 4 gigs this won't work
byte myXML[] = new byte[];
FileInputStream fis = new FileInputStream(f);
int read = fis.read(f); // not guarenteed to read all bytes, but in my experience, this reads all bytes
if (read != len) throw RuntimeExcption("Didn't read everything");

// Now you can create as many XMLStreamReaders as you want like

    try {
        XMLStreamReader streamReader xmlInputFactory.createXMLStreamReader(new ByteArrayInputStream(buf));