将InputStream对象转换为String的最佳方法

Question

I have an InputStream object which contains several million file informations (Name, create date, author etc.) in XML format. I've already tried to convert it to String using IOUtils.copy method, but since the size of that information is pretty large it throws an java.lang.OutOfMemoryError , after running for few minutes.

Increasing JVM memory is not an option, since the number of files, which I collect info from, is increasing forever. So can someone suggest me what should I do to solve the issue?

Answer 1

The problem that you are having is the very reason stream based IO exists, it is simply not viable to slurp huge amounts of data into memory before consuming it.

Parse your stream as... a stream! See the Oracle tutorials for more information on stream based XML parsing using SAX.

XMLReader xmlreader =
    SAXParserFactory.newInstance().newSAXParser().getXMLReader();
xmlreader.setContentHandler(new ContentHandler() {
    ...
});

xmlreader.parse(new InputSource(myInputStream));