Aalto XML processor is an ultra-high performance next generation Stax XML processor implementation, implementing both
basic Stax API (
javax.xml.stream) and Stax2 API extension (
In additiona, it also implements SAX2 API.
Additionally Aalto implements a non-blocking (asynchronous) Stax parser; non-blocking API is a minimalistic extension above Stax/Stax2 API to allow indication of "not yet available" token (EVENT_INCOMPLETE) as well as feeding of input (since InputStream can not be used as it blocks)
Aalto is licensed under Apache License 2.0
Blocking XML parsing is done using one of standard interfaces:
Non-blocking parsing interface is extension of basic Stax (and Stax2) API, with extensions defined in 'com.fasterxml.aalto' package::
AsyncXMLInputFactoryoffers factory methods for creating non-blocking parsers
AsyncXMLStreamReaderis extended type that non-blocking parsers implement
AsyncXMLStreamReader.EVENT_INCOMPLETE(value 257; just outside range reserved by Stax API) is used to denote "not yet available" (without more data)
getInputFeeder()is used to access object of type 'AsyncInputFeeder' used to feed input non-blocking way
AsyncInputFeedercontains methods for feeding input.
Typical usage pattern is one where block of input is fed to parser, and zero or more complete events are read using basic 'XMLStreamReader.next()' method; and once 'EVENT_INCOMPLETE' is returned, more input needs to be given. AsyncXMLStreamReader itself does not buffer input beyond a single block; caller is responsible for additional buffering, if any. See Async parsing for details.
AsyncXMLInputFactory is simple; instance may be constructed with or without initial content to parse:
AsyncXMLInputFactory f = new InputFactoryImpl(); AsyncXMLStreamReader<AsyncByteArrayFeeder> parser = f.createAsyncFor(byteArray);
and more content is feed via
AsyncInputFeeder when getting
parser.getInputFeeder().feedInput(b, offset, dataLength);
or, if no more input available, indicate end-of-content with
Aalto dependency is usually added via Maven repository, so something like:
<dependency> <groupId>com.fasterxml</groupId> <artifactId>aalto-xml</artifactId> <version>0.9.11</version> </dependency>