Question

我正在尝试构建组合的SAX / DOM解析器，它将使用SAX解析器来确定我需要的数据块，并将这些块逐个转发到DOM解析器。为此，我使用XLMWriter，它使用PipedInputStream / PipedOutputStream将我需要的块写入InputSource：

public class CombinedReaderObserv {

XMLOutputFactory output = null;
XMLStreamWriter writer = null;
PipedOutputStream out;
PipedInputStream in;
InputSource inpSourse;

public CombinedReaderObserv () throws IOException, XMLStreamException {
    out = new PipedOutputStream();
    in = new PipedInputStream(out);
    inpSourse = new InputSource(in);
    output = XMLOutputFactory.newInstance();
    writer = output.createXMLStreamWriter(out);
}

@Override
public void read(InputStream is) throws Exception {
    //Create SAX parser
    SAXParserFactory SAXfactory = SAXParserFactory.newInstance();
    SAXParser parser = SAXfactory.newSAXParser();
    SAXHandler handler = new SAXHandler();
    parser.parse(is, handler);
    writer.close(); 
}

private class SAXHandler extends DefaultHandler {

    @Override
    public void startElement(String URI,
            String localName,
            String qName,
            Attributes attributes) {
        try {
            //Enables data streaming if found Facility Site starting tag 
            //element and starts streaming data to the InputSource
            switch (qName) {
                case "FacilitySite":
                    write = true;
                    writer.writeStartDocument();
                    writer.writeStartElement("root");
                default:
                    if (write == true) {
                        writer.writeStartElement(qName);
                    }
            }
        } catch (XMLStreamException ex) {
            ex.printStackTrace();
        }
    }

    @Override
    public void endElement(String URI,
            String localName,
            String qName) {
        switch (qName) {
            //ends all XML elements and forvardsthe InputSource object  
            //to parser if found facility site element closing tag 
            case "FacilitySite":
                try {
                    writer.writeEndElement();
                    writer.writeEndElement();
                    writer.writeEndDocument();
                    reader.read(inpSourse); 
                    writer.flush();            //Program stops here
                } catch (Exception ex) {
                    ex.printStackTrace();
                }
                write = false;
                break;
            default:
                if (write == true) {
                    try {
                        writer.writeEndElement();
                    } catch (XMLStreamException ex) {
                        ex.printStackTrace();
                    }
                }
            }
        }
    }
}

问题是在正确解析InputSource对象后，parcer Object继续等待更多输入。在解析之前关闭XML编写器不会导致任何操作，关闭管道连接会导致“管道关闭”异常。

如何让DOM解析器意识到不再有输入？

更新

从Piped切换到ByteArray Streams帮助。

如何完成到InputSource的数据流来解析它

0 个答案: