Android：如何解析这种XML

Question

我有一个XML文档，我需要解析以便为每个项目提取以下值：

<title>
<description>
<articleDate>
<story>
<author>
<photo>
<caption>

我正在尝试使用DOM，但是我迷失了，因为每个节点

<item>

根的

<channel> 

有3个孩子：

<article>
<media> 
<link>

Answer 1

也许这会有所帮助： http : //www.mkyong.com/java/how-to-modify-xml-file-in-java-dom-parser/

如何在Android中以XML附加标签？

另一个例子：

final String xmlFile = "YourFile.xml";
    ArrayList<String> userData = new ArrayList<String>();
    FileInputStream fis;
    InputStreamReader isr;
    String data = null;
    try {
        fis = c.openFileInput(xmlFile);
        isr = new InputStreamReader(fis);
        char[] inputBuffer = new char[fis.available()];
        isr.read(inputBuffer);
        data = new String(inputBuffer);
        isr.close();
        fis.close();
    } catch (FileNotFoundException e3) {
        // TODO Auto-generated catch block
        e3.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    XmlPullParserFactory factory = null;
    try {
        factory = XmlPullParserFactory.newInstance();
    } catch (XmlPullParserException e2) {
        // TODO Auto-generated catch block
        e2.printStackTrace();
    }
    factory.setNamespaceAware(true);
    XmlPullParser xpp = null;
    try {
        xpp = factory.newPullParser();
    } catch (XmlPullParserException e2) {
        // TODO Auto-generated catch block
        e2.printStackTrace();
    }
    try {
        xpp.setInput(new StringReader(data));
    } catch (XmlPullParserException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    int eventType = 0;
    try {
        eventType = xpp.getEventType();
    } catch (XmlPullParserException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    while (eventType != XmlPullParser.END_DOCUMENT) {
        if (eventType == XmlPullParser.START_DOCUMENT) {
            System.out.println("Start document");
        } else if (eventType == XmlPullParser.START_TAG) {
            System.out.println("Start tag " + xpp.getName());

        } else if (eventType == XmlPullParser.END_TAG) {
            System.out.println("End tag " + xpp.getName());
        } else if (eventType == XmlPullParser.TEXT) {
            userData.add(xpp.getText());
            System.out.println(xpp.getText());
        }
        try {
            eventType = xpp.next();
        } catch (XmlPullParserException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}   

Answer 2

item是您的根。您必须使用sax解析器来粗化这个xml。 请看这里

Answer 3

使用SAX取得了很多成功，它既快速又简单。 我从下面展示了基于模板的解析器生成器的一些网站上看到了这个简单的“递归”方法的想法。 我只是手工完成，而是从“ DefaultHandler”类扩展而来。

真正的窍门是，每个对象类型都有其自己的“ DefaultHandler”扩展名，该扩展名知道如何解析THAT类型以及仅解析该类型。 这使得重构和重用解析器成为可能，从而使XML和解析器成为可能。 然后，每当看到某种类型的新子'element'的开始时，就创建一个空的子容器，并将其扩展为'DefaultHandler'。 将当前处理程序设置为该类型的处理程序，然后递归砍掉它。

我也可以对此进行改进，例如将一些通用方法推到扩展“ DefaultHandler”的我自己的基类中。 我还创建了“ IXMLSerializer”接口，以便可以快速将其写出。 也许还有更好的方法。

从SAX中脱颖而出

基于此，我想出了一种策略，首先为每种元素类型创建对象。

public class CollectionType implements IXMLSerializer{

public static final String  TYPE_TAG = "Collection";

protected IdentityType identity;
protected List<PropertyType> property;
protected List<ItemReferenceType> itemReference;
protected List<SporeType> spore;
protected List<RegionType> region;
protected List<BackpackItemType> backpackItem;


/**
 * Gets the value of the identity property.
 * 
 * @return
 *     possible object is
 *     {@link IdentityType }
 *     
 */
public IdentityType getIdentity() {
    return identity;
}

/**
 * Sets the value of the identity property.
 * 
 * @param value
 *     allowed object is
 *     {@link IdentityType }
 *     
 */
public void setIdentity(IdentityType value) {
    this.identity = value;
}


/**
 * Gets the value of the property property.
 * 
 * <p>
 * This accessor method returns a reference to the live list,
 * not a snapshot. Therefore any modification you make to the
 * returned list will be present inside the JAXB object.
 * This is why there is not a <CODE>set</CODE> method for the property property.
 * 
 * <p>
 * For example, to add a new item, do as follows:
 * <pre>
 *    getProperty().add(newItem);
 * </pre>
 * 
 * 
 * <p>
 * Objects of the following type(s) are allowed in the list
 * {@link PropertyType }
 * 
 * 
 */
public List<PropertyType> getProperty() {
    if (property == null) {
        property = new ArrayList<PropertyType>();
    }
    return this.property;
}

/**
 * Gets the value of the itemReference property.
 * 
 * <p>
 * This accessor method returns a reference to the live list,
 * not a snapshot. Therefore any modification you make to the
 * returned list will be present inside the JAXB object.
 * This is why there is not a <CODE>set</CODE> method for the itemReference property.
 * 
 * <p>
 * For example, to add a new item, do as follows:
 * <pre>
 *    getItemReference().add(newItem);
 * </pre>
 * 
 * 
 * <p>
 * Objects of the following type(s) are allowed in the list
 * {@link ItemReferenceType }
 * 
 * 
 */
public List<ItemReferenceType> getItemReference() {
    if (itemReference == null) {
        itemReference = new ArrayList<ItemReferenceType>();
    }
    return this.itemReference;
}

/**
 * Gets the value of the spore property.
 * 
 * <p>
 * This accessor method returns a reference to the live list,
 * not a snapshot. Therefore any modification you make to the
 * returned list will be present inside the JAXB object.
 * This is why there is not a <CODE>set</CODE> method for the spore property.
 * 
 * <p>
 * For example, to add a new item, do as follows:
 * <pre>
 *    getSpore().add(newItem);
 * </pre>
 * 
 * 
 * <p>
 * Objects of the following type(s) are allowed in the list
 * {@link SporeType }
 * 
 * 
 */
public List<SporeType> getSpore() {
    if (spore == null) {
        spore = new ArrayList<SporeType>();
    }
    return this.spore;
}

/**
 * Gets the value of the region property.
 * 
 * <p>
 * This accessor method returns a reference to the live list,
 * not a snapshot. Therefore any modification you make to the
 * returned list will be present inside the JAXB object.
 * This is why there is not a <CODE>set</CODE> method for the region property.
 * 
 * <p>
 * For example, to add a new item, do as follows:
 * <pre>
 *    getRegion().add(newItem);
 * </pre>
 * 
 * 
 * <p>
 * Objects of the following type(s) are allowed in the list
 * {@link RegionType }
 * 
 * 
 */
public List<RegionType> getRegion() {
    if (region == null) {
        region = new ArrayList<RegionType>();
    }
    return this.region;
}

/**
 * Gets the value of the backpackItem property.
 * 
 * <p>
 * This accessor method returns a reference to the live list,
 * not a snapshot. Therefore any modification you make to the
 * returned list will be present inside the JAXB object.
 * This is why there is not a <CODE>set</CODE> method for the backpackItem property.
 * 
 * <p>
 * For example, to add a new item, do as follows:
 * <pre>
 *    getBackpackItem().add(newItem);
 * </pre>
 * 
 * 
 * <p>
 * Objects of the following type(s) are allowed in the list
 * {@link BackpackItemType }
 * 
 * 
 */
public List<BackpackItemType> getBackpackItem() {
    if (backpackItem == null) {
        backpackItem = new ArrayList<BackpackItemType>();
    }
    return this.backpackItem;
}

@Override
public void serializeType(XmlSerializer serializer, String namespace)
        throws IllegalArgumentException, IllegalStateException, IOException {

    serializer.startTag(namespace, TYPE_TAG);
    getIdentity().serializeType(serializer, namespace);

    Iterator<PropertyType> pItor = getProperty().iterator();
    while (pItor.hasNext()){
        pItor.next().serializeType(serializer, namespace);
    }

    Iterator<ItemReferenceType> iItor = getItemReference().iterator();
    while (iItor.hasNext()){
        iItor.next().serializeType(serializer, namespace);
    }

    Iterator<SporeType> sItor = getSpore().iterator();
    while (sItor.hasNext()){
        sItor.next().serializeType(serializer, namespace);
    }

    Iterator<RegionType> rItor = getRegion().iterator();
    while (rItor.hasNext()){
        rItor.next().serializeType(serializer, namespace);
    }

    Iterator<BackpackItemType> bItor = getBackpackItem().iterator();
    while (bItor.hasNext()){
        bItor.next().serializeType(serializer, namespace);
    }

    serializer.endTag(namespace, TYPE_TAG);
}

}

然后，我创建一个顶级文档处理程序。

public class DocumentHandler extends DefaultHandler {
public static final String      TAG = DocumentHandler.class.getSimpleName();
private static final boolean    mDebugLogging = true;

SAXParserFactory        mSaxParserFactory;
SAXParser               mSaxParser;
XMLReader               mXmlReader;
Stack<String>           mElementStack = new Stack<String>();

private CollectionType  mCollection = null;
private RequestType     mRequest = null;
private ResponseType    mResponse = null;




public DocumentHandler() throws SAXException, ParserConfigurationException{
    mSaxParserFactory = SAXParserFactory.newInstance();
    mSaxParserFactory.setNamespaceAware(true);      //  Must be set true, otherwise no attributes!
    //m_saxParserFactory.setFeature("http://xml.org/sax/features/namespaces", true);
    //m_saxParserFactory.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
    mSaxParser = mSaxParserFactory.newSAXParser();

    if (mDebugLogging) {
        Log.d(TAG, "SAX parser namespace aware? " + mSaxParser.isNamespaceAware());
        Log.d(TAG, "SAX parser is validating? " + mSaxParser.isValidating());
    }
    mXmlReader = mSaxParser.getXMLReader();
}

@Override
public void endDocument() throws SAXException {
    if (mDebugLogging) {
        Log.d(TAG, "Beginning Document Parse");
    }
    super.endDocument();
}




@Override
public void startDocument() throws SAXException {
    if (mDebugLogging) {
        Log.d(TAG, "Ending Document Parse");
    }
    super.startDocument();
}


@Override
public void startElement(java.lang.String uri, java.lang.String localName, java.lang.String qName, Attributes attributes) throws SAXException {
    if (qName.equals("Collection")) {
        mCollection = new CollectionType();
        final DefaultHandler handler = new CollectionHandler(mElementStack, mCollection, attributes, mXmlReader, this);
        mElementStack.push ("ServerResponse");
        mXmlReader.setContentHandler (handler);
    }
    else if (qName.equals("Request")){
        mRequest = new RequestType();
        final DefaultHandler handler = new RequestHandler(mElementStack, mRequest, attributes, mXmlReader, this);
        mElementStack.push("Request");
        mXmlReader.setContentHandler(handler);
    }
    else if (qName.equals("Response")){
        mResponse = new ResponseType();
        final DefaultHandler handler = new ResponseHandler(mElementStack, mResponse, attributes, mXmlReader, this);
        mElementStack.push("Response");
        mXmlReader.setContentHandler(handler);
    }
}


@Override
public void endElement(java.lang.String uri, java.lang.String localName, java.lang.String qName) throws SAXException {}


public void parse(InputSource is) throws SAXException, IOException {
    mXmlReader.setContentHandler(this);
    mXmlReader.parse(is);
}


public RequestType parseRequest(InputStream inStream) throws SAXException, IOException {
    final InputSource inSource = new InputSource(inStream);
    parse(inSource);
    return mRequest;
}

public CollectionType parseCollection(InputStream inStream) throws SAXException, IOException {
    final InputSource inSource = new InputSource(inStream);
    parse(inSource);
    return mCollection;
}

public ResponseType parseResponse(InputStream inStream) throws SAXException, IOException {
    final InputSource inSource = new InputSource(inStream);
    parse(inSource);
    return mResponse;
}

}

然后我为每种类型扩展“ DefaultHandler”：

公共类CollectionHandler扩展DefaultHandler {私有最终CharArrayWriter m_textBuffer = new CharArrayWriter（）; 私有最终堆栈m_elementStack; 私有最终DefaultHandler m_parent; 私有最终XMLReader m_parser;

private final CollectionType            m_collection;

public CollectionHandler(Stack<String> path, CollectionType collection, Attributes attributes, XMLReader parser, DefaultHandler parent) throws SAXException{
    m_elementStack = path;
    m_collection = collection;
    m_parser = parser;
    m_parent = parent;
    start(attributes);
}

private void start(Attributes attributes){}


@Override
public void startElement(java.lang.String uri, java.lang.String localName, java.lang.String qName, Attributes attributes) throws SAXException {
    m_textBuffer.reset();

    if (qName.equals("Identity")){
        final IdentityType identity = new IdentityType();
        m_collection.setIdentity(identity);
        final DefaultHandler handler = new IdentityHandler(m_elementStack, identity, attributes, m_parser, this);
        m_elementStack.push("Identity");
        m_parser.setContentHandler(handler);
    }

    if (qName.equals("BackpackItem")){
        final BackpackItemType backpackItem = new BackpackItemType();
        m_collection.getBackpackItem().add(backpackItem);
        final DefaultHandler handler = new BackpackItemHandler(m_elementStack, backpackItem, attributes, m_parser, this);
        m_elementStack.push("BackpackItem");
        m_parser.setContentHandler(handler);
    }

    else if (qName.equals("ItemReference")){
        final ItemReferenceType itemReference = new ItemReferenceType();
        m_collection.getItemReference().add(itemReference);
        final DefaultHandler handler = new ItemReferenceHandler(m_elementStack, itemReference, attributes, m_parser, this);
        m_elementStack.push("ItemReference");
        m_parser.setContentHandler(handler);
    }

    else if (qName.equals("Property")){
        final PropertyType property = new PropertyType();
        m_collection.getProperty().add(property);
        final DefaultHandler handler = new PropertyHandler(m_elementStack, property, attributes, m_parser, this);
        m_elementStack.push("Property");
        m_parser.setContentHandler(handler);
    }

    else if (qName.equals("Region")){
        final RegionType toInsert = new RegionType();
        m_collection.getRegion().add(toInsert);
        final DefaultHandler handler = new RegionHandler(m_elementStack, toInsert, attributes, m_parser, this);
        m_elementStack.push("Region");
        m_parser.setContentHandler(handler);
    }

    else if (qName.equals("Spore")){
        final SporeType toInsert = new SporeType();
        m_collection.getSpore().add(toInsert);
        final DefaultHandler handler = new SporeHandler(m_elementStack, toInsert, attributes, m_parser, this);
        m_elementStack.push ("Spore");
        m_parser.setContentHandler (handler);
    }
}


@Override
public void endElement(java.lang.String uri, java.lang.String localName, java.lang.String qName) throws SAXException {
    if (qName.equals("Collection")){
        m_elementStack.pop();
        m_parser.setContentHandler(m_parent);
    }
}

}