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我正在解析来自如下所示的 Web 服务的数据：我只能解析两个值，它们是 status 和 bal，接下来我得到空指针异常。我只能检索状态和 lname。谁能告诉我这是什么问题。我得到状态 = 1，这是正确的，bal = Finn，其余为空。

XML:

<root>
<response>
<status>1</status>
<bal>3.69 EUR</bal>
<cur>EUR</cur>
<acc>2974342749</acc>
<fname>Welcome To</fname>
<lname>Finn</lname>
</response>
</root>

代码：

主要活动

btn.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                new Communicator().execute();
            }
        });
}

public class Communicator extends AsyncTask<String, String, SitesList1>
{
    @Override
        protected SitesList1 doInBackground(String... params) {
            try {
                    SAXParserFactory spf = SAXParserFactory.newInstance();
                    SAXParser sp = spf.newSAXParser();
                    XMLReader xr = sp.getXMLReader();

                    URL sourceUrl = new URL("XXXXX![enter image description here][2]");
                    MyXMLHandler1 myXMLHandler1 = new MyXMLHandler1();
                    xr.setContentHandler(myXMLHandler1);
                    xr.parse(new InputSource(sourceUrl.openStream()));
            } catch (Exception e) {
                System.out.println("XML Pasing Excpetion = " + e);
            }

            sitesList1 = MyXMLHandler1.sitesList1;

            return sitesList1;
        }

        @Override
        protected void onPreExecute() 
        {
            super.onPreExecute();
        }

        @SuppressWarnings("deprecation")
        @Override
        protected void onPostExecute(SitesList1 result) 
        {
                status = sitesList1.getStatus().toString();
                System.out.println("status"+status);
                bal = sitesList1.getBal().toString();
                System.out.println("bal"+bal);
                cur = sitesList1.getCur().toString();
                System.out.println("cur"+cur);
                acc = sitesList1.getAcc().toString();
                System.out.println("acc"+acc);
                fname = sitesList1.getFname().toString();
                System.out.println("fname"+fname);
                lname = sitesList1.getLname().toString();
                System.out.println("lname"+lname);

        }
    }

处理程序：

公共类 MyXMLHandler1 扩展 DefaultHandler{

Boolean currentElement = false;
String currentValue = null;
public static SitesList1 sitesList1 = null;

public  SitesList1 getSitesList1() {
    return sitesList1;
}

public  void setSitesList1(SitesList1 sitesList1) {
    this.sitesList1 = sitesList1;
}

@Override
public void startElement(String uri, String localName, String qName,
        Attributes attributes) throws SAXException {

    currentElement = true;

    if (localName.equals("root")) {
        sitesList1 = new SitesList1();
    }
}

@Override
public void endElement(String uri, String localName, String qName)
        throws SAXException {

    currentElement = false;

    if (localName.equalsIgnoreCase("status"))
        sitesList1.setStatus(currentValue);
    else if (localName.equalsIgnoreCase("bal"))
        sitesList1.setBal(currentValue);
    else if (localName.equalsIgnoreCase("cur"))
        sitesList1.setBal(currentValue);
    else if (localName.equalsIgnoreCase("acc"))
        sitesList1.setBal(currentValue);
    else if (localName.equalsIgnoreCase("fname"))
        sitesList1.setBal(currentValue);
    else if (localName.equalsIgnoreCase("lname"))
        sitesList1.setBal(currentValue);

}

@Override
public void characters(char[] ch, int start, int length)
        throws SAXException {

    if (currentElement) {
        currentValue = new String(ch, start, length);
        currentElement = false;
    }

}

}

二传手：

公共类 SitesList1 {

private String status;
private String bal;
private String cur;
private String acc;
private String fname;
private String lname;
public String getStatus() {
    return status;
}
public void setStatus(String status) {
    this.status = status;
}
public String getBal() {
    return bal;
}
public void setBal(String bal) {
    this.bal = bal;
}
public String getCur() {
    return cur;
}
public void setCur(String cur) {
    this.cur = cur;
}
public String getAcc() {
    return acc;
}
public void setAcc(String acc) {
    this.acc = acc;
}
public String getFname() {
    return fname;
}
public void setFname(String fname) {
    this.fname = fname;
}
public String getLname() {
    return lname;
}
public void setLname(String lname) {
    this.lname = lname;
}

}

4

1 回答 1

0

问题出在你的characters方法上。您没有currentValue正确重置。尝试这样的事情：

public void characters(char[] ch, int start, int length)
            throws SAXException {
  super.characters(ch, start, length);
  currentValue.append(ch, start, length);
}

public void startDocument() throws SAXException {
super.startDocument();
currentValue= new StringBuilder();
}

然后，在您的endElement方法中，您可以这样做：

public void endElement(String uri, String localName, String qName)
        throws SAXException {

    currentElement = false;

    if (localName.equalsIgnoreCase("status"))
        sitesList1.setStatus(currentValue.toString());
    else if (localName.equalsIgnoreCase("bal"))
        sitesList1.setBal(currentValue.toString());
    else if (localName.equalsIgnoreCase("cur"))
        sitesList1.setCur(currentValue.toString());
    else if (localName.equalsIgnoreCase("acc"))
        sitesList1.setAcc(currentValue.toString());
    else if (localName.equalsIgnoreCase("fname"))
        sitesList1.setFname(currentValue.toString());
    else if (localName.equalsIgnoreCase("lname"))
        sitesList1.setLname(currentValue.toString());

   //flush out the StringBuilder so you can start again
   curentValue.setLength(0);

}
于 2012-10-24T19:23:57.320 回答