在android中使用sax解析器解析xml文件后获取空值

Question

使用sax解析器解析xml文件后，我得到每个子标记的空值。虽然已解析整个文件，但每个子字段显示的值为null。不会存储值，而是在每个字段中保存null。

XML文件

<markers>
    <setMarker id="56c6b9c4ef263869678b4567" mlat="12.947014112057" mlng="77.62656211853"
        slot_id="morning" />
    <setMarker id="56c6b9c5ef263869678b4568" mlat="12.941744189945" mlng="77.628879547119"
        slot_id="morning" />
    <setMarker id="56c6ba01ef263805688b4567" mlat="12.929865544388" mlng="77.633428573608"
        slot_id="morning" />
    <setMarker id="56c6ba11ef2638c3668b4569" mlat="12.93630685197" mlng="77.613000869751"
        slot_id="morning" />
    <setMarker id="56c6ba1aef263814688b4567" mlat="12.944755587651" mlng="77.617979049683"
        slot_id="morning" />
    <setMarker id="56c6ba2bef26383e678b4567" mlat="12.928359760197" mlng="77.609052658081"
        slot_id="morning" />
</marker>

LocationDetails.java

public class LocationDetails {
    public String lattitude;
    public String longitude;
    public String slotId;

    public LocationDetails(String lattitude, String longitude, String slotId) {
        this.lattitude = lattitude;
        this.longitude = longitude;
        this.slotId = slotId;
    }

    public LocationDetails() {

    }

    public String getLattitude() {

        return lattitude;
    }

    public void setLattitude(String lattitude) {
        this.lattitude = lattitude;
    }

    public String getLongitude() {
        return longitude;
    }

    public void setLongitude(String longitude) {
        this.longitude = longitude;
    }

    public String getSlotId() {
        return slotId;
    }

    public void setSlotId(String slotId) {
        this.slotId = slotId;
    }

    @Override
    public String toString() {
        return "LocationDetails{" +
                "lattitude='" + lattitude + '\'' +
                ", longitude='" + longitude + '\'' +
                ", slotId='" + slotId + '\'' +
                '}';
    }

}

SAXXmlHandler.java文件

 private List<LocationDetails> locations;
    private String tempVal;
    private LocationDetails tempLocation = null;
    Boolean currentElement = false;

    public SAXXmlHandler() {
        locations = new ArrayList<>();
    }

    public List<LocationDetails> getLocations() {
        return locations;
    }
    @Override
    public void startElement(String uri, String localName, String qName,
                             Attributes attributes) throws SAXException {
        // reset
        currentElement = true;
        tempVal = "";
        if (qName.equalsIgnoreCase("setMarker")) {
            tempLocation = new LocationDetails();
            Log.d("testing", tempLocation.toString());
        }
    }

    @Override
    public void characters(char[] ch, int start, int length)
            throws SAXException {
        if (currentElement) {
            Log.d("testone", tempVal);
            tempVal = tempVal +  new String(ch, start, length);
            Log.d("testTwo", tempVal);
        }
    }

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

        currentElement = false;

        if (qName.equalsIgnoreCase("setMarker")) {
            // add it to the list
            locations.add(tempLocation);
        } else if (qName.equalsIgnoreCase("mlat")) {
            tempLocation.setLattitude(tempVal);
        } else if (qName.equalsIgnoreCase("mlng")) {
            tempLocation.setLongitude(tempVal);
        } else if (qName.equalsIgnoreCase("slot_id")) {
            tempLocation.setSlotId(tempVal);
        }
    }
}

MainActivity.java

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        list = null;

        list = parse(getResources().openRawResource(R.raw.location_data));

        Log.d("testing", list.toString());

    }


    @Override
    public void onResume() {
        super.onResume();
    }

    @Override
    public void onPause() {
        super.onPause();
    }

    public List<LocationDetails> parse(InputStream inputStream) {
        List<LocationDetails> locations = null;
        try {
            SAXParserFactory spf = SAXParserFactory.newInstance();
            SAXParser sp = spf.newSAXParser();
            XMLReader xr = sp.getXMLReader();
            SAXXmlHandler saxHandler = new SAXXmlHandler();
            xr.setContentHandler(saxHandler);
            InputSource inputSource = new InputSource(inputStream);
            xr.parse(inputSource);
            locations = saxHandler.getLocations();

        } catch (Exception e) {
            Log.d("testing", "SAXXMLParser: parse() failed");
            e.printStackTrace();
        }

        return locations;
    }

android监听调试结果

02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}
02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}
02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}
02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}
02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}
02-29 21:52:13.944 6342-6342/? D/testing: LocationDetails{lattitude='null', longitude='null', slotId='null'}