SaxParser doesn't get full string between the tags

Question

I am using SAX to parse the xml file. I have a tag called image which contains a large base64 string. SAX does not return full string that I need. Here is the SAX Parser that I use.

public class ParseQuestions extends DefaultHandler{
    Question question;

    private Context context;
    public ParseQuestions(Context context){
        this.context=context;
    }

    public List<Question> questions(String filename){  
          try {  
           // obtain and configure a SAX based parser  
           SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();  

           // obtain object for SAX parser  
           SAXParser saxParser = saxParserFactory.newSAXParser();  

           // default handler for SAX handler class  
           // all three methods are written in handler's body  
           DefaultHandler defaultHandler = new DefaultHandler(){  


            String imageTag="close";  



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


             if (qName.equalsIgnoreCase("image")) {  
                  imageTag = "open";  
                 } 
            }  


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


             if (imageTag.equals("open")) {  
                  question.setImage(new String(ch, start, length)); 
             }
            }  


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


        if (qName.equalsIgnoreCase("image")) {  
            imageTag = "close";  
              } 

           };  


           AssetManager mngr = context.getAssets();
           InputStream is = mngr.open(filename);;
           saxParser.parse(is, defaultHandler);  
          } catch (Exception e) {  
           e.printStackTrace();  
          }

         }  
        } 

Any help would be appreciated. Thanks

Answer 1

The characters method can be called more than once for the text within a single pair of open and close tags.

Your code assumes it's only called once, which will frequently be true for small data, but not always.

You need to initialize a buffer in the startElement method for that tag, collect into the buffer in the characters method, and convert the buffer to a string in the endElement.