Question

This is my first time using SAXParser, (I’m using it in Android, but I don’t think that makes a difference for this particular issue) and I’m trying to read in data from an RSS feed. So far, it’s working great for me for the most part, but I’m having trouble when it gets to a tag that contains HTML encoded text (e.g. <a href="http://...). The characters() method only reads in the < as a <, then treats the next set of characters as a separate entity, rather than taking the entire contents at once. I would rather it just read it in as it is, without actually translating the HTML. The code I’m using for my document handler (shortened) is posted below:

@Override
    public void startElement(String uri, String localName, String qName, Attributes attrs) throws SAXException {
        if (localName.equalsIgnoreCase("channel")) {
            inChannel = true;
        }
        if (inChannel) {
            if (newFeed == null) newFeed = new Feed();

            if (localName.equalsIgnoreCase("image")) {
                if (feedImage == null) feedImage = new Image();
                inImage = true;
            }

            if (localName.equalsIgnoreCase("item")) {
                if (newItem == null) newItem = new Item();
                if (itemList == null) itemList = new ArrayList<Item>();
                inItem = true;
            }
        }   
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        if(!inItem) {
            if(!inImage) {
                if(inChannel) {
                    //Reached end of feed
                    if(localName.equalsIgnoreCase("channel")) {
                        newFeed.setItems((ArrayList<Item>)itemList);
                        finalFeed = newFeed;
                        newFeed = null;                     
                        inChannel = false;
                        return;
                    } else if(localName.equalsIgnoreCase("title")) {
                        newFeed.setTitle(currentValue); return;
                    } else if(localName.equalsIgnoreCase("link")) {
                        newFeed.setLink(currentValue); return;
                    } else if(localName.equalsIgnoreCase("description")) {
                        newFeed.setDescription(currentValue); return;
                    } else if(localName.equalsIgnoreCase("language")) {
                        newFeed.setLanguage(currentValue); return;
                    } else if(localName.equalsIgnoreCase("copyright")) {
                        newFeed.setCopyright(currentValue); return;
                    } else if(localName.equalsIgnoreCase("category")) {
                        newFeed.addCategory(currentValue); return;
                    }                       
                }
            }
            else { //is inImage
                //finished with feed image
                if(localName.equalsIgnoreCase("image")) {
                    newFeed.setImage(feedImage);
                    feedImage = null;
                    inImage = false;
                    return;
                } else if (localName.equalsIgnoreCase("url")) {
                    feedImage.setUrl(currentValue); return;
                } else if (localName.equalsIgnoreCase("title")) {
                    feedImage.setTitle(currentValue); return;
                } else if (localName.equalsIgnoreCase("link")) {
                    feedImage.setLink(currentValue); return;
                }
            }
        }
        else { //is inItem
            //finished with news item
            if (localName.equalsIgnoreCase("item")) {
                itemList.add(newItem);
                newItem = null;
                inItem = false;
                return;
            } else if (localName.equalsIgnoreCase("title")) {
                newItem.setTitle(currentValue); return;
            } else if (localName.equalsIgnoreCase("link")) {
                newItem.setLink(currentValue); return;
            } else if (localName.equalsIgnoreCase("description")) {
                newItem.setDescription(currentValue); return;
            } else if (localName.equalsIgnoreCase("author")) {
                newItem.setAuthor(currentValue); return;
            } else if (localName.equalsIgnoreCase("category")) {
                newItem.addCategory(currentValue); return;
            } else if (localName.equalsIgnoreCase("comments")) {
                newItem.setComments(currentValue); return;
            } /*else if (localName.equalsIgnoreCase("enclosure")) {
                 To be implemented later
            }*/ else if (localName.equalsIgnoreCase("guid")) {
                newItem.setGuid(currentValue); return;
            } else if (localName.equalsIgnoreCase("pubDate")) {
                newItem.setPubDate(currentValue); return;
            }           
        }
    }

    @Override
    public void characters(char[] ch, int start, int length) {
        currentValue = new String(ch, start, length);
    }

And an example of the RSS feed I’m trying to parse is this one.

Any ideas?

Answer 1

In case it helps anyone, I was able to solve this issue by using a boolean for every field in which I’m interested in the data. Then I just continued to append to a StringBuilder until I reached a closing tag, after which I took the StringBuilder value, then emptied it, and set my boolean to false.

@Override
    public void startElement(String uri, String localName, String qName, Attributes attrs) throws SAXException {
        sb.delete(0, sb.length());
        if (localName.equalsIgnoreCase("channel")) {
            inChannel = true;
            newFeed = new Feed();
            itemList = new ArrayList<Item>();
        }
        if (inChannel) {            
            if (localName.equalsIgnoreCase("image")) {
                feedImage = new Image();
                inImage = true;
                return;
            }           
            else if (localName.equalsIgnoreCase("item")) {
                newItem = new Item();
                inItem = true;
                return;
            }

            if(inImage) { //set booleans for image elements
                if (localName.equalsIgnoreCase("title")) imgTitle = true;
                else if (localName.equalsIgnoreCase("link")) imgLink = true;
                else if (localName.equalsIgnoreCase("url")) imgURL = true;
                return;
            }           
            else if(inItem) { //set booleans for item elements
                if (localName.equalsIgnoreCase("title")) iTitle = true;
                else if (localName.equalsIgnoreCase("link")) iLink = true;
                else if (localName.equalsIgnoreCase("description")) iDescription = true;
                else if (localName.equalsIgnoreCase("author")) iAuthor = true;
                else if (localName.equalsIgnoreCase("category")) iCategory = true;
                else if (localName.equalsIgnoreCase("comments")) iComments = true;
                else if (localName.equalsIgnoreCase("guid")) iGuid = true;
                else if (localName.equalsIgnoreCase("pubdate")) iPubDate= true;
                else if (localName.equalsIgnoreCase("source")) iSource = true;
                return;
            } else { //set booleans for channel elements
                if (localName.equalsIgnoreCase("title")) fTitle = true;
                else if (localName.equalsIgnoreCase("link")) fLink = true;
                else if (localName.equalsIgnoreCase("description")) fDescription = true;
                else if (localName.equalsIgnoreCase("language")) fLanguage= true;
                else if (localName.equalsIgnoreCase("copyright")) fCopyright = true;
                else if (localName.equalsIgnoreCase("category")) fCategory = true;
                return;
            }
        }       
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        if(inChannel) {
            if(inImage) {
                if (localName.equalsIgnoreCase("title")) {
                    feedImage.setTitle(sb.toString());
                    sb.delete(0, sb.length());
                    imgTitle = false;
                    return;
                }
                else if (localName.equalsIgnoreCase("link")) {
                    feedImage.setLink(sb.toString());
                    sb.delete(0, sb.length());
                    imgLink = false;
                    return;
                }
                else if (localName.equalsIgnoreCase("url")) {
                    feedImage.setUrl(sb.toString());
                    sb.delete(0, sb.length());
                    imgURL = false;
                    return;
                }
                else return;
            } 
            else if(inItem) {
                if (localName.equalsIgnoreCase("item")) {
                    itemList.add(newItem);
                    newItem = null;
                    inItem = false;
                    return;
                } else if (localName.equalsIgnoreCase("title")) {
                    newItem.setTitle(sb.toString()); 
                    sb.delete(0, sb.length());
                    iTitle = false;
                    return;
                } else if (localName.equalsIgnoreCase("link")) {
                    newItem.setLink(sb.toString()); 
                    sb.delete(0, sb.length());
                    iLink = false;
                    return;
                } else if (localName.equalsIgnoreCase("description")) {
                    newItem.setDescription(sb.toString()); 
                    sb.delete(0, sb.length());
                    iDescription = false;
                    return;
                } else if (localName.equalsIgnoreCase("author")) {
                    newItem.setAuthor(sb.toString()); 
                    sb.delete(0, sb.length());
                    iAuthor = false;
                    return;
                } else if (localName.equalsIgnoreCase("category")) {
                    newItem.addCategory(sb.toString()); 
                    sb.delete(0, sb.length());
                    iCategory = false;
                    return;
                } else if (localName.equalsIgnoreCase("comments")) {
                    newItem.setComments(sb.toString());
                    sb.delete(0, sb.length());
                    iComments = false;
                    return;
                } /*else if (localName.equalsIgnoreCase("enclosure")) {
                     To be implemented later
                }*/ else if (localName.equalsIgnoreCase("guid")) {
                    newItem.setGuid(sb.toString()); 
                    sb.delete(0, sb.length());
                    iGuid = false;
                    return;
                } else if (localName.equalsIgnoreCase("pubDate")) {
                    newItem.setPubDate(sb.toString()); 
                    sb.delete(0, sb.length());
                    iPubDate = false;
                    return;
                }
            } 
            else {
                if(localName.equalsIgnoreCase("channel")) {
                    newFeed.setItems((ArrayList<Item>)itemList);
                    finalFeed = newFeed;
                    newFeed = null;                     
                    inChannel = false;
                    return;
                } else if(localName.equalsIgnoreCase("title")) {
                    newFeed.setTitle(currentValue); 
                    sb.delete(0, sb.length());
                    fTitle = false;
                    return;
                } else if(localName.equalsIgnoreCase("link")) {
                    newFeed.setLink(currentValue); 
                    sb.delete(0, sb.length());
                    fLink = false;
                    return;
                } else if(localName.equalsIgnoreCase("description")) {
                    newFeed.setDescription(sb.toString());
                    sb.delete(0, sb.length());
                    fDescription = false;
                    return;
                } else if(localName.equalsIgnoreCase("language")) {
                    newFeed.setLanguage(currentValue); 
                    sb.delete(0, sb.length());
                    fLanguage = false;
                    return;
                } else if(localName.equalsIgnoreCase("copyright")) {
                    newFeed.setCopyright(currentValue); 
                    sb.delete(0, sb.length());
                    fCopyright = false;
                    return;
                } else if(localName.equalsIgnoreCase("category")) {
                    newFeed.addCategory(currentValue); 
                    sb.delete(0, sb.length());
                    fCategory = false;
                    return;
                }
            }
        }
    }

    @Override
    public void characters(char[] ch, int start, int length) {
        sb.append(new String(ch, start, length));
    }