Using Java jsoup to parse a html page and store data

Question

I am trying to use jsoup libraries to parse a html file and get all the data relating to table class="scl_list" as below, which is only a small part of the html page.


        
            Id:
            Name:
            Serial:
            Status:
            Ladestrom:
            Zähleradresse:
            Zählerstand:
        
        
            7
            7
            c3001c0020333347156a66
            Idle
            16.0
            40100021
            12464.25
        
        
            21
            21
            c3002a003c343551086869
            Idle
            16.0
            540100371
            1219.73

For every , I then need to get every and save the data in a table or vector. Unfortunately I can't find many examples using jsoup which does something similar.

So far I have this, where html_string is my html page, but I'm not sure how to progress. Any help is much appreciated :

Document doc = Jsoup.parse(html_string);
Elements els = doc.getElementsContainingText("table class=\"scl_list\"");

Eritrean · Accepted Answer

Jsoup is a simple and intuitive library. You can find many examples online how to read html tables. Look at the documentation under jsoup cookbook and especially the selector-syntax. To get back to your question, an easy way would be the following:

public static void main(String[] args) {
    String html =   "
" +
                    "        
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "        
" +
                    "        
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "        
" +
                    "        
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "            
" +
                    "        
" +
                    "    Id: Name: Serial: Status: Ladestrom: Zähleradresse: Zählerstand:
7 7 c3001c0020333347156a66 Idle 16.0 40100021 12464.25
21 21 c3002a003c343551086869 Idle 16.0 540100371 1219.73";
    Document doc = Jsoup.parse(html);
    Elements trs = doc.select("table.scl_list tr");
    List> data = new ArrayList<>();
    for(Element tr : trs){
        List row = tr.select("th").stream().map(e -> e.text())
                                .collect(Collectors.toList());
        data.add(row);
    }
    data.forEach(System.out::println);
}

The output should be something like:

[Id:, Name:, Serial:, Status:, Ladestrom:, Zähleradresse:, Zählerstand:]
[7, 7, c3001c0020333347156a66, Idle, 16.0, 40100021, 12464.25]
[21, 21, c3002a003c343551086869, Idle, 16.0, 540100371, 1219.73]

Since the first element seems to contain only the table heading, you can skip it by using a simple for loop and starting from the second element.

Since I assume that your data represents electricity meters, I would recommend you to implement a small class as data container, which could look like this

class Meter{
    int id;
    String name;
    String serial;
    String status;
    double chargingCurrent;
    String address;
    double  meterReading;

    public Meter(List data) {
        this.id = Integer.parseInt(data.get(0));
        this.name = data.get(1);            
        this.serial = data.get(2);
        this.status = data.get(3);
        this.chargingCurrent = Double.parseDouble(data.get(4));
        this.address = data.get(5);
        this.meterReading = Double.parseDouble(data.get(6));
    }
    // getters & setters
}

The code from above could then be rewrittten to something like:

Document doc = Jsoup.parse(html);
Elements trs = doc.select("table.scl_list tr");
List meters = new ArrayList<>();
for(int i = 1; i< trs.size(); i++){
    List row = trs.get(i).select("th").stream().map(e -> e.text())
                            .collect(Collectors.toList());
    meters.add(new Meter(row));
} 
meters.forEach(System.out::println);

with a corresponding toString method the output will look like:

Meter{id=7, name=7, serial=c3001c0020333347156a66, status=Idle, chargingCurrent=16.0, address=40100021, meterReading=12464.25}
Meter{id=21, name=21, serial=c3002a003c343551086869, status=Idle, chargingCurrent=16.0, address=540100371, meterReading=1219.73}

Using Java jsoup to parse a html page and store data

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