如何使用JSoup从网站获取多个表

Question

I need to get all 9 tables off:

https://www.basketball-reference.com/players/c/collijo01.html

My current code only does 1 table. I switch .first() to .last() which doesn't work. I tried using ("table.totals") to grab a table by name but that also failed.

public static void getData(String url) throws IOException
{
    String fileName = "table.csv";
    FileWriter writer = new FileWriter(fileName);
    Document doc = Jsoup.connect(url).get();
    Element tableElement = doc.select("table").first();

    System.out.println(doc);

    Elements tableHeaderEles = tableElement.select("thead tr th");
    for (int i = 0; i < tableHeaderEles.size(); i++) {
        writer.append(tableHeaderEles.get(i).text());

        if(i != tableHeaderEles.size() -1){             
            writer.append(',');
        }
    }
    writer.append('\n');
    System.out.println();

    Elements tableRowElements = tableElement.select(":not(thead) tr");

    for (int i = 0; i < tableRowElements.size(); i++) {
        Element row = tableRowElements.get(i);
        Elements rowItems = row.select("td");
        for (int j = 0; j < rowItems.size(); j++) {
            writer.append(rowItems.get(j).text());

            if(j != rowItems.size() -1){
                writer.append(',');
            }
        }
        writer.append('\n');
    }

    writer.close();
}

I get the first table from the site perfectly, but unable to advance past that. Does anyone know how to get all tables or grab tables based on ID?

EDIT: if anyone wants to completely test this coding's outputs for themselves

 public static void read(String file) throws IOException
 {
    Scanner scanner = new Scanner(new File(file));
    scanner.useDelimiter(",");
    while(scanner.hasNext()){
        System.out.print(scanner.next()+"|");
    }
    scanner.close();
}

Answer 1

You've already selected all tables but you're explicitly getting only the first one:

Element tableElement = doc.select("table").first();

Instead you can easily iterate over all of them:

Elements tableElements = doc.select("table");
for (Element tableElement : tableElements) {
   // for each of selected tables
}

So after some modifications to get unique filename the code will look like this:

public static void getData(String url) throws IOException {
    String html = Jsoup.connect(url).execute().body();
    // this one is tricky as it contains tables as commented out HTML, and shows them using javascript code
    // so I'm using dirty replace to remove comment tags before parsing to make tables visible to Jsoup
    html = html.replaceAll("<!--", "");
    html = html.replaceAll("-->", "");
    Document doc = Jsoup.parse(html);
    Elements tableElements = doc.select("table");
    int number = 1;
    for (Element tableElement : tableElements) {
        String tableId = tableElement.id();
        if (tableId.isEmpty()) {
            // skip table without id
            continue;
        }
        tableId = " with id " + tableId;
        String fileName = "table" + number++ + tableId + ".csv";
        FileWriter writer = new FileWriter(fileName);

        System.out.println(doc);

        Elements tableHeaderEles = tableElement.select("thead tr th");
        for (int i = 0; i < tableHeaderEles.size(); i++) {
            writer.append(tableHeaderEles.get(i).text());

            if (i != tableHeaderEles.size() - 1) {
                writer.append(',');
            }
        }
        writer.append('\n');
        System.out.println();

        Elements tableRowElements = tableElement.select(":not(thead) tr");

        for (int i = 0; i < tableRowElements.size(); i++) {
            Element row = tableRowElements.get(i);
            Elements rowItems = row.select("td");
            for (int j = 0; j < rowItems.size(); j++) {
                writer.append(rowItems.get(j).text());

                if (j != rowItems.size() - 1) {
                    writer.append(',');
                }
            }
            writer.append('\n');
        }

        writer.close();
    }
}

Answering your second question:

grab tables based on ID

Instead of selecting first table of all tables:

Element tableElement = doc.select("table").first();

select first table of table with id advanced :

Element tableElement = doc.select("table#advanced").first();

Additional advice: The things you give as parameters to select(...) are CSS selectors .