Java Selenium：如何筛选含指定子元素的info类元素并存入ArrayList

Got it, let's work through this contact info extraction problem to get that existence check logic solid. Here's a straightforward, practical approach to make sure only complete contact entries make it into your ArrayList:

Core Logic Breakdown #

We'll iterate over every info element, check that all three required child elements (n, adr, primary phone) are present, and only add the entry to our list if all three exist.

Step 1: Set Up Your Parsing & List #

Assuming you're using Jsoup (the go-to library for web scraping in Java), start by grabbing all info elements and initializing your ArrayList:

// Parse your HTML content (could be from a URL or string)
Document doc = Jsoup.parse(yourHtmlSource);
Elements allInfoElements = doc.select(".info");

// Initialize your list to hold valid contacts
ArrayList<Contact> validContacts = new ArrayList<>();

Step 2: Add Existence Validation for Required Fields #

For each info element, use selectFirst() to fetch each child element—this returns null if the element doesn't exist, which makes our null check simple and safe:

for (Element infoElement : allInfoElements) {
    // Fetch each required child element
    Element nameElement = infoElement.selectFirst(".n");
    Element addressElement = infoElement.selectFirst(".adr");
    // Note: If the phone class is "primary phone" (space-separated), it's two classes—use .primary.phone to match both
    Element phoneElement = infoElement.selectFirst(".primary.phone");

    // Validate all three elements exist before proceeding
    if (nameElement != null && addressElement != null && phoneElement != null) {
        // Extract clean text (adjust to use html() if you need formatting)
        String name = nameElement.text().trim();
        String address = addressElement.text().trim();
        String phone = phoneElement.text().trim();

        // Add the complete contact to your list
        validContacts.add(new Contact(name, address, phone));
    }
}

Step 3: Create a Contact POJO #

You'll need a simple class to store the contact data neatly:

public class Contact {
    private String name;
    private String address;
    private String phone;

    public Contact(String name, String address, String phone) {
        this.name = name;
        this.address = address;
        this.phone = phone;
    }

    // Add getters/setters if you need to access the data later
    public String getName() { return name; }
    public String getAddress() { return address; }
    public String getPhone() { return phone; }
}

Key Tips #

• Class Selector Note: If the phone element has classes primary and phone (space-separated), .primary.phone is the correct selector (no space) to match elements with both classes.
• Null Safety: Using selectFirst() avoids exceptions that would happen if you used select().get(0) on a missing element.
• Flexibility: Swap text() for html() if you need to preserve nested formatting or links in the address/name fields.

This setup ensures you only collect contacts with all three required pieces of information, skipping any incomplete entries automatically.

内容的提问来源于stack exchange，提问作者ztrition