使用Jsoup提取HTML

Question

I've been studying the example of Jsoup for data extraction and extracts an example of this link

Jsoup

But I tried to manipulate the sample to extract data from a Div instead of a Meta attribute and could not.

I want to load the posts that people publish on a particular blog and loads them in the App page.

Can anyone help me to modify this code to get the DIV data.

package com.androidbegin.jsouptutorial;

import java.io.IOException;
import java.io.InputStream;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.select.Elements;

import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends Activity {

    // URL Address
    String url = "http://www.androidbegin.com";
    ProgressDialog mProgressDialog;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Locate the Buttons in activity_main.xml
        Button titlebutton = (Button) findViewById(R.id.titlebutton);
        Button descbutton = (Button) findViewById(R.id.descbutton);
        Button logobutton = (Button) findViewById(R.id.logobutton);

        // Capture button click
        titlebutton.setOnClickListener(new OnClickListener() {
            public void onClick(View arg0) {
                // Execute Title AsyncTask
                new Title().execute();
            }
        });

        // Capture button click
        descbutton.setOnClickListener(new OnClickListener() {
            public void onClick(View arg0) {
                // Execute Description AsyncTask
                new Description().execute();
            }
        });

        // Capture button click
        logobutton.setOnClickListener(new OnClickListener() {
            public void onClick(View arg0) {
                // Execute Logo AsyncTask
                new Logo().execute();
            }
        });

    }

    // Title AsyncTask
    private class Title extends AsyncTask<Void, Void, Void> {
        String title;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mProgressDialog = new ProgressDialog(MainActivity.this);
            mProgressDialog.setTitle("Android Basic JSoup Tutorial");
            mProgressDialog.setMessage("Loading...");
            mProgressDialog.setIndeterminate(false);
            mProgressDialog.show();
        }

        @Override
        protected Void doInBackground(Void... params) {
            try {
                // Connect to the web site
                Document document = Jsoup.connect(url).get();
                // Get the html document title
                title = document.title();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            // Set title into TextView
            TextView txttitle = (TextView) findViewById(R.id.titletxt);
            txttitle.setText(title);
            mProgressDialog.dismiss();
        }
    }

    // Description AsyncTask
    private class Description extends AsyncTask<Void, Void, Void> {
        String desc;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mProgressDialog = new ProgressDialog(MainActivity.this);
            mProgressDialog.setTitle("Android Basic JSoup Tutorial");
            mProgressDialog.setMessage("Loading...");
            mProgressDialog.setIndeterminate(false);
            mProgressDialog.show();
        }

        @Override
        protected Void doInBackground(Void... params) {
            try {
                // Connect to the web site
                Document document = Jsoup.connect(url).get();
                // Using Elements to get the Meta data
                Elements description = document
                        .select("meta[name=description]");
                // Locate the content attribute
                desc = description.attr("content");
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            // Set description into TextView
            TextView txtdesc = (TextView) findViewById(R.id.desctxt);
            txtdesc.setText(desc);
            mProgressDialog.dismiss();
        }
    }

    // Logo AsyncTask
    private class Logo extends AsyncTask<Void, Void, Void> {
        Bitmap bitmap;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mProgressDialog = new ProgressDialog(MainActivity.this);
            mProgressDialog.setTitle("Android Basic JSoup Tutorial");
            mProgressDialog.setMessage("Loading...");
            mProgressDialog.setIndeterminate(false);
            mProgressDialog.show();
        }

        @Override
        protected Void doInBackground(Void... params) {

            try {
                // Connect to the web site
                Document document = Jsoup.connect(url).get();
                // Using Elements to get the class data
                Elements img = document.select("a[class=brand brand-image] img[src]");
                // Locate the src attribute
                String imgSrc = img.attr("src");
                // Download image from URL
                InputStream input = new java.net.URL(imgSrc).openStream();
                // Decode Bitmap
                bitmap = BitmapFactory.decodeStream(input);

            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            // Set downloaded image into ImageView
            ImageView logoimg = (ImageView) findViewById(R.id.logo);
            logoimg.setImageBitmap(bitmap);
            mProgressDialog.dismiss();
        }
    }
}

This is the site structure:

<div class="postWrapper" id="post162">

<div class="postTitle">

<h2> Title to post </h2>

<div class="fb-custom-share" data-url="http://url...">

</div>

<div class="date"> 26 de janeiro de 2015 </div>

</div>

<div class="postContent">

content

</div>

Answer 1

I don't really get what you are trying extract from HTML content above. Hence I will list a few examples below to help you.

private static void test() {
    Document doc = null;
    Elements dateDivs = null;
    Elements postContentDivs = null;
    Elements fbCustomShareDivs = null;
    Element specificIdDiv = null;

    try {
        doc = Jsoup.connect(url).get();

        /** First part of example, I assume all elements are unique in term of classname, which means for eg there is only one DIV element with date as classname **/
        /** Find all SPAN element with matched CLASS name **/
        dateDivs = doc.select("div.date");

        if (dateDivs.size() > 0) {
            String date = dateDivs.get(0).text();
            System.out.println("date: " + date);
        }
        else {
            System.out.println("No DIV element found with class date.");
        }

        /** Find all SPAN element with matched CLASS name **/
        postContentDivs = doc.select("div.postContent");

        if (postContentDivs.size() > 0) {
            String postContent = postContentDivs.get(0).text();
            System.out.println("postContent: " + postContent);
        }
        else {
            System.out.println("No DIV element found with postContentDivs date.");
        }

        /** Find all SPAN element with matched CLASS name **/
        fbCustomShareDivs = doc.select("div.fb-custom-share");

        if (fbCustomShareDivs.size() > 0) {
            String dataurl = fbCustomShareDivs.get(0).attr("data-url");
            System.out.println("dataurl: " + dataurl);
        }
        else {
            System.out.println("No DIV element found with fb-custom-share date.");
        }

        /** Second part of example **/
        /** If elements are not unique in term of class name, then use following code to retrieve DIV with ID first. **/
        /** Then only continue to retrieve elements inside DIV id post162 **/
        specificIdDiv = doc.getElementById("post162");

        if (specificIdDiv != null) {
            postContentDivs = specificIdDiv.select("div.postContent");

            if (postContentDivs.size() > 0) {
                String postContent = postContentDivs.get(0).text();
                System.out.println("postContent: " + postContent);
            }
            else {
                System.out.println("No DIV element found with postContentDivs date.");
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}