java - 使用 Jsoup 提取 HTML

Question

我一直在研究Jsoup用于数据提取的示例，并提取了此链接的示例

Jsoup

但我尝试操作示例以从 Div 而不是 Meta 属性中提取数据，但失败了。

我想加载人们在特定博客上发布的帖子并将其加载到应用程序页面中。

谁能帮我修改这段代码来获取DIV数据。

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();
        }
    }
}

这是网站结构:

<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

我真的不明白你想从上面的 HTML 内容中提取什么。因此，我将在下面列出一些示例来帮助您。

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();
    }
}