从HTML文件中取出JS加密需要的参数，并调用js内的加密算法

Posted 2021-02-13 末末无闻

背景，爬虫程序需要模拟登陆，账号密码是经js加密的，加密所需的参数需要从html页面中取出

import javax.script.Invocable;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class ScriptEngineTest {
    public static void main(String[] args) throws IOException, ScriptException, NoSuchMethodException {
        ScriptEngineManager manager = new ScriptEngineManager();
        ScriptEngine engine = manager.getEngineByName("javascript");
        String jsFileName = "src/main/resources/static/ss.js";
        String htmlFileName = "src/main/resources/static/url.html";
        Pattern pattern = Pattern.compile(""10001", "", "(.*?)"");
        String htmldatas = readfile(htmlFileName);
        String key = getkey(pattern, htmldatas);
        System.out.println("Key=" + key);
        FileReader reader = new FileReader(jsFileName);
        engine.eval(reader);
        if (engine instanceof Invocable) {
            Invocable invoke = (Invocable) engine;
            String c = (String) invoke.invokeFunction("find", "10001", key, "111111");
            System.out.println("加密后：" + c);
        }
        reader.close();
    }


    public static String readfile(String filePath) {
        File file = new File(filePath);
        InputStream input = null;
        try {
            input = new FileInputStream(file);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        StringBuffer buffer = new StringBuffer();
        byte[] bytes = new byte[1024];
        try {
            for (int n; (n = input.read(bytes)) != -1; ) {
                buffer.append(new String(bytes, 0, n, "UTF-8"));
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return buffer.toString();
    }

    public static String getkey(Pattern pattern, String htmldatas) {
        Matcher matcher = pattern.matcher(htmldatas);
        String htmldata = "";
        String key = "";
        if (matcher.find()) {
            htmldata = matcher.group();
            System.out.println("htmldata=" + htmldata);
            String ss[] = htmldata.split(",");
            key = ss[2].replace(""","").trim();
        }
        return key;
    }
}