我正在使用jsoup来解析网站上的HTML。有两个选项列表是从javascript文件中的多维数组动态创建的。由于其动态创建的jsoup无法解析html中的结果。但是，我需要的所有数据都位于JS文件中。理想情况下，我希望能够定期加载文件并将此文件中的数组数据持久/刷新到Android应用程序上的本地数据库。有问题的JS文件是here，显示列表的网站是here有没有办法下载这个文件的选定方面来在Java中操作它，就像在html中使用DOM一样？
答案 0 :(得分：1)
您可以使用WebView with a JavascriptInterface，也可以使用Rhino引擎。后一种方法如下所述。
首先download Rhino（当前版本为1.7.7.1）
将rhino jar（例如rhino-1.7.7.1.jar）从lib文件夹复制到android项目中的libs文件夹。
将依赖项添加到build.gradle（Module：app）文件中：
dependencies {
[other dependencies]
compile files('libs/rhino-1.7.7.1.jar')
}
以下示例活动加载脚本文件，修改脚本（请参阅注释）并执行函数以填充数组。然后检索数组并将其作为数组存储在java：
中<强> MainActivity.java
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import org.mozilla.javascript.Context;
import org.mozilla.javascript.Function;
import org.mozilla.javascript.NativeArray;
import org.mozilla.javascript.Scriptable;
import org.mozilla.javascript.ScriptableObject;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
public class MainActivity extends AppCompatActivity {
String[][] deptarray;
String[][] zonearray;
String[][] roomarray;
String[][] studsetarrayByCode;
String[][] studsetarrayByTitle;
String[][] staffarray;
String[][] roombydeptarray;
String[][] modulearrayByCode;
String[][] modulearrayByTitle;
String[][] progarrayByCode;
String[][] progarrayByTitle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new RetrieveJSFileTask().execute("http://timetables.itsligo.ie:81/js/filter.js");
}
class RetrieveJSFileTask extends AsyncTask<String, Void, String> {
protected String doInBackground(String... urls) {
try {
URL url = new URL(urls[0]);
BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
StringBuilder builder = new StringBuilder();
String line="";
boolean store = false;
builder.append("var deptarray;");
builder.append("var zonearray;");
while ((line = in.readLine()) != null) {
if(line.startsWith("var roomarray = ")||line.startsWith("var studsetarray =")||line.startsWith("var staffarray =")||line.startsWith("var roombydeptarray =")||line.startsWith("var modulearray =")||line.startsWith("var progarray =")){
builder.append(line);
continue;
}else if(line.contains("function PopulateFilter(strZoneOrDept, cbxFilter)")){ // populates dept and zone
store = true;
}
else if(line.contains("function FilterModulesByCode(Form) {") || line.contains("function FilterModulesByTitle(Form) {") ){ // populates module
store = true;
}
else if(line.contains("function FilterStudentSetsByCode(Form) {") || line.contains("function FilterStudentSetsByTitle(Form) {") ){ // populates studset
store = true;
}
else if(line.contains("function FilterRooms(Form) {") ){ // populates room
store = true;
}
else if(line.contains("function FilterRoomsByDept(Form) {") ){ // populates roombydept
store = true;
}
else if( line.contains("function FilterProgrammesByCode(Form) {") || line.contains("function FilterProgrammesByTitle(Form) {") ){ // populates prog
store = true;
}
else if(line.contains("function FilterStaff(Form) {") ){ // populates staff
store = true;
}
else if(line.contains("var zonearray") || line.contains("var deptarray") ){ // make zone and dept global
line = line.replace("var ", "");
}
if(store){
builder.append(line);
}
if( line.contains("zonearray.sort()") || line.contains("modulearray.sort();") || line.contains("studsetarray.sort();") || line.contains("roomarray.sort();") || line.contains(" roombydeptarray.sort();") || line.contains(" progarray.sort();") || line.contains("staffarray.sort();") ){
builder.append("return;}"); // stop function execution after population of arrays
store = false;
continue;
}
}
in.close();
return builder.toString();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
protected void onPostExecute(String jsSource) {
if(jsSource==null) return;
Context rhino = Context.enter();
// Turn off optimization to make Rhino Android compatible
rhino.setOptimizationLevel(-1);
Scriptable scope = rhino.initStandardObjects();
ScriptableObject.putProperty(scope, "javaContext", Context.javaToJS(this, scope));
rhino.evaluateString(scope, jsSource, "ScriptAPI", 1, null);
((Function)scope.get("PopulateFilter", scope)).call(rhino, scope, scope, new Object[]{null,null});
deptarray = getArray((NativeArray)scope.get("deptarray", scope));
zonearray = getArray((NativeArray)scope.get("zonearray", scope));
((Function)scope.get("FilterModulesByCode", scope)).call(rhino, scope, scope, new Object[]{null});
modulearrayByCode = getArray((NativeArray)scope.get("modulearray", scope));
((Function)scope.get("FilterModulesByTitle", scope)).call(rhino, scope, scope, new Object[]{null});
modulearrayByTitle = getArray((NativeArray)scope.get("modulearray", scope));
((Function)scope.get("FilterStudentSetsByCode", scope)).call(rhino, scope, scope, new Object[]{null});
studsetarrayByCode = getArray((NativeArray)scope.get("studsetarray", scope));
((Function)scope.get("FilterStudentSetsByTitle", scope)).call(rhino, scope, scope, new Object[]{null});
studsetarrayByTitle = getArray((NativeArray)scope.get("studsetarray", scope));
((Function)scope.get("FilterRooms", scope)).call(rhino, scope, scope, new Object[]{null});
roomarray = getArray((NativeArray)scope.get("roomarray", scope));
((Function)scope.get("FilterRoomsByDept", scope)).call(rhino, scope, scope, new Object[]{null});
roombydeptarray = getArray((NativeArray)scope.get("roombydeptarray", scope));
((Function)scope.get("FilterProgrammesByCode", scope)).call(rhino, scope, scope, new Object[]{null});
progarrayByCode = getArray((NativeArray)scope.get("progarray", scope));
((Function)scope.get("FilterProgrammesByTitle", scope)).call(rhino, scope, scope, new Object[]{null});
progarrayByTitle = getArray((NativeArray)scope.get("progarray", scope));
((Function)scope.get("FilterStaff", scope)).call(rhino, scope, scope, new Object[]{null});
staffarray = getArray((NativeArray)scope.get("staffarray", scope));
printArray(deptarray, "deptarray");
printArray(zonearray, "zonearray");
printArray(modulearrayByCode, "modulearrayByCode");
printArray(modulearrayByTitle, "modulearrayByTitle");
printArray(studsetarrayByCode, "studsetarrayByCode");
printArray(studsetarrayByTitle, "studsetarrayByTitle");
printArray(roomarray, "roomarray");
printArray(roombydeptarray, "roombydeptarray");
printArray(progarrayByCode, "progarrayByCode");
printArray(progarrayByTitle, "progarrayByTitle");
printArray(staffarray, "staffarray");
Context.exit();
}
private void printArray(String[][] array, String tag){
String output = "";
for(int row=0;row<array.length;row++){
for(int column=0;column<array[row].length;column++){
output+=array[row][column]+"\n";
}
}
Log.e( (tag==null?"JavaArray":tag),output);
}
private String[][] getArray(NativeArray nativeArray){
String[][] javaArray = new String[nativeArray.size()][((NativeArray)nativeArray.get(0)).size()];
for (Integer row : nativeArray.getIndexIds()) {
for(int column=0;column<((NativeArray)nativeArray.get(row)).size();column++){
javaArray[row][column] = (String)((NativeArray) nativeArray.get(row)).get(column);
}
}
return javaArray;
}
}
}