I am trying to display array data using JSON Volley in PostsBasedOnCategory.java. Array data that I want to display are, Title post, and excerpt based on specific category from https://www.kisahmuslim.com/wp-json/wp/v2/categories. But unfortunately, it only showing one result.
Below you can check my code
DaftarCategories.java
public class CallingPage extends AsyncTask<String, String, String> {
HttpURLConnection conn;
java.net.URL url = null;
private int page = 1;
#Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
showNoFav(false);
pb.setVisibility(View.VISIBLE);
}
#Override
protected String doInBackground(String... params) {
try {
url = new URL("https://www.kisahmuslim.com/wp-json/wp/v2/categories");
}
catch(MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return e.toString();
}
try {
// Setup HttpURLConnection class to send and receive data from php and mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("GET");
// setDoOutput to true as we recieve data from json file
conn.setDoOutput(true);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return e1.toString();
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Pass data to onPostExecute method
return (result.toString());
} else {
return("koneksi gagal");
}
} catch (IOException e) {
e.printStackTrace();
return e.toString();
} finally {
conn.disconnect();
}
}
protected void onPostExecute(String result)
{
JsonArrayRequest stringRequest = new JsonArrayRequest(Request.Method.GET, SumberPosts.HOST_URL+"wp/v2/categories/", null, new Response.Listener<JSONArray>()
{
#Override
public void onResponse(JSONArray response) {
// display response
Log.d(TAG, response.toString() + "Size: "+response.length());
// agar setiap kali direfresh data tidak redundant
typeForPosts.clear();
for(int i=0; i<response.length(); i++) { //ambil semua objek yang ada
final CategoriesModel post = new CategoriesModel();
try {
Log.d(TAG, "Object at " + i + response.get(i));
JSONObject obj = response.getJSONObject(i);
post.setId(obj.getInt("id"));
post.setPostURL(obj.getString("link"));
//Get category name
post.setCategory(obj.getString("name"));
//////////////////////////////////////////////////////////////////////////////////////
// getting article konten
JSONObject postCategoryParent = obj.getJSONObject("_links");
JSONArray postCategoryObj = postCategoryParent.getJSONArray("wp:post_type");
JSONObject postCategoryIndex = postCategoryObj.getJSONObject(0); //ambil satu objek saja
String postCategoryUrl = postCategoryIndex.getString("href"); //satu objek yang dimaksud adalah href
if(postCategoryUrl != null) {
Log.d(TAG, postCategoryIndex.getString("href"));
JsonArrayRequest getKonten = new JsonArrayRequest(Request.Method.GET, postCategoryUrl, null, new Response.Listener<JSONArray>()
{
#Override
public void onResponse(JSONArray respon) {
Log.d(TAG, respon.toString() + "Size: "+respon.length());
for(int d=0; d<respon.length(); d++) {
try {
//Log.d(TAG, "Object at " + i + respon.get());
JSONObject objek = respon.getJSONObject(d); //ambil semua artikel yang tersedia di postCategoryUrl
post.setId(objek.getInt("id"));
post.setCreatedAt(objek.getString("date"));
post.setPostURL(objek.getString("link"));
//Get category title
JSONObject titleObj = objek.getJSONObject("title");
post.setJudul(titleObj.getString("rendered"));
//Get excerpt
JSONObject exerptObj = objek.getJSONObject("excerpt");
post.setExcerpt(exerptObj.getString("rendered"));
// Get content
JSONObject contentObj = objek.getJSONObject("content");
post.setContent(contentObj.getString("rendered"));
}
catch (JSONException e) {
e.printStackTrace();
}
}// for category
} //onResponse2
}, new Response.ErrorListener() { //getKonten
#Override
public void onErrorResponse(VolleyError error) {
pb.setVisibility(View.GONE);
Log.d(TAG, error.toString());
}
});
queue.add(getKonten);
} //if postCategoryUrl
//////////////////////////////////////////////////////////////////////////////////////
typeForPosts.add(post);
} //try 1
catch (JSONException e) {
e.printStackTrace();
}
} //for 1
pb.setVisibility(View.GONE);
recycleViewWordPress.setAdapter(mAdapter);
mAdapter.notifyDataSetChanged();
} //onResponse1
}, new Response.ErrorListener() { //stringRequest
#Override
public void onErrorResponse(VolleyError error) {
showNoFav(true);
pb.setVisibility(View.GONE);
Log.e(TAG, "Error: " + error.getMessage());
Toast.makeText(getContext(), "Tidak bisa menampilkan data. Periksa kembali sambungan internet Anda", Toast.LENGTH_LONG).show();
}
});
// Add the request to the RequestQueue.
queue.add(stringRequest);
} //onPostExecute
} //CallingPage
#Override
public void onPostingSelected(int pos) {
CategoriesModel click = typeForPosts.get(pos);
excerpt = click.getExcerpt();
//gambar = click.getPostImg();
judul = click.getJudul();
//url = click.getPostURL();
content = click.getContent();
Bundle bundle = new Bundle();
bundle.putString("judul", judul);
//bundle.putString("gambar", gambar);
//bundle.putString("url", url);
bundle.putString("content", content);
bundle.putString("excerpt", excerpt);
PostsBasedOnCategory bookFragment = new PostsBasedOnCategory();
bookFragment.setArguments(bundle);
AppCompatActivity activity = (AppCompatActivity) getContext();
activity.getSupportFragmentManager().beginTransaction().replace(R.id.flContainerFragment, bookFragment).addToBackStack(null).commit();
}
PostsBasedOnCategory.java
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.activity_wordpress, container,false);
ButterKnife.bind(this,view);
setHasOptionsMenu(true);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
swipeRefreshLayout =(SwipeRefreshLayout) getActivity().findViewById(R.id.swipeRefreshLayout);
recycleViewWordPress =(RecyclerView) getActivity().findViewById(R.id.recycleViewWordPress);
pb = (ProgressBar) getActivity().findViewById(R.id.loadingPanel);
noFavtsTV = getActivity().findViewById(R.id.no_favt_text);
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
swipeRefreshLayout.setRefreshing(false);
pb.setVisibility(View.VISIBLE);
recycleViewWordPress.setAdapter(mAdapter);
}
});
typeForPosts = new ArrayList<CategoriesModel>();
recycleViewWordPress.setHasFixedSize(true);
recycleViewWordPress.setLayoutManager(new LinearLayoutManager(getContext()));
recycleViewWordPress.setNestedScrollingEnabled(false);
mAdapter = new AdapterCategoryPosts(getContext(), typeForPosts, this);
recycleViewWordPress.setAdapter(mAdapter);
mAdapter.notifyDataSetChanged();
loadData();
}
public void loadData() {
Bundle bundel = this.getArguments();
long id = bundel.getLong("id");
String kategori = bundel.getString("kategori");
String title = bundel.getString("judul");
String excerpt = bundel.getString("excerpt");
String pict = bundel.getString("gambar");
String url = bundel.getString("url");
String konten = bundel.getString("konten");
CategoriesModel list = new CategoriesModel();
list.setId(id);
list.setCategory(kategori);
list.setJudul(title);
list.setExcerpt(excerpt);
list.setPostImg(pict);
list.setPostURL(url);
list.setContent(konten);
typeForPosts.add(list);
}
Logcat
2019-09-07 12:01:27.941 11246-11246/com.kursusarabic.arabicforfun D/postFrag: [{"id":12,"count":53,"description":"","link":"https:\/\/kisahmuslim.com\/category\/kisah-nyata\/biografi-ulama","name":"Biografi Ulama","slug":"biografi-ulama","taxonomy":"category","parent":29,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/12"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"up":[{"embeddable":true,"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/29"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=12"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}},{"id":26,"count":8,"description":"","link":"https:\/\/kisahmuslim.com\/category\/download","name":"Download","slug":"download","taxonomy":"category","parent":0,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/26"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=26"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}},{"id":1812,"count":9,"description":"","link":"https:\/\/kisahmuslim.com\/category\/info","name":"Info","slug":"info","taxonomy":"category","parent":0,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/1812"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=1812"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}},{"id":17,"count":3,"description":"","link":"https:\/\/kisahmuslim.com\/category\/kisah-nyata\/kisah-birrul-walidain","name":"Kisah Birrul Walidain","slug":"kisah-birrul-walidain","taxonomy":"category","parent":29,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/17"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"up":[{"embeddable":true,"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/29"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=17"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}},{"id":25,"count":31,"description":"","link":"https:\/\/kisahmuslim.com\/category\/kisah-nyata\/kisah-hidayah-islam","name":"Kisah Hidayah Islam","slug":"kisah-hidayah-islam","taxonomy":"category","parent":29,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/25"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"up":[{"embeddable":true,"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/29"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=25"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}},{"id":16,"count":49,"description":"","link":"https:\/\/kisahmuslim.com\/category\/kisah-nyata\/kisah-kaum-durhaka","name":"Kisah Kaum Durhaka","slug":"kisah-kaum-durhaka","taxonomy":"category","parent":29,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/16"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"up":[{"embeddable":true,"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/29"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=1
2019-09-07 12:01:27.942 11246-11246/com.kursusarabic.arabicforfun D/postFrag: Object at 0{"id":12,"count":53,"description":"","link":"https:\/\/kisahmuslim.com\/category\/kisah-nyata\/biografi-ulama","name":"Biografi Ulama","slug":"biografi-ulama","taxonomy":"category","parent":29,"meta":[],"_links":{"self":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/12"}],"collection":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/taxonomies\/category"}],"up":[{"embeddable":true,"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/categories\/29"}],"wp:post_type":[{"href":"https:\/\/kisahmuslim.com\/wp-json\/wp\/v2\/posts?categories=12"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
2019-09-07 12:01:27.942 11246-11246/com.kursusarabic.arabicforfun D/postFrag: https://kisahmuslim.com/wp-json/wp/v2/posts?categories=12
You cannot call network requests in loop, Use async processing or
Retrofit & RxJava multiple requests complete
and after updating typeForPosts, there is no need to setAdapter on recyclerview just call adapter.notifyDataSetChanged()
For some reason my jdbctemplate is not picking up the info in my application.properties file. I can only insert in my db when I make my own connection exposing my username and password in the file. Why isn't spring boot picking this up? Please help!
I am calling the addTaglocation mode while I am still reading tags from multiple RFID readers. Would this cause the issue? If so how do I solve it. Thanks in advance.
I start reading the tag from multiple rfid readers from a controller.
Full class where I am calling the create method (addTaglocation method):
public class TagInventory extends AlienClass1Reader implements
MessageListener, TagTableListener{
private final int MAX_THREAD = 50;
private Thread[] m_run_process = new Thread[MAX_THREAD];
private AlienReader[] m_inventory = new AlienReader[MAX_THREAD];
public boolean stopInventory = false;
ReaderProfileService rps;
VehicleService vs;
private boolean ThreadStop = true;
private int lastThreadId = -1;
private MessageListenerService service;
private TagTable tagTable = new TagTable();
private TagTableListener tagTableListener;
private static final Logger log =LogManager.getLogger(TagInventory.class);
#Autowired
TaglocationDAOJdbc taglocationDAOJdbc;
public TagInventory() throws AlienReaderException, IOException{
Start();
}
public void stopTag() throws AlienReaderException{
Stop();
}
private void Stop() throws AlienReaderException{
ThreadStop = true;
for (lastThreadId=0; lastThreadId < Reader.ipAddress.length;
lastThreadId++){
if(m_inventory[lastThreadId] != null){
m_inventory[lastThreadId].stopInventory = true;
service.stopService();
try{
Thread.sleep(200);
}catch(Exception e){
e.getMessage();
}
//m_inventory[lastThreadId].close();
m_inventory[lastThreadId].open();
m_inventory[lastThreadId].autoModeReset();
m_inventory[lastThreadId].setAutoMode(AlienClass1Reader.OFF);
m_inventory[lastThreadId].setNotifyMode(AlienClass1Reader.OFF);
m_inventory[lastThreadId].close();
}
}
}
private void Start() throws AlienReaderException, IOException{
ThreadStop = false;
service= new MessageListenerService(3900);
service.setMessageListener(this);
service.startService();
for (lastThreadId = 0; lastThreadId < Reader.ipAddress.length; lastThreadId++)
{
m_inventory[lastThreadId] = new AlienReader(Reader.ipAddress[lastThreadId], Reader.port, Reader.username[lastThreadId], Reader.password[lastThreadId]);
log.info("taginventory reader: "+ Reader.ipAddress[lastThreadId]+"Thread: "+lastThreadId);
m_run_process[lastThreadId] = new Thread(new StartInventoryThread(Reader.ipAddress[lastThreadId], Reader.port, Reader.username[lastThreadId], Reader.password[lastThreadId], m_inventory[lastThreadId]));
m_run_process[lastThreadId].start();
}
--lastThreadId;
try
{
Thread.sleep(1000);
}
catch (Exception ex)
{
ex.getMessage();
}
}
class StartInventoryThread implements Runnable{
private String ip;
private int port;
private String user;
private String pwd;
private AlienReader ar;
StartInventoryThread(String ip, int port, String user, String pwd, AlienReader ar){
this.ip=ip;
this.port=port;
this.user=user;
this.pwd=pwd;
this.ar=ar;
}
#Override
public void run() {
try {
while(!stopInventory){
startRead(ip,port,user,pwd);
}
} catch (AlienReaderException | InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
#Override
public void tagAdded(Tag tag) {
log.info("NEW TAG: " + tag.getTagID()+ " LAST SEEN DATE: "+ tag.getRenewTime());
}
#Override
public void tagRemoved(Tag tag) {
// TODO Auto-generated method stub
}
#Override
public void tagRenewed(Tag tag) {
// TODO Auto-generated method stub
}
#Override
public synchronized void messageReceived(Message msg) {
if(msg instanceof ErrorMessage){
// log.info("Notify error from " + msg.getReaderIPAddress());
}else if (msg.getTagCount() == 0){
log.info("No tags!");
}else{
//log.info("Message received from: "+msg.getReaderIPAddress());
Tag[] tagL=msg.getTagList();
//String[] tagLString=new String[tagL.length];
for (int i=0;i<msg.getTagCount(); i++){
Tag tag = msg.getTag(i);
//System.out.println("Tag ID: "+tag.getTagID()+ " Last Seen: "+tag.getRenewTime());
this.tagTable.addTag(tag);
// log.info("Tag ID: "+tag.getTagID()+ " Last Seen: "+tag.getRenewTime()+ " Receive Antenna: "+tag.getReceiveAntenna());
//System.out.println("Tag: "+tag+ " Last Seen: "+tag.getRenewTime());
}
}
//check readerprofile
try {
updateLocation(Reader.ipAddress[this.lastThreadId]);
this.tagTable.removeOldTags();
} catch (NoReaderInfoException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoVehicleException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void addTaglocation(Taglocation tl){
Taglocation newtagloca= new Taglocation(tl.getReadername(),tl.getRfidtag(),tl.getZone(), tl.getTaggingsource(), tl.getVineight(), tl.getZonedate());
taglocationDAOJdbc.addtaglocation(newtagloca);
log.info("ADDED TAGG INFO!");
}
public void updateLocation(String read) throws NoReaderInfoException, NoVehicleException{
//update location of vehicle when tag read by readers
log.info("IN UPDATE LOCATION with reader: "+read);
Tag[] temp;
temp=this.tagTable.getTagList();
for (int i = 0; i < temp.length; i++) {
log.info("get taglist");
Tag tag = temp[i];
String rfid=tag.getTagID();
Timestamp newDate=new Timestamp(Calendar.getInstance().getTime().getTime());
Taglocation tl=new Taglocation(read, rfid, read, "", "vineight", newDate);
addTaglocation(tl);
}
}
public void startRead(String ip, int port, String user, String password) throws AlienReaderException, InterruptedException, UnknownHostException{
String myIP=InetAddress.getLocalHost().getHostAddress();
System.out.println("ip"+ ip);
AlienReader ar= new AlienReader(ip, port, user, password);
ar.open();
log.info("Reader" + ar.getIPAddress());
ar.setNotifyAddress(myIP, 3900);
ar.setNotifyFormat(AlienClass1Reader.TEXT_FORMAT);
ar.setNotifyTrigger("TrueFalse");
ar.setNotifyMode(AlienClass1Reader.ON);
ar.autoModeReset();
ar.setAutoStopTimer(5000); // Read for 5 seconds
ar.setAutoMode(AlienClass1Reader.ON);
tagTable.setTagTableListener(tagTableListener);
tagTable.setPersistTime(5000);
//tagTable.setPersistTime(1800000);
ar.close();
long runTime = 10000; // milliseconds
long startTime = System.currentTimeMillis();
do {
Thread.sleep(1000);
} while(service.isRunning()
&& (System.currentTimeMillis()-startTime) < runTime);
// Reconnect to the reader and turn off AutoMode and TagStreamMode.
log.info("\nResetting Reader");
ar.open();
ar.autoModeReset();
ar.setNotifyMode(AlienClass1Reader.OFF);
ar.close();
}
}
(UPDATED)
Application.properties file:
spring.datasource.url=jdbc:mysql://localhost:3306/DB
spring.datasource.username=
spring.datasource.password=
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
(UPDATED)
taglocationJDBCTemplate file
#Repository
public class TaglocationJDBCTemplate implements TaglocationDAO {
#Autowired
JdbcTemplate jdbcTemplate;
public void create(Taglocation tl){
KeyHolder keyHolder = new GeneratedKeyHolder();
jdbcTemplate.update(new PreparedStatementCreator(){
public PreparedStatement createPreparedStatement(final Connection connection) throws SQLException {
PreparedStatement ps = connection.prepareStatement("INSERT INTO TAGLOCATION (READERNAME, RFIDTAG, TAGGINGSOURCE, ZONE, VINEIGHT, ZONEDATE) VALUES (?,?,?,?,?,?)",
Statement.RETURN_GENERATED_KEYS);
ps.setString(1, tl.getReadername());
ps.setString(2,tl.getRfidtag());
ps.setString(3, tl.getTaggingsource());
ps.setString(4, tl.getZone());
ps.setString(5, tl.getVineight());
ps.setTimestamp(6, new Timestamp(System.currentTimeMillis()));
return ps;
}
}, keyHolder);
return (Integer) keyHolder.getKey();
}
controller file:
#RestController
public class TagInventoryController {
#Autowired
TagService tagService;
#RequestMapping("/runTasks")
public String tagRead(){
tagService.startTagRead();
return "Readers are activated.";
}
}
I am new to spark streaming. I want to stream a url online in order to retrieve info from a certain URL, I used the JavaCustomReceiver in order to stream a url.
This is the code I'm using (source)
public class JavaCustomReceiver extends Receiver<String> {
private static final Pattern SPACE = Pattern.compile(" ");
public static void main(String[] args) throws Exception {
SparkConf sparkConf = new SparkConf().setAppName("JavaCustomReceiver");
JavaStreamingContext ssc = new JavaStreamingContext(sparkConf, new Duration(1000));
JavaReceiverInputDStream<String> lines = ssc.receiverStream(
new JavaCustomReceiver("http://stream.meetup.com/2/rsvps", 80));
JavaDStream<String> words = lines.flatMap(new
FlatMapFunction<String, String>() {
#Override
public Iterator<String> call(String x) {
return Arrays.asList(SPACE.split(x)).iterator();
}
});
JavaPairDStream<String, Integer> wordCounts = words.mapToPair(
new PairFunction<String, String, Integer>() {
#Override
public Tuple2<String, Integer> call(String s) {
return new Tuple2<>(s, 1);
}
}).reduceByKey(new Function2<Integer, Integer, Integer>() {
#Override
public Integer call(Integer i1, Integer i2) {
return i1 + i2;
}
});
wordCounts.print();
ssc.start();
ssc.awaitTermination();
}
String host = null;
int port = -1;
public JavaCustomReceiver(String host_, int port_) {
super(StorageLevel.MEMORY_AND_DISK_2());
host = host_;
port = port_;
}
public void onStart() {
new Thread() {
#Override
public void run() {
receive();
}
}.start();
}
public void onStop() {
}
private void receive() {
try {
Socket socket = null;
BufferedReader reader = null;
String userInput = null;
try {
// connect to the server
socket = new Socket(host, port);
reader = new BufferedReader(
new InputStreamReader(socket.getInputStream(), StandardCharsets.UTF_8));
// Until stopped or connection broken continue reading
while (!isStopped() && (userInput = reader.readLine()) != null) {
System.out.println("Received data '" + userInput + "'");
store(userInput);
}
} finally {
Closeables.close(reader, /* swallowIOException = */ true);
Closeables.close(socket, /* swallowIOException = */ true);
}
restart("Trying to connect again");
} catch (ConnectException ce) {
// restart if could not connect to server
restart("Could not connect", ce);
} catch (Throwable t) {
restart("Error receiving data", t);
}
}
}
However, I keep getting a java.net.UnknownHostException
How can I fix this? What is wrong with the code that I'm using ?
After reading the code of the custom receiver referenced, it is clear that it is a TCP receiver that connects to a host:port and not an HTTP receiver that could take an URL. You'll have to change the code to read from an HTTP endpoint.
I am trying to run a simple Android Thing project that simply captures and renders the captured image in the display. I took the sample code from (https://github.com/googlecodelabs/androidthings-imageclassifier/tree/master/imageclassifier-add-camera) without the image recognition part. But I'm getting the following error-
I/InstantRun: starting instant run server: is main process
I/CameraManagerGlobal: Connecting to camera service
D/CameraHandler: Using camera id 0
W/CameraHandler: Cannot capture image. Camera not initialized.
D/CameraHandler: Opened camera.
So it seems it detects the camera but it can't capture images from the camera. Anyone faced similar issues on AndroidThings platform?
Main Camera Handler code provided below-
public class CameraHandler {
private static final String TAG = CameraHandler.class.getSimpleName();
public static final int IMAGE_WIDTH = 320;
public static final int IMAGE_HEIGHT = 240;
private static final int MAX_IMAGES = 1;
private CameraDevice mCameraDevice;
private CameraCaptureSession mCaptureSession;
/**
* An {#link android.media.ImageReader} that handles still image capture.
*/
private ImageReader mImageReader;
// Lazy-loaded singleton, so only one instance of the camera is created.
private CameraHandler() {
}
private static class InstanceHolder {
private static CameraHandler mCamera = new CameraHandler();
}
public static CameraHandler getInstance() {
return InstanceHolder.mCamera;
}
/**
* Initialize the camera device
*/
public void initializeCamera(Context context,
Handler backgroundHandler,
ImageReader.OnImageAvailableListener imageAvailableListener) {
// Discover the camera instance
CameraManager manager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
String[] camIds = {};
try {
camIds = manager.getCameraIdList();
} catch (CameraAccessException e) {
Log.d(TAG, "Cam access exception getting IDs", e);
}
if (camIds.length < 1) {
Log.d(TAG, "No cameras found");
return;
}
String id = camIds[0];
Log.d(TAG, "Using camera id " + id);
// Initialize the image processor
mImageReader = ImageReader.newInstance(IMAGE_WIDTH, IMAGE_HEIGHT,
ImageFormat.JPEG, MAX_IMAGES);
mImageReader.setOnImageAvailableListener(
imageAvailableListener, backgroundHandler);
// Open the camera resource
try {
manager.openCamera(id, mStateCallback, backgroundHandler);
} catch (CameraAccessException cae) {
Log.d(TAG, "Camera access exception", cae);
}
}
/**
* Callback handling device state changes
*/
private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() {
#Override
public void onOpened(#NonNull CameraDevice cameraDevice) {
Log.d(TAG, "Opened camera.");
mCameraDevice = cameraDevice;
}
#Override
public void onDisconnected(#NonNull CameraDevice cameraDevice) {
Log.d(TAG, "Camera disconnected, closing.");
closeCaptureSession();
cameraDevice.close();
}
#Override
public void onError(#NonNull CameraDevice cameraDevice, int i) {
Log.d(TAG, "Camera device error, closing.");
closeCaptureSession();
cameraDevice.close();
}
#Override
public void onClosed(#NonNull CameraDevice cameraDevice) {
Log.d(TAG, "Closed camera, releasing");
mCameraDevice = null;
}
};
/**
* Begin a still image capture
*/
public void takePicture() {
if (mCameraDevice == null) {
Log.w(TAG, "Cannot capture image. Camera not initialized.");
return;
}
// Here, we create a CameraCaptureSession for capturing still images.
try {
mCameraDevice.createCaptureSession(
Collections.singletonList(mImageReader.getSurface()),
mSessionCallback,
null);
} catch (CameraAccessException cae) {
Log.d(TAG, "access exception while preparing pic", cae);
}
}
/**
* Callback handling session state changes
*/
private CameraCaptureSession.StateCallback mSessionCallback =
new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(#NonNull CameraCaptureSession cameraCaptureSession) {
// The camera is already closed
if (mCameraDevice == null) {
return;
}
// When the session is ready, we start capture.
mCaptureSession = cameraCaptureSession;
triggerImageCapture();
}
#Override
public void onConfigureFailed(#NonNull CameraCaptureSession cameraCaptureSession) {
Log.w(TAG, "Failed to configure camera");
}
};
/**
* Execute a new capture request within the active session
*/
private void triggerImageCapture() {
try {
final CaptureRequest.Builder captureBuilder =
mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(mImageReader.getSurface());
captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON);
//captureBuilder.set(CaptureRequest.CONTROL_AWB_MODE, CaptureRequest.CONTROL_AWB_MODE_AUTO);
Log.d(TAG, "Capture request created.");
mCaptureSession.capture(captureBuilder.build(), mCaptureCallback, null);
} catch (CameraAccessException cae) {
Log.d(TAG, "camera capture exception");
}
}
/**
* Callback handling capture session events
*/
private final CameraCaptureSession.CaptureCallback mCaptureCallback =
new CameraCaptureSession.CaptureCallback() {
#Override
public void onCaptureProgressed(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull CaptureResult partialResult) {
Log.d(TAG, "Partial result");
}
#Override
public void onCaptureCompleted(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull TotalCaptureResult result) {
session.close();
mCaptureSession = null;
Log.d(TAG, "CaptureSession closed");
}
};
private void closeCaptureSession() {
if (mCaptureSession != null) {
try {
mCaptureSession.close();
} catch (Exception ex) {
Log.e(TAG, "Could not close capture session", ex);
}
mCaptureSession = null;
}
}
/**
* Close the camera resources
*/
public void shutDown() {
closeCaptureSession();
if (mCameraDevice != null) {
mCameraDevice.close();
}
}
}
The pitfall with camera:
Check the permissions in Manifest file, and restart the device.
The camera-permission is granted not after installing the application, but first after install and RESTART of device.
see https://developer.android.com/things/sdk/index.html
I have 2 classes one called Gui and one called Listener.
The code for Listener is :
package app.assignment.u0961036.core;
import net.jini.space.JavaSpace;
public class Listener extends Thread {
private JavaSpace space;
private Gui list;
public void run() {
space = SpaceUtils.getSpace("localhost");
System.out.println("In Listener");
int i = 0;
while(true){
i++;
try{
Message mTemplate = new Message();
System.out.println("Listner: template created");
Message nextMessage = (Message)space.take(mTemplate,null,Long.MAX_VALUE);
System.out.println("Listner: Message created");
String message = nextMessage.message;
System.out.println("Listner: message= "+message);
list.newMessage(message);
} catch ( Exception e) {
e.printStackTrace();
}
if(i % 10 == 0){
System.out.println("I = "+i);
}
}
}
public static void listen() {
(new Listener()).start();
}
The relevant code in Gui is:
public void newMessage(String message){
System.out.println("in new message");
chatTextArea.append(" Someone Says: " + message + "\n" );
}
When The code in Listener is run I get a null pointer from the following line:
list.newMessage(message);
I'm not sure why because the object is created.
The GUI is also created win the Gui class if you haven't already guessed.
any Ideas?
package app.assignment.u0961036.core;
import net.jini.space.JavaSpace;
public class Listener extends Thread {
private JavaSpace space;
space = new JavaSpace();
private Gui list;
list = new Gui();
public void run() {
space = SpaceUtils.getSpace("localhost");
System.out.println("In Listener");
int i = 0;
while(true){
i++;
try{
Message mTemplate = new Message();
System.out.println("Listner: template created");
Message nextMessage = (Message)space.take(mTemplate,null,Long.MAX_VALUE);
System.out.println("Listner: Message created");
String message = nextMessage.message;
System.out.println("Listner: message= "+message);
list.newMessage(message);
} catch ( Exception e) {
e.printStackTrace();
}
if(i % 10 == 0){
System.out.println("I = "+i);
}
}
}
public static void listen() {
(new Listener()).start();
}
The code above should fix your problem I think. In Java you create Objects by declaring and instantiating and initialising them. Read here for more information.