Develop Reference

How can I stop async tasks that loops in background android after onPause() is called?

I'm using package com.hierynomus.smbj.share; to connect via smb2 to a network location in order to check it's connectivity however this only runs at the start of my activity (in background).
I've added a listener to return after the task has returned a string value (fail, success) once the the listener in the activity (i called the task from) is called, I then create a new instance of the Connection Status (this loops it)
This is how i check for the connection at onCreate() of an activity
//Global ConnectionStatus connectionStatus;
connectionStatus = new ConnectionStatus();
connectionStatus.setContext(this);
connectionStatus.setListener(this);
connectionStatus.setCon(databaseReadWrite.getMydbc());
connectionStatus.execute("CheckDatabase", "nodelay");
This is how I'm trying to cancel task when another activity is opened
protected void onPause() {
delay.equals("cancel");
super.onPause();
MyApplication.activityPaused();
if (connectionStatus != null) {
connectionStatus.cancel(true);
}
hasRun = false;
}
Then this runs in the same activity after the async task is completed so i've re-run a new instance of connectionStatus
#Override
public void onTaskCompleted(String result) {
ActionBar actionBar = this.getSupportActionBar();
String title = getTitle().toString();
String code = handlingFunctions.getResultCode(result);
if (code.equals("1")) {
Message.message(this, " Database connected to server!");
setTitle(title + result);
} else if (code.equals("2")) {
actionBar.setBackgroundDrawable(new ColorDrawable(Color.RED));
alertDialog.message(this, result);
} else if (code.equals("0")) {
actionBar.setBackgroundDrawable(new ColorDrawable(Color.RED));
setTitle(title + " Database connected in offline mode");
alertDialog.message(this, result);
} else if (code.equals("3")) {
//alertDialog.message(this, result);
imageStatus.setText(result);
} else if (code.equals("4")) {
imageStatus.setText(result);
}
connectionStatus = new ConnectionStatus();
connectionStatus.setContext(getApplicationContext());
connectionStatus.setListener(AllParts.this);
connectionStatus.setCon(databaseReadWrite.getMydbc());
connectionStatus.execute("CheckDatabase", "delay");
}
}
public class ConnectionStatus extends AsyncTask<String, Void, String> {
private OnConnectionStatusComplete listener;
private ArrayList<String> imageNames;
private ArrayList<ImageDetails> currentImageDetails;
private SQLiteConnection sqLiteConnection;
private Context context;
public void setListener(OnConnectionStatusComplete listen) {
this.listener = listen;
}
public void setImageNames(ArrayList<String> ImageNames) {
this.imageNames = ImageNames;
}
public void setCurrentDetails(ArrayList<ImageDetails> details) {
this.currentImageDetails = details;
}
#Override
protected void onPostExecute(String s) {
listener.onTaskCompleted(s);
}
public void setContext(Context mContext) {
context = mContext;
}
public void setCon(SQLiteConnection sqlite) {
sqLiteConnection = sqlite;
}
#Override
protected String doInBackground(String... strings) {
if(this.isCancelled()){
return "";
}else{
MyApplication myApplication = (MyApplication) context.getApplicationContext();
String IPAddress = myApplication.getIpaddress();
String domain = myApplication.getDomainname();
String username = myApplication.getUsername();
String password = myApplication.getPassword();
String containingFolder = myApplication.getSharefolder();
String temp = "";
//return null;
if (strings[1].equals("delay")) {
try {
Thread.sleep(6000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
if (strings[0].equals("CheckDatabase")) {
temp = checkDatabaseConnect();
} else {
temp = checkImageConnection(IPAddress, domain, username, password, containingFolder);
}
return temp;
}
}
String checkDatabaseConnect() {
String statement = "PRAGMA sync_status";
JSONArray is_ready = new JSONArray();
try {
SQLiteStatement mystatement = null;
try {
mystatement = sqLiteConnection.prepareStatement(statement);
} catch (SQLException ex) {
try {
java.io.File path = new java.io.File("/sdcard/exports/logs");
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
String currentDateTime = dateFormat.format(new Date()) + " ";
java.io.File myFile = new java.io.File(path, "DBCrashes.txt");
FileOutputStream fOut = new FileOutputStream(myFile, true);
OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
myOutWriter.append("\n" +
"\r");
myOutWriter.append(currentDateTime + "Get pragma results: (" + statement + ")" + ex);
myOutWriter.close();
fOut.close();
} catch (java.io.IOException e) {
//do something if an IOException occurs.
}
}
mystatement.step();
int ncols = mystatement.getColumnCount();
if (ncols > 0) {
String result = mystatement.getColumnTextNativeString(0);
JSONObject jObject = new JSONObject(result);
is_ready = jObject.getJSONArray("peers");
if (is_ready.length() > 0) {
return "Success, Database is connected! (1)";
} else {
return "The database is not connected to the server. In offline mode, check network and restart application to connect to server. (0)";
}
}
mystatement.dispose();
} catch (SQLException ex) {
try {
java.io.File path = new java.io.File("/sdcard/exports/logs");
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
String currentDateTime = dateFormat.format(new Date()) + " ";
java.io.File myFile = new java.io.File(path, "DBCrashes.txt");
FileOutputStream fOut = new FileOutputStream(myFile, true);
OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
myOutWriter.append("\n" +
"\r");
myOutWriter.append(currentDateTime + " (" + statement + ")" + ex);
myOutWriter.close();
fOut.close();
return "No connection to a database, please try again (2)";
} catch (java.io.IOException e) {
//do something if an IOException occurs.
}
} catch (JSONException e) {
e.printStackTrace();
}
return "Success (5)";
}
}
The problem I'm having is after I leave the activity, the task is still running and returns this error (I know this because it takes into account the delay)

You do have implemented a handling for isCanceled but this implementation is only at the start.
Your current flow is like this:
task starts, immediately checks if it is cancelled or not (since it is the first line in doInBackground)
onPause is called, cancel of the task is invoked
since the cancel check has already been made your task continues to run freely
How do you solve this?
The easiest way would be to check if it is cancelled before checkDatabaseConnection or checkImageConnection is called. And even inside those methods check if it is cancelled or not.
Even if that is done correctly, your Thread.sleep could cause your AsyncTask being cancelled 6s after onPause is called.
For reasons like this, AsyncTask is not used anymore. There are other options for Threading which are much better.
This or this will give you a starting point.

try checking if the task is cancelled after the Thread.sleep(6000) , so even if the task was in sleep when cancel is called it will return when it is done.
if (strings[1].equals("delay")) {
try {
Thread.sleep(6000);
if(this.isCancelled()) {
return "";
}
} catch (InterruptedException e) {
e.printStackTrace();
}
/*if(this.isCancelled()) {
return "";
}*/
}

Call an AsyncTask subclass of activity from another class?

I know this kind of questions are maybe too old, but I got stock with this silly thing.
I have an AsyncTask class which is a subclass of an activity class, and right now I want to call it from another class: following codes shows what I mean:
public class STA extends Activity {
public class ListSpdFiles extends AsyncTask<Void, Void, String[]> {
private static final String TAG = "ListSpdFiles: ";
/**
* Status code returned by the SPD on operation success.
*/
private static final int SUCCESS = 4;
private String initiator;
private String path;
private SecureApp pcas;
private boolean isConnected = false; // connected to PCAS service?
private PcasConnection pcasConnection = new PcasConnection() {
#Override
public void onPcasServiceConnected() {
Log.d(TAG, "pcasServiceConnected");
latch.countDown();
}
#Override
public void onPcasServiceDisconnected() {
Log.d(TAG, "pcasServiceDisconnected");
}
};
private CountDownLatch latch = new CountDownLatch(1);
public ListSpdFiles(String initiator, String path) {
this.initiator = initiator;
this.path = path;
}
private void init() {
Log.d(TAG, "starting task");
pcas = new AndroidNode(getApplicationContext(), pcasConnection);
isConnected = pcas.connect();
}
private void term() {
Log.d(TAG, "terminating task");
if (pcas != null) {
pcas.disconnect();
pcas = null;
isConnected = false;
}
}
#Override
protected void onPreExecute() {
super.onPreExecute();
init();
}
#Override
protected String[] doInBackground(Void... params) {
// check if connected to PCAS Service
if (!isConnected) {
Log.v(TAG, "not connected, terminating task");
return null;
}
// wait until connection with SPD is up
try {
if (!latch.await(20, TimeUnit.SECONDS)) {
Log.v(TAG, "unable to connected within allotted time, terminating task");
return null;
}
} catch (InterruptedException e) {
Log.v(TAG, "interrupted while waiting for connection in lsdir task");
return null;
}
// perform operation (this is where the actual operation is called)
try {
return lsdir();
} catch (DeadServiceException e) {
Log.i(TAG, "service boom", e);
return null;
} catch (DeadDeviceException e) {
Log.i(TAG, "device boom", e);
return null;
}
}
#Override
protected void onPostExecute(String[] listOfFiles) {
super.onPostExecute(listOfFiles);
if (listOfFiles == null) {
Log.i(TAG, "task concluded with null list of files");
// tv.setText("task concluded with a null list of files");
} else {
Log.i(TAG, "task concluded with the following list of files: "
+ Arrays.toString(listOfFiles));
//tv.setText("List of files received is:\n" + Arrays.toString(listOfFiles));
}
term();
}
#Override
protected void onCancelled(String[] listOfFiles) {
super.onCancelled(listOfFiles);
Log.i(TAG, "lsdir was canceled");
term();
}
/**
* Returns an array of strings containing the files available at the given path, or
* {#code null} on failure.
*/
private String[] lsdir() throws DeadDeviceException, DeadServiceException {
Result<List<String>> result = pcas.lsdir(initiator, path); // the lsdir call to the
final Global globalVariable = (Global) getApplicationContext();
if (globalVariable.getPasswordButt() == false) {
// Calling Application class (see application tag in AndroidManifest.xml)
// Get name and email from global/application context
final boolean isusername = globalVariable.getIsUsername();
if (isusername == true) {
String username = "/" + getLastAccessedBrowserPage() + ".username" + ".txt";
//String password = "/" + CurrentURL + "password" + ".txt";
ByteArrayOutputStream baos = new ByteArrayOutputStream();
pcas.readFile(initiator, username, baos);
Log.i(TAG, "OutputStreampassword: "
+ new String(baos.toByteArray()));
String name = new String(baos.toByteArray());
if (!name.equalsIgnoreCase("")) {
globalVariable.setUsername(name);
// getCurrentInputConnection().setComposingText(name, 1);
// updateCandidates();
}
globalVariable.setIsUsername(false);
} else if (isusername == false)
Log.i(TAG, "Wrong Input Type For Username.");
// globalVariable.setUsernameButt(false);
} else if (globalVariable.getPasswordButt() == true) {
// Calling Application class (see application tag in AndroidManifest.xml)
// final Global globalVariable = (Global) getApplicationContext();
// Get name and email from global/application context
final boolean ispassword = globalVariable.getIsPassword();
if (ispassword == true) {
// String username = "/" + CurrentURL + "username" + ".txt";
String password = "/" + getLastAccessedBrowserPage() + ".password" + ".txt";
ByteArrayOutputStream baos = new ByteArrayOutputStream();
pcas.readFile(initiator, password, baos);
Log.i(TAG, "OutputStreampassword: "
+ new String(baos.toByteArray()));
String name = new String(baos.toByteArray());
if (!name.equalsIgnoreCase("")) {
globalVariable.setPassword(name);
//getCurrentInputConnection().setComposingText(name, 1);
// updateCandidates();
}
globalVariable.setIsPassword(false);
} else if (ispassword == false)
Log.i(TAG, "Wrong Input Type For Password.");
globalVariable.setPasswordButt(false);
// boolpassword=false;
}
//}
if (result.getState() != SUCCESS) {
Log.v(TAG, "operation failed");
return null;
}
if (result.getValue() == null) {
Log.v(TAG, "operation succeeded but operation returned null list");
return null;
}
return result.getValue().toArray(new String[0]);
}
}
public String getLastAccessedBrowserPage() {
String Domain = null;
Cursor webLinksCursor = getContentResolver().query(Browser.BOOKMARKS_URI, Browser.HISTORY_PROJECTION, null, null, Browser.BookmarkColumns.DATE + " DESC");
int row_count = webLinksCursor.getCount();
int title_column_index = webLinksCursor.getColumnIndexOrThrow(Browser.BookmarkColumns.TITLE);
int url_column_index = webLinksCursor.getColumnIndexOrThrow(Browser.BookmarkColumns.URL);
if ((title_column_index > -1) && (url_column_index > -1) && (row_count > 0)) {
webLinksCursor.moveToFirst();
while (webLinksCursor.isAfterLast() == false) {
if (webLinksCursor.getInt(Browser.HISTORY_PROJECTION_BOOKMARK_INDEX) != 1) {
if (!webLinksCursor.isNull(url_column_index)) {
Log.i("History", "Last page browsed " + webLinksCursor.getString(url_column_index));
try {
Domain = getDomainName(webLinksCursor.getString(url_column_index));
Log.i("Domain", "Last page browsed " + Domain);
return Domain;
} catch (URISyntaxException e) {
e.printStackTrace();
}
break;
}
}
webLinksCursor.moveToNext();
}
}
webLinksCursor.close();
return null;
}
public String getDomainName(String url) throws URISyntaxException {
URI uri = new URI(url);
String domain = uri.getHost();
return domain.startsWith("www.") ? domain.substring(4) : domain;
}}
Would you please tell me what should I do to fix this code?

Looking over the code I did not see anywhere you referenced anything from the Activity itself besides the application context so you can move the ListSpdFiles class to its own java file and pass it a context into the constructor when you make a new instance of it.
Put this class in a ListSpdFiles.java file so it is no longer an inner class.
public class ListSpdFiles extends AsyncTask<Void, Void, String[]> {
Context applicationContext;
public ListSpdFiles(Context context, String initiator, String path) {
this.initiator = initiator;
this.path = path;
applicationContext = context.getApplicationContext();
}
// The rest of your code still goes here. Replace other calls to
// getApplicationContext() with the new applicationContext field
}
You can now use this class anywhere a Context is available. You create a new instance by doing:
ListSpdFiles listSpdFilesTask = new ListSpdFiles(context, "someInitiator", "somePath");
listSpdFilesTask.execute();

Periodic LogCat polling for updates and saving to SDcard

Goal
Collect periodic updates of the LogCat and save (append) those chunks of text to a file on the SDcard
Problem
The Log class doesn't provide updates since a specific time-stamp
Possible solution
My plan is to periodically run code that is similar to: http://www.helloandroid.com/tutorials/reading-logs-programatically
or https://stackoverflow.com/a/9039352/550471
However, with one notable difference: use the -v time parameter to ensure that each line is time-stamped.
After each time the LogCat data is collected, the app will store the time-stamp of the last Log entry. The next time the LogCat data is collected the app will search through the text to find the time-stamp and then save the chunk of data to sdcard that was added to the Log since the specified time-stamp.
Possible problem
If the LogCat data is collected at too short periods then the CPU is busy processing a lot of 'old' data.
If the Logcat data is collected at too long periods then some data could be missed.
Is there a better way ?

This is what I came up with - it works very well when it doesn't freeze up.
As you might know, Runtime.getRuntime().exec("") has a pretty good chance of causing an ANR in Android earlier than Jelly Bean. If someone has a solution to overcome the ANR, then please share.
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import android.os.Environment;
import android.util.Log;
/*
* For (compressed) buffer sizes, see: http://elinux.org/Android_Logging_System
* buffer:main = 64KB
* buffer:radio = 64KB
* buffer:system = 64KB
* buffer:event = 256KB
*
* NOTE: the 'command' must include "-d -v time" !!
* to switch buffers, use "-b <buffer>"
*/
public class LogCatReader {
// constants
private static final String CR = "\r\n";
private static final String END_OF_DATE_TIME = "): ";
private static final int DEFAULT_SEARCH_START_INDEX = 0;
// member variables
private StringBuilder mLog;
private LogThread mLogThread = null;
private String mLastLogReadToken = "";
private String mLogCommand = "";
private int mStringCapacity;
private File mFileTarget = null;
// constructor
public LogCatReader(String command, int capacity) {
mLogCommand = command;
mStringCapacity = capacity;
}
// returns complete logcat buffer
// note: takes about 1.5sec to finish
synchronized public StringBuilder getLogComplete() {
try {
// capacity should be about 25% bigger than buffer size since the
// buffer is compressed
mLog = new StringBuilder(mStringCapacity);
// command to capture log
Process process = Runtime.getRuntime().exec(mLogCommand);
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
String line;
while ((line = bufferedReader.readLine()) != null) {
// append() is costly if capacity needs to be increased, be sure
// to reserve enough in the first place
mLog.append(line + CR);
}
} catch (IOException e) {
}
return mLog;
}
public String getLogUpdatesOnly() {
String strReturn = "";
StringBuilder sbLog = getLogComplete();
try {
int iStartindex = DEFAULT_SEARCH_START_INDEX;
// if there exists a token from a previous search then use that
if (mLastLogReadToken.length() > 0) {
iStartindex = sbLog.indexOf(mLastLogReadToken);
// if string not found then start at beginning
if (iStartindex == -1) {
// start search at beginning of log
iStartindex = DEFAULT_SEARCH_START_INDEX;
}
}
int iEndindex = sbLog.length();
// if token is found then move index to the next line
if (iStartindex > DEFAULT_SEARCH_START_INDEX) {
iStartindex = sbLog.indexOf(CR, iStartindex);
if (iStartindex != -1) {
iStartindex += CR.length();
} else {
// return an empty string
iStartindex = iEndindex;
}
}
// grab the data between the start and end indices
strReturn = sbLog.substring(iStartindex, iEndindex);
// grab date/time token for next search
iStartindex = sbLog.lastIndexOf(END_OF_DATE_TIME);
if (iStartindex != -1) {
iEndindex = iStartindex;
iStartindex = sbLog.lastIndexOf(CR, iEndindex);
iStartindex += CR.length();
if (iStartindex == -1) {
// read from beginning
iStartindex = 0;
}
mLastLogReadToken = sbLog.substring(iStartindex, iEndindex);
}
} catch (Exception e) {
strReturn = "";
}
return strReturn;
}
public void startPeriodicLogCatReader(int timePeriod, String logfilename) {
if (mLogThread == null) {
mLogThread = new LogThread(timePeriod, logfilename);
mLogThread.start();
}
}
public void stopPeriodicLogCatReader() {
if (mLogThread != null) {
mLogThread.interrupt();
mLogThread = null;
}
}
private class LogThread extends Thread {
private boolean mInterrupted;
private int mTimePeriod;// in seconds
private String mLogref;
private BufferedWriter mBuffWriter = null;
public boolean mPauseLogCollection = false;
// constructor: logfilename is optional - pass null to not use
public LogThread(int timePeriod, String logfilename) {
mTimePeriod = timePeriod;
if (logfilename != null) {
File fLogFolder = new File(
Environment.getExternalStorageDirectory() + "/logfiles");
if (fLogFolder.exists() == false) {
if (fLogFolder.mkdirs() == false) {
Log.e("LogCatReader",
"Could not create "
+ fLogFolder.getAbsolutePath());
}
}
mFileTarget = new File(
Environment.getExternalStorageDirectory() + "/logfiles",
logfilename);
if (mFileTarget.exists() == false) {
try {
// file doesn't yet exist - create a fresh one !
mFileTarget.createNewFile();
} catch (IOException e) {
e.printStackTrace();
mFileTarget = null;
}
}
}
}
#Override
public void interrupt() {
mInterrupted = true;
super.interrupt();
}
#Override
public void run() {
super.run();
// initialization
mInterrupted = false;
// set up storage
if (mFileTarget != null) {
try {
mBuffWriter = new BufferedWriter(new FileWriter(
mFileTarget, true), 10240);
} catch (IOException e) {
e.printStackTrace();
}
}
while ((mInterrupted == false) && (mBuffWriter != null)) {
if (mPauseLogCollection == false) {
// read log updates
mLogref = getLogUpdatesOnly();
// save log updates to file
try {
mBuffWriter.append(mLogref);
mBuffWriter.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
if (!mInterrupted) {
try {
sleep(mTimePeriod * 1000);
} catch (InterruptedException e) {
}
}
}
if (mBuffWriter != null) {
try {
mBuffWriter.close();
mBuffWriter = null;
} catch (IOException e) {
e.printStackTrace();
}
}
}
}// end of inner class
}// end of outer class
The procedure I used to find only the updates is to capture the date and time of the very last line of a logcat and use that as the search token next time around.
To use this class, the following is an example:
LogCatReader logcatPeriodicReader = new LogCatReader("logcat -b main -d -v time", 80 * 1024);//collect "main" buffer, exit after reading logcat
logcatPeriodicReader.startPeriodicLogReader(90, "log.txt");//read logcat every 90 secs

Having a bit of trouble tcp connecting in Android Client

This might be a complex problem with my application but I'll do my best to describe it as accurately as I can.
I am making an Android Client and making use of a couple of helper classes someone else handed to me at work. The helper Android classes are called TcpClient.java and PVDCAndroidClient.java. PVDCAndroidClient.java makes use out of the TcpCLient, using a tcpCLient object to connect via serverIP and port.
Here is PVDCAndroidClient.java:
public class PVDCAndroidClient {
// constants
public static final String DEFAULT_LOGIN_URI = "http://me.net:8000/";
private TcpClient tcpClient = null;
private UdpClient udpClient = null;
private boolean connected = false;
private boolean loggedin = false;
private static SimpleDateFormat sdf;
private String loginURI = DEFAULT_LOGIN_URI;
private int getUserNumber;
TcpMessageListener listener = null;
/**
* Connects to proxy server, blocks until complete or timeout
* #param serverIP
* #param port
*/
public void connect(String serverIP, int port)
{
try
{
if(serverIP.length() != 0 && port != 0)
{
tcpClient = new TcpClient();
tcpClient.addTcpListener(listener);
tcpClient.connect(serverIP, port);
}
}
catch(Exception e)
{
e.printStackTrace();
Log.d("Could not connect to server, possbile timeout...", "error");
}
}
///// Make login function a blocking call
// Default login, use last location as login location
public boolean login(String fName, String lName, String password)
{
return this.login(fName, lName, password, "last location");
}
public boolean login(String fName, String lName, String password, String region)
{
return this.login(fName, lName, password, "last location", 128, 128, 20);
}
public boolean login(String fName, String lName, String password, String region, int loginX, int loginY, int loginZ)
{ sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ", Locale.US);
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
// Check passed values
// x, y and z should be between [0, 256]
// strings should not be null or empty(except lName which can be empty)
if((loginX >= 0 && loginX <= 256) && (loginY >=0 && loginY <= 256) && (loginZ >= 0 && loginZ <= 256))
{
if(fName.length() != 0 && fName != null)
{
// Construct packet xml structure
// Send request and wait until reply or timeout
// return false if timeout (or throw exception?)
// if not timeout, read result packet and determine return value
// getUserNumber = tcpClient.getUserNum();
StringWriter stringWriter = new StringWriter();
XmlSerializer serializer = Xml.newSerializer();
try {
serializer.setOutput(stringWriter);
// Indentation is not required, but helps with reading
serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
// TODO: Remove hardcoding of strings, make either constants or place in strings.xml
// TODO: Move the header construction to other method as it is fairly constant other than request num and no need to repeat that much code
serializer.startTag("", "pvdc_pkt");
serializer.startTag("", "pvdc_header");
// TODO: replace this with a string unique to the system
serializer.startTag("", "ID");
serializer.text("838393djdjdjd");
serializer.endTag("", "ID");
// TODO: replace this with actual user number from server
serializer.startTag("", "user_num");
serializer.text("22");//get userNum from above
serializer.endTag("", "user_num");
// TODO: add a request number counter to increment this on each request
serializer.startTag("", "request_num");
serializer.text("1");
serializer.endTag("", "request_num");
serializer.startTag("", "DateTime");
serializer.text(sdf.toString()); //utc time variable.
serializer.endTag("", "DateTime");
serializer.endTag("", "pvdc_header");
serializer.startTag("", "pvdc_content");
serializer.attribute("", "type", "requestlogin");
serializer.startTag("", "name");
serializer.attribute("", "fname", fName);
serializer.attribute("", "lname", lName);
serializer.endTag("", "name");
serializer.startTag("", "password");
serializer.text(password);
serializer.endTag("", "password");
serializer.startTag("", "server");
serializer.text(this.loginURI);
serializer.endTag("", "server");
serializer.startTag("", "location");
serializer.attribute("", "region", region);
serializer.text(loginX + ";" + loginY +";" + loginZ);
serializer.endTag("", "location");
serializer.endTag("", "pvdc_content");
serializer.endTag("", "pvdc_pkt");
// Finish writing
serializer.endDocument();
// write xml data out
serializer.flush();
//
sendLogin(stringWriter);
} catch (Exception e) {
Log.e("Exception", "error occurred while creating xml file");
return false;
}
// Print out xml for debugging
Log.d("PVDCAndroidClient Login", stringWriter.toString().trim());
}
else
{
Log.d("Error in name checking", "fName either blank or null");
}
}
else
{
Log.d("login coordinates X,Y, or Z not between 0-256", "Coordinates Error");
}
return true;
}
// moveString should contain the properly formatted movement command(s)[see above move request description]
public void sendLogin(StringWriter stringWriter)
{
tcpClient.sendMessage(stringWriter.toString());
}
}
Here is the actual TcpClient.java:
public class TcpClient {
public interface TcpMessageListener{
public void onMessage(TcpClient client, String message);
}
private Socket socket = null;
private PrintWriter out = null;
private BufferedReader in = null;
private Thread listenThread = null;
private boolean listening = false;
private int userNum = -1;
private List<TcpMessageListener> listeners = new ArrayList<TcpMessageListener>();
public int getUserNum()
{
return this.userNum;
}
public TcpClient() {
}
public void addTcpListener(TcpMessageListener listener)
{
synchronized(this.listeners)
{
this.listeners.add(listener);
}
}
public void removeTcpListener(TcpMessageListener listener)
{
synchronized(this.listeners)
{
this.listeners.remove(listener);
}
}
public boolean connect(String serverIpOrHost, int port) {
try {
socket = new Socket(serverIpOrHost, port);
out = new PrintWriter(socket.getOutputStream(), true);
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
this.listenThread = new Thread(new Runnable(){
public void run() {
int charsRead = 0;
char[] buff = new char[4096];
while(listening && charsRead >= 0)
{
try {
charsRead = in.read(buff);
if(charsRead > 0)
{
Log.d("TCPClient",new String(buff).trim());
String input = new String(buff).trim();
synchronized(listeners)
{
for(TcpMessageListener l : listeners){
l.onMessage(TcpClient.this, input);
}
}
if (input.toLowerCase().contains("<user_num>")){
int index = input.toLowerCase().indexOf("<user_num>");
index += "<user_num>".length();
int index2 = input.toLowerCase().indexOf("</user_num>");
userNum = Integer.parseInt(input.substring(index, index2));
}
}
} catch (IOException e) {
Log.e("TCPClient", "IOException while reading input stream");
listening = false;
}
}
}
});
this.listening = true;
this.listenThread.setDaemon(true);
this.listenThread.start();
} catch (UnknownHostException e) {
System.err.println("Don't know about host");
return false;
} catch (IOException e) {
System.err.println("Couldn't get I/O for the connection");
return false;
} catch (Exception e) {
System.err.println(e.getMessage().toString());
return false;
}
return true;
}
public void sendMessage(String msg) {
if(out != null)
{
out.println(msg);
out.flush();
}
}
public void disconnect() {
try {
if(out != null){
out.close();
out = null;
}
if(in != null){
in.close();
in = null;
}
if (socket != null) {
socket.close();
socket = null;
}
if(this.listenThread != null){
this.listening = false;
this.listenThread.interrupt();
}
this.userNum = -1;
} catch (IOException ioe) {
System.err.println("I/O error in closing connection.");
}
}
}
LASTLY, here is what I have been coding today and cannot seem to get this to work. I don't get any blatant exceptions, just a warning on Logcat, that says, "Couldn't get I/O for the connection".
public class AndroidClientCompnt extends Activity {
private TcpClient myTcpClient = null;
private UdpClient udpClient;
private static final String IP_ADDRESS_SHARED_PREFS = "ipAddressPref";
private static final String PORT_SHARED_PREFS = "portNumberPref";
private String encryptPassLoginActivity;
private String getIpAddressSharedPrefs;
private String getPassword, getName, getRegionSelect, getGridSelect;
private String fName, lName;
private SharedPreferences settings;
private boolean resultCheck = false;
private int portNum;
PVDCAndroidClient client;
private String name;
private CharSequence[] getView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// setContentView(R.layout.main);
Intent intent = getIntent();
// getting object's properties from LoginActivity class.
getName = intent.getStringExtra("name");
getPassword = intent.getStringExtra("password");
getRegionSelect = intent.getStringExtra("regionSelect");
getGridSelect = intent.getStringExtra("gridSelect");
Log.d("VARIABLES", "getName = " + getName + "getPassword" + getPassword
+ "getRegionSelect = " + getRegionSelect + ".");
setResult(Activity.RESULT_CANCELED);
client = new PVDCAndroidClient();
}
#Override
protected void onStart() {
super.onStart();
// Take care of getting user's login information:
// grid selected as well? sometime?
settings = PreferenceManager.getDefaultSharedPreferences(this);
getIpAddressSharedPrefs = settings.getString(IP_ADDRESS_SHARED_PREFS,
"");
portNum = Integer.parseInt(settings.getString(PORT_SHARED_PREFS, ""));
Log.d("SHARED" + getIpAddressSharedPrefs + "port " + portNum, "");
if (getIpAddressSharedPrefs.length() != 0 && portNum != 0) {
try {
// first connect attempt.
client.connect(getIpAddressSharedPrefs, portNum);
resultCheck = client.isConnected();
// here is where I want to call Async to do login
// or do whatever else.
UploadTask task = new UploadTask();
task.execute();
} catch (Exception e) {
Toast.makeText(getApplicationContext(), "Could not connect.",
Toast.LENGTH_LONG).show();
e.printStackTrace();
}
} else {
Toast.makeText(getApplicationContext(),
"Ip preference and port blank", Toast.LENGTH_LONG).show();
}
finish();
}
private class UploadTask extends AsyncTask<String, Integer, Void> {
#Override
protected void onPreExecute() {
Toast.makeText(getApplicationContext(), "Loading...",
Toast.LENGTH_LONG).show();
}
#Override
protected Void doInBackground(String... names) {
// encrypting user's password with Md5Hash class.
try {
encryptPassLoginActivity = MdHashing
.MD5(getPassword.toString());
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (resultCheck == true) {
String[] firstAndLast;
String spcDelmt = " ";
firstAndLast = name.toString().split(spcDelmt);
fName = firstAndLast[0];
lName = firstAndLast[1];
// set up the tcp client to sent the information to the
// server.
client.login(fName, lName, encryptPassLoginActivity,
getRegionSelect, 128, 128, 20);
}
return null;
}
#Override
protected void onPostExecute(Void result) {
Intent goToInWorld = new Intent(
AndroidClientCompnt.this.getApplicationContext(),
PocketVDCActivity.class);
startActivity(goToInWorld);
Toast.makeText(getApplicationContext(), "Connected",
Toast.LENGTH_LONG).show();
}
}
}
I know this is a super long post and I am asking a lot but if anyone could take a look at this I would very much appreciate it. I've been at this all day, trying to make use of these helper classes I got and can't get it to work. It also doesn't help that I'm not too experienced in this client/server stuff. Any nudges in the right direction or an accepted solution would REALLY mean something to me.
Thank you kindly,
Have a good evening.

Can you post your manifest?
You may need to add the following :
<uses-permission android:name="android.permission.INTERNET"/>
Additionally - I assume you see nothing ever happen on the server side of this connection?

1) Make sure you have the following permission in your Android-Manifest file:
<uses-permission android:name="android.permission.INTERNET/>
w/o this you definitely won't be making any tcp/ip connections.
2) You will want to run the code in debug mode, and place breakpoints where the connection information
is set and also what results are at several points. In other words you need to dig deeper.
If you are somewhat new to coding there is no better investment of time than in running the debugger and stepping line by line through the code. Code only comes to life inside a debugger, where you can see the values of variables and results. So set several breakpoints, step through and you will see more. It is more difficult to debug where there are threads however.

Parsing large text file efficiency

Due to simplicity i have a text file with entries separated by ; and parses every line into an object. The problem is that the text file contains almost 10 000 rows.
I also need to create keys for each object im parsing so i can filter the results in a search interface.
It takes almost 16 seconds in emulator to parse the text and add the keys. I'm i doing something wrong here? Or is there a more efficient way?
Here is my database singleton:
public class Database {
private static Database instance = null; private final Map<String, List<Stop>> mDict = new ConcurrentHashMap<String, List<Stop>>();
public static Database getInstance() { if (instance == null) { instance = new Database(); } return instance; } public List<Stop> getMatches(String query) {
List<Stop> list = mDict.get(query);
return list == null ? Collections.EMPTY_LIST : list;
}
private boolean mLoaded = false;
/**
* Loads the words and definitions if they haven't been loaded already.
*
* #param resources Used to load the file containing the words and definitions.
*/
public synchronized void ensureLoaded(final Resources resources) {
if (mLoaded) return;
new Thread(new Runnable() {
public void run() {
try {
loadStops(resources);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}).start();
}
private synchronized void loadStops(Resources resources) throws IOException
{
if (mLoaded) return;
Log.d("database", "loading stops");
InputStream inputStream = resources.openRawResource(R.raw.allstops);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
try {
String line;
while((line = reader.readLine()) != null) {
String[] strings = TextUtils.split(line, ";");
addStop(strings[0], strings[1], strings[2]);
}
} finally {
reader.close();
}
Log.d("database", "loading stops completed");
mLoaded = true;
}
private void addStop(String name, String district, String id) {
Stop stop = new Stop(id, name, district);
int len = name.length();
for (int i = 0; i < len; i++) {
String prefix = name.substring(0, len - i).toLowerCase();
addMatch(prefix, stop);
}
}
private void addMatch(String query, Stop stop) {
List<Stop> matches = mDict.get(query);
if (matches == null) {
matches = new ArrayList<Stop>();
mDict.put(query, matches);
}
matches.add(stop);
}
}
Here is some sample data:
Mosseporten Senter;Norge;9021014089003000;59.445422;10.701055;273
Oslo Bussterminal;Norge;9021014089004000;59.911369;10.759665;273
Långegärde;Strömstad;9021014026420000;58.891462;11.007767;68
Västra bryggan;Strömstad;9021014026421000;58.893080;11.009997;7
Vettnet;Strömstad;9021014026422000;58.903184;11.020739;7
Ekenäs;Strömstad;9021014026410000;58.893610;11.048821;7
Kilesand;Strömstad;9021014026411000;58.878472;11.052983;7
Ramsö;Strömstad;9021014026430000;58.831531;11.067402;7
Sarpsborg;Norge;9021014089002000;59.280937;11.111763;273
Styrsö;Strömstad;9021014026180000;58.908110;11.115818;7
Capri/Källviken;Strömstad;9021014026440000;58.965200;11.124384;63
Lindholmens vändplan;Strömstad;9021014026156000;58.890212;11.128393;64
Öddö;Strömstad;9021014026190000;58.923490;11.130767;7
Källviksdalen;Strömstad;9021014026439000;58.962414;11.131962;64
Husevägen;Strömstad;9021014026505000;58.960094;11.133535;274
Caprivägen;Strömstad;9021014026284000;58.958404;11.134281;64
Stensviks korsväg;Strömstad;9021014026341000;59.001499;11.137203;63
Kungbäck;Strömstad;9021014026340000;59.006056;11.140313;63
Kase;Strömstad;9021014026173000;58.957649;11.141904;274

You should add the information into a SQLite database and ship the app with the database in res/raw.
Additionally, the db file can often be effectively compressed into a zip file.
See this for more information: Ship an application with a database

The fastest way to load that data into memory is to place it right into .java file. E.g. stopNames={"Stop1", "Stop2", ...}; latitudes={...};
I do this in my public transit app, loading similar amounts of the data this way takes under a second, filtering is instant.