Develop Reference

Reading a large text file with over 130000 line of text

How can i read a large text file into my Application?
This is my code but it does not work. My code must read a file called list.txt. The code worked only with a file with only 10.000 lines.
can someone helps me?
Thanks!
My code:(Worked with small files, but not with large files)
private void largefile(){
String strLine2="";
wwwdf2 = new StringBuffer();
InputStream fis2 = this.getResources().openRawResource(R.raw.list);
BufferedReader br2 = new BufferedReader(new InputStreamReader(fis2));
if(fis2 != null) {
try {
LineNumberReader lnr = new LineNumberReader(br2);
String linenumber = String.valueOf(lnr);
while ((strLine2 = br2.readLine()) != null) {
wwwdf2.append(strLine2 + "\n");
}
// Toast.makeText(getApplicationContext(), linenumber, Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), wwwdf2, Toast.LENGTH_LONG).show();
} catch (IOException e) {
e.printStackTrace();
}
}
}

Since you are processing a large file, you should process the data in chunks . Here your file reading is fine but then you keep adding all rows in string buffer and finally passing to Toast.makeText(). It creates a big foot-print in memory. Instead you can read 100-100 lines and call Toast.makeText() to process in chunks. One more thing, use string builder instead of string buffer go avoid unwanted overhead of synchronization. You initializing wwwdf2 variable inside the method but looks it is a instance variable which I think is not required. Declare it inside method to make it's scope shorter.

How to get specific information of an Android device from "/proc/cpuinfo" file?

How can I parse /proc/cpuinfo virtual file of my Android tablet to get information of the processor's core and clockspeed?
I don’t need all information provided by the above file; just these two bits.
Can someone please help?

It is not clear if you want this information inside your app, or just for your own use.
you can get this information on with adb:
adb shell cat /proc/cpuinfo
If you want to use this information in your app, create a simple function to return a Map<String,String>, for example,
public static Map<String, String> getCpuInfoMap() {
Map<String, String> map = new HashMap<String, String>();
try {
Scanner s = new Scanner(new File("/proc/cpuinfo"));
while (s.hasNextLine()) {
String[] vals = s.nextLine().split(": ");
if (vals.length > 1) map.put(vals[0].trim(), vals[1].trim());
}
} catch (Exception e) {Log.e("getCpuInfoMap",Log.getStackTraceString(e));}
return map;
}
Note, this will not get multiple cpus information, overwrites. Most of the values are similar anyways. or Modify to create List of CpuInfoMaps.
try,
Log.d("getCpuInfoMap test", getCpuInfoMap().toString());

I hope its not too late for an answer but, this is how i get the current frequency for a specific cpu core:
public class MainActivity extends Activity{
private static final int INSERTION_POINT = 27;
private static String getCurFrequencyFilePath(int whichCpuCore){
StringBuilder filePath = new StringBuilder("/sys/devices/system/cpu/cpu/cpufreq/scaling_cur_freq");
filePath.insert(INSERTION_POINT, whichCpuCore);
return filePath.toString();
}
public static int getCurrentFrequency(int whichCpuCore){
int curFrequency = -1;
String cpuCoreCurFreqFilePath = getCurFrequencyFilePath(whichCpuCore);
if(new File(cpuCoreCurFreqFilePath).exists()){
try {
BufferedReader br = new BufferedReader(new FileReader(new File(cpuCoreCurFreqFilePath)));
String aLine;
while ((aLine = br.readLine()) != null) {
try{
curFrequency = Integer.parseInt(aLine);
}
catch(NumberFormatException e){
Log.e(getPackageName(), e.toString());
}
}
if (br != null) {
br.close();
}
}
catch (IOException e) {
Log.e(getPackageName(), e.toString());
}
}
return curFrequency;
}
}
From here its a piece of cake, you simply call the method :-D
int core1CurrentFreq = getCurrentFrequency(1, this);
Sometimes the cores go offline, in which case the file path will not exist and -1 will be returned
NOTE. the returned value is in KHz
MHz value is core1CurrentFreq / 1e3
GHz value is core1CurrentFreq / 1e6
Some explainations on the getCurFrequencyFilePath() method since it is not all that clear.
Current frequency is usually stored in the file: scaling_cur_freq
The file path is:
"/sys/devices/system/cpu/cpu(XX)/cpufreq/scaling_cur_freq"
where (XX) is substituted for the cpu core number eg:
"/sys/devices/system/cpu/cpu2/cpufreq/scaling_cur_freq"
The INSERTION_POINT variable is nothing more than the index of (XX), the point at which we want to place the number corresponding to the cpu core
I suggest you take a look at some of the other files in the cpufreq folder, you can use them to get other information like maximum and minimum frequency, list of availables frequencies etc.
Click this
Link
and scroll down to heading 3

Find an unicode character in a txt - android

I am reading a txt file containing unicode characters. I need to find whether a specific unicode character exist in this file. The code so far is as follows,
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(getAssets().open("DistinctWords.txt"), "UTF-8"));
int i = 0;
String mLine = reader.readLine();
while ((mLine != null)) {
//process line
//unicode value taken from http://codepoints.net/U+0D85
if (mLine.contains("\u0D85")){
i++;
}
mLine = reader.readLine();
}
reader.close();
Log.i("tula", "Ayanna - " + String.valueOf(i));
} catch (IOException e) {
//log the exception
}
Problem: Value of "i" is always "0". When I open the same text file from notepad I can see the letter but my code fails to find it.

Like TronicZomB says, I think you need to be looking for the actual character, like:
while ((mLine != null)) {
//process line
if (mLine.contains("අ")){
i++;
}
mLine = reader.readLine();
}
You will want to use an editor that can handle the proper encoding:
Notepad on Windows will allow you to specify UTF-8 encoding on your file, but you have to set the encoding on the file to UTF-8 from ANSI.
On mac OS-x you can use TextEdit. In the preferences, with the open & save tab, you can set the document encoding.
On Linux StarOffice supposedly works, but I haven't used it.

Android - Comparing String Input On A Textfile Content

May I ask you to guide me how I can accomplish this problem?
I need to compare an inputWord to a string inside a .txt file and if found, return the whole line but if not, show "word not found".
Example:
inputWord: abacus
Text file content:
abaca - n. large herbaceous Asian plant of the banana family.
aback - adv. archaic towards or situated to the rear.
abacus - n. a frame with rows of wires or grooves along which beads are slid, used for calculating.
...
so on
Returns: abacus with its definition
What i am trying to do is compare my inputWord to the words before the " - " (hyphen as delimiter), if they dont match, move to the next line. If they match, copy the whole line.
I hope it doesnt seem like im asking you to "do my homework" but I tried tutorials around different forums and sites. I also read java docs but i really cannot put them together to accomplish this.
Thank you in advance!
UPDATE:
Here's my current code:
if(enhancedStem.startsWith("a"))
{
InputStream inputStream = getResources().openRawResource(R.raw.definitiona);
try {
BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
String s = in.readLine();
String delimiter = " - ";
String del[];
while(s != null)
{
s = in.readLine();
del = s.split(delimiter);
if (enhancedStem.equals(del[0]))
{
in.close();
databaseOutput.setText(s);
break;
}
}
in.close();
}
catch (FileNotFoundException e) {
databaseOutput.setText("" + e);
}
catch (IOException e1) {
databaseOutput.setText("" + e1);
}
}
Thanks a lot! Here's what I came up, and it returns the definition of inputs properly but the problem is, when i enter a word not found in the textfile, the app crashes. The catch phrase doesn't seem to work. Have any idea how I can trap it? Logcat says NullPointerExcepetion at line 4342 which is
s = in.readLine();

Assuming that the format of each line in the text file is uniform. This could be done in the following manner :
1) Read the file line by line.
2) Split each line based on the delimiter and collect the split String tokens in a temp String array.
3) The first entry in the temp token array will be the word before the "-" sign.
4) Compare the first entry in the temp array with the search string and return the entire line if there is a match.
Following code could be put up in a function to accomplish this :
String delimiter = "-";
String[] temp;
String searchString = "abacus";
BufferedReader in = new BufferedReader(new FileReader(file));
while (in.readLine() != null) {
String s = in.readLine();
temp = s.split(delimiter);
if(searchString.equals(temp[0])) {
in.close();
return s;
}
}
in.close();
return ("Word not found");
Hope this helps.

you may try like:
myreader = new BufferedReader(new FileReader(file));
String text = "MyInput Word";
while(!((text.equals(reader.readLine())).equals("0")));

Parse and Play a .pls file in Android

can anybody help me how to parse and play this .pls file in android
[playlist]
NumberOfEntries=1
File1=http://stream.radiosai.net:8002/

A quick search resulted in this very basic PlsParser from the NPR app that, by the looks of it, will simply parse the .pls file and return all embedded URLs in a list of strings. You'll probably want to take a look at that as a starting point.
After that, you should be able to feed the URL to a MediaPlayer object, although I'm not completely sure about what formats/protocols are supported, or what limitations might apply in the case of streaming. The sequence of media player calls will look somewhat like this.
MediaPlayer mp = new MediaPlayer();
mp.setDataSource("http://stream.radiosai.net:8002/");
mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
mp.prepare(); //also consider mp.prepareAsync().
mp.start();
Update: As far as I can tell, you can almost literally take the referenced code and put it your own use. Note that the code below is by no means complete or tested.
public class PlsParser {
private final BufferedReader reader;
public PlsParser(String url) {
URLConnection urlConnection = new URL(url).openConnection();
this.reader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
}
public List<String> getUrls() {
LinkedList<String> urls = new LinkedList<String>();
while (true) {
try {
String line = reader.readLine();
if (line == null) {
break;
}
String url = parseLine(line);
if (url != null && !url.equals("")) {
urls.add(url);
}
} catch (IOException e) {
e.printStackTrace();
}
}
return urls;
}
private String parseLine(String line) {
if (line == null) {
return null;
}
String trimmed = line.trim();
if (trimmed.indexOf("http") >= 0) {
return trimmed.substring(trimmed.indexOf("http"));
}
return "";
}
}
Once you have that, you can simply create a new PlsParser with the url of the .pls file and call getUrls afterwards. Each list item will be a url as found in the .pls file. In your case that'll just be http://stream.radiosai.net:8002/. As said, you can then feed this to the MediaPlayer.