I have a problem. I am using a file to load some strings to use them in my App.
I have this function:
public void lecturaFichero(){
String linea = null;
try {
InputStream in = cntx.getAssets().open("cc.txt");
if (in != null) {
InputStreamReader input = new InputStreamReader(in,Charset.forName("iso-8859-1"));
BufferedReader buffreader = new BufferedReader(input);
while ((linea = buffreader.readLine()) != null) {
rellenaCodigo(linea);
}
in.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
The problem is that when I run the app it crashes right away (reading the file is the first thing I do).
If I do this instead of the above:
InputStreamReader input = new InputStreamReader(in)); //Without specifying the charset
It does work, it does not crash but the app shows where that special characters should be.
I need to solve this, I'd appreciate a solution in which I can read special characters in my app.
Thanks in advance.
PS: Android can print special characters because when I type a String by hand and print it on the screen it shows the character, the problem is when it comes to reading from the .txt.
Related
I am trying to read a file, but I get a NoSuchFileException. I know my code work, because it works in another program I have created, but it doesn't work now. Yes the directory is correct and there is a text file in the src folder. Please could someone tell me how to fix this.
String[] words = new String[5];
Path file = Paths.get("H:\\Varsity work\\Java Programming\\Programs\\HangMan\\build\\classes\\HangMan.txt");
InputStream input = null;
try {
input = Files.newInputStream(file);
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
String s = null;
while((s=reader.readLine())!=null) {
System.out.println(s);
}
input.close();
} catch(Exception e) {
System.out.println(e);
}
try using '/' instead of '\' , so no need to escape any chars and path string used as is.
I am trying to save the multiple line output in a text file from my jTextArea(named as "outputarea" in a code) to my desired path, Everything is OK but the file being saved do not contain the whole output, but only first line oof text. I am using "\n" to break the line in jtextarea while giving multiple line output, does that make any difference or any other problem in this code, This code is just the code on saveAs button, output is coming from another methods I've created. Thanks in Advance!
private void saveAs() {
FileDialog fd = new FileDialog(home.this, "Save", FileDialog.SAVE);
fd.show();
if(fd.getFile()!=null)
{
fn=fd.getFile();
dir=fd.getDirectory();
filename = dir + fn +".txt";
setTitle(filename);
try
{
DataOutputStream d=new DataOutputStream(new FileOutputStream(filename));
holdText = outputarea.getText();
BufferedReader br = new BufferedReader(new StringReader(holdText));
while((holdText = br.readLine())!=null)
{
d.writeBytes(holdText+"\r\n");
d.close();
}
}
catch (Exception e)
{
System.out.println("File not found");
}
outputarea.requestFocus();
save(filename);
}
}
You should put the d.close(); after the completion of while loop, because just after writing the first line in the file using DataOutputStream, you are closing it and you don't let it to fulfill the whole job.
You can see even an error is wrote in your console:
File not found
This is not because it doesn't find your file, it's because in the iterations after the first, it tries to write into a closed stream. So only the first line is wrote then. So change you code like this:
while ((holdText = br.readLine()) != null) {
d.writeBytes(holdText + "\r\n");
}
d.close();
Also I can advise to use a PrintWriter instead of DataOutputStream. Then you can easily change the writeBytes into println method. In this way you don't need to append \r\n manually to each line you write.
Another good hint is to use a try-with-resource (in case you use java 7 or later) or at least a finally block to close your streams either way:
String holdText = outputarea.getText();
try (PrintWriter w = new PrintWriter(new File(filename));
BufferedReader br = new BufferedReader(new StringReader(holdText))) {
while ((holdText = br.readLine()) != null) {
w.println(holdText);
}
} catch (Exception e) {
System.out.println("File not found");
}
Good Luck.
I have a problem with reading a ULR response. On Android it only reads around the half of the response.
If I use the same code in a normal Java project everything works fine.
try {
String _output = null;
URL url = new URL("http://example.com");
BufferedReader buffer = new BufferedReader(new InputStreamReader(url.openStream()));
StringBuilder everything = new StringBuilder();
String line;
while ((line = buffer.readLine()) != null) {
everything.append(line);
}
_output = everything.toString();
buffer.close();
System.out.print(_output);
} catch (IOException e) {
e.printStackTrace();
}
How do you know that it's only half of the response? If you rely on what is printed with System.out.println() then you should be aware that Logcat has a limitation that prevents it from printing more than 4,000 characters. Anything after that is truncated. To check how much of the response you have, you could print everything.length()first, ot see if you are in that situation.
You can look at this existing question on SO for reference, but there are many others.
I have a text file called "high.txt". I need the data inside for my Android app. But I have absolutely no idea how to read it into an ArrayList of the Strings. I tried the normal way of doing it in Java but apparently that doesn't work in Android since it cant find the file. So how do I go about doing this? I have put it in my res folder. But how do you take the input stream that you get from opening the file within Android and read it into an ArrayList of Strings. I am stuck on that part.
Basically it would look something like this:
3. What do you do for an upcoming test?
L: make sure I know what I'm studying and really review and study for this thing. Its what Im good at. Understand the material really well.
CL: Time to study. I got this, but I really need to make sure I know it,
M: Tests can be tough, but there are tips and tricks. Focus on the important, interesting stuff. Cram in all the little details just to get past this test.
CR: -sigh- I don't like these tests. Hope I've studied enough to pass or maybe do well.
R: Screw the test. I'll study later, day before should be good.
This is for a sample question and all the lines will be stored as separate strings in the array list.
If you put the text file in your assets folder you can use code like this which I've taken and modified from one of my projects:
public static void importData(Context context) {
try {
BufferedReader br = new BufferedReader(new InputStreamReader(context.getAssets().open("high.txt")));
String line;
while ((line = br.readLine()) != null) {
String[] columns = line.split(",");
Model model = new Model();
model.date = DateUtil.getCalendar(columns[0], "MM/dd/yyyy");
model.name = columns[1];
dbHelper.insertModel(model);
}
} catch (IOException e) {
e.printStackTrace();
}
}
Within the loop you can do anything you need with the columns, what this example is doing is creating an object from each row and saving it in the database.
For this example the text file would look something like this:
15/04/2013,Bob
03/03/2013,John
21/04/2013,Steve
If you want to read file from External storage than use below method.
public void readFileFromExternal(){
String path = Environment.getExternalStorageDirectory().getPath()
+ "/AppTextFile.txt";
try {
BufferedReader reader = new BufferedReader(new FileReader(path));
String line, results = "";
while( ( line = reader.readLine() ) != null)
{
results += line;
}
reader.close();
Log.d("FILE","Data in your file : " + results);
} catch (Exception e) {
}
}
//find all files from folder /assets/txt/
String[] elements;
try {
elements = getAssets().list("txt");
} catch (IOException e) {
e.printStackTrace();
}
//for every files read text per line
for (String fileName : elements) {
Log.d("xxx", "File: " + fileName);
try {
InputStream open = getAssets().open("txt/" + fileName);
InputStreamReader inputStreamReader = new InputStreamReader(open);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
String line = "";
while ((line = bufferedReader.readLine()) != null) {
Log.d("xxx", line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
In my java application, I have to read one file. The problem what I am facing, after reading the file, the results is coming as non readable format. that means some ascii characters are displayed. That means none of the letters are readable. How can I make it display that?
// Open the file that is the first
// command line parameter
FileInputStream fstream = new FileInputStream("c:\\hello.txt");
// Get the object of DataInputStream
DataInputStream in = new DataInputStream(fstream);
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String strLine;
// Read File Line By Line
while ((strLine = br.readLine()) != null) {
// Print the content on the console
System.out.println(strLine);
}
// Close the input stream
in.close();
} catch (Exception e) {// Catch exception if any
System.err.println("Error: " + e.getMessage());
}
Perhaps you have an encoding error. The constructor you are using for an InputStreamReader uses the default character encoding; if your file contains UTF-8 text outside the ASCII range, you will get garbage. Also, you don't need a DataInputStream, since you aren't reading any data objects from the stream. Try this code:
FileInputStream fstream = null;
try {
fstream = new FileInputStream("c:\\hello.txt");
// Decode data using UTF-8
BufferedReader br = new BufferedReader(new InputStreamReader(in, "UTF-8"));
String strLine;
// Read File Line By Line
while ((strLine = br.readLine()) != null) {
// Print the content on the console
System.out.println(strLine);
}
} catch (Exception e) {// Catch exception if any
System.err.println("Error: " + e.getMessage());
} finally {
if (fstream != null) {
try { fstream.close(); }
catch (IOException e) {
// log failure to close file
}
}
}
The output you are getting is an ascii value ,so you need to type cast it into char or string before printing it.Hope this helps
You have to implement this way to handle:-
BufferedReader br = new BufferedReader(new InputStreamReader(in, encodingformat));
.
encodingformat - change it according to which type of encoding issue you are encounter.
Examples: UTF-8, UTF-16, ... soon
Refer this Supported Encodings by Java SE 6 for more info.
My problem got solved. I dont know how. I copied the hello.txt contents to another file and run the java program. I could read all letters. dont know whats the problem in that.
Since you doesn't know the encoding the file is in, use jchardet to detect the encoding used by the file and then use that encoding to read the file as others have already suggested. This is not 100 % fool proof but works for your scenario.
Also, use of DataInputStream is unnecessary.