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adb logcat shows the code for emoji, but reading logcat programmatically loses the information

adb logcat captures the following:
I/System.out(10263): TEXT :<\d83d><\de48><\d83d><\de4a><\d83d><\de49><\d83d><\dc35>^M
which is encoding for emoji that shows up in the textview. (ignore the \es in the text above. I couldn't find a way to have the text show up in this post otherwise)
When I read the logcat programmatically using:
try {
Process process = Runtime.getRuntime().exec("logcat -d");
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream(),StandardCharsets.UTF_8));
String line = "";
PrintWriter writer = new PrintWriter("/sdcard/log.txt", "UTF-8");
while ((line = bufferedReader.readLine()) != null) {
writer.println(line);
}
writer.close();
} catch (IOException e) {
System.out.println(e.toString());
}
The same output line is:
I/System.out(10263): TEXT :��������
Any insight? Am I missing a simple encoding parameter between reading from the logs and writing to a file?

Why does introducing a FileWriter delete all the content in the file?

I have a text file with some text in it and i'm planning on replacing certain characters in the text file. So for this i have to read the file using a buffered reader which wraps a file reader.
File file = new File("new.txt");
BufferedReader br = new BufferedReader(new FileReader(file));
String line = null;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
But since i have to edit characters i have to introduce a file writer and add the code which has a string method called replace all. so the overall code will look as given below.
File file = new File("new.txt");
FileWriter fw = new FileWriter(file);
BufferedReader br = new BufferedReader(new FileReader(file));
String line = null;
while ((line = br.readLine()) != null) {
System.out.println(line);
fw.write(br.readLine().replaceAll("t", "1") + "\n");
}
Problem is when i introduce a file writer to the code (By just having the initialization part and when i run the program it deletes the content in the file regardless of adding the following line)
fw.write(br.readLine().replaceAll("t", "1") + "\n");
Why is this occurring? am i following the correct approach to edit characters in a text file?
Or is there any other way of doing this?
Thank you.

public FileWriter(String fileName,
boolean append)
Parameters:
fileName - String The system-dependent filename.
append - boolean if true, then data will be written to the end of the
file rather than the beginning.
To append data use
new FileWriter(file, true);

The problem is that you're trying to write to the file while you're reading from it. A better solution would be to create a second file, put the transformed data into it, then replace the first file with it when you're done. Or if you don't want to do that, read all of the data out of the file first, then open it for writing and write the transformed data.
Also, have you considered using a text-processing language solution such as awk, sed or perl: https://unix.stackexchange.com/questions/112023/how-can-i-replace-a-string-in-a-files

You need to read the file first, and then, only after you read the entire file, you can write to it.
Or you open a different file for writing and then afterwards you replace the old file with the new one.
The reason is that once you start writing to a file, it is truncated (the data that was in the file is deleted).
The only way to avoid that is to open the file in "append" mode. With that mode, you start writing at the end of the file, so you don't delete its content. However, you won't be able to modify the existing content, you will only add content.

Maybe like this
public static void main(String[] args) throws IOException {
try {
File file = new File("/Users/alexanderkrum/IdeaProjects/printerTest/src/atmDep.txt");
Scanner myReader = new Scanner(file);
ArrayList<Integer> numbers = new ArrayList<>();
while (myReader.hasNextLine()) {
numbers.add(myReader.nextInt() + 1);
}
myReader.close();
FileWriter myWriter = new FileWriter(file);
for (Integer number :
numbers) {
myWriter.write(number.toString() + '\n');
}
myWriter.close();
} catch (FileNotFoundException e) {
System.out.println("An error occurred.");
e.printStackTrace();
}
}

Just add at last :
fw.close();
this will close it ,then it will not delete anything in the file.
:)

Reading text from file in GUI

I am stuck at reading text from a file into text area.I don't know why but my file reader never opens the file even if it exists.I am getting file name from a text field and using a button listener to trigger this event.So any help will be appreciated. I've given my code to below.
try{
BufferedReader br = new BufferedReader(new FileReader(tf1.getText()));
while((read = br.readLine())!=null){
store = store + read;
}
ta.setText(store);
fr.close();
br.close();
jf2.dispose();
}
catch(Exception exp){
JOptionPane.showMessageDialog(null,"File Not Found.");
}

Change your code to something like this:
br = new BufferedReader(new FileReader(new File(tf1.getText())));
It is important to note that you need to have a "File" that encapsulates your text to open the actual file. Otherwise, the JVM does not know in which part of the harddisk to search for.
Good luck.

Java - ignoring certain characters while reading a text file

I'm trying to read a simple text file that contains the following:
LOAD
Bill's Beans
1200
20
15
30
QUIT
I need to store and print the contents line by line. I am doing so using the following code:
String inputFile = "(file path here)";
try {
Scanner input = new Scanner(inputFile);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
String currentLine = "";
while (!currentLine.equals("QUIT}")){
currentLine = input.nextLine();
System.out.println(currentLine);
}
input.close();
However, the output is very "messy". I am trying to avoid storing all new line characters and anything else that doesn't appear in the text file. Output is:
{\rtf1\ansi\ansicpg1252\cocoartf949\cocoasubrtf540
{\fonttbl\f0\fmodern\fcharset0 Courier;}
{\colortbl;\red255\green255\blue255;}
\margl1440\margr1440\vieww9000\viewh8400\viewkind0
\deftab720
\pard\pardeftab720\ql\qnatural
\f0\fs26 \cf0 LOAD\
Bill's Beans\
1200\
20\
15\
30\
QUIT}
Any help would be greatly appreciated, thank you!

This looks like you're reading a RTF file, isn't that so, by any chance?
Otherwise, I found reading text files is most natural for me using this construct:
BufferedReader reader = new BufferedReader(
new FileReader(new File("yourfile.txt")
);
String text = null;
// repeat until all lines is read
while ((text = reader.readLine()) != null) {
// do whatever with the text line
}
Because this is an RTF file, look into this for example: RTFEditorKit

If you insist on writing your own RTF reader, the correct approach would be for you to extend FilterInputStream and handle the RTF metadata in its implementation.

Just add following code into your class, then call it with path parameter. it returns all lines as List object
public List<String> readStudentsNoFromText(String path) throws IOException {
List<String> result = new ArrayList<String>();
// Open the file that is the first
// command line parameter
FileInputStream fstream = new FileInputStream(new File(path));
// 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);
result.add(strLine.trim());
}
//Close the input stream
in.close();
return result;
}

java file reading issue

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.