A summary of read write method instances for text files in Java
- 2020-04-01 04:22:31
- OfStack
This example summarizes the read-write methods for text files in Java. Share with you for your reference, as follows:
Write text data
Method one:
import java.io.*;
public class A {
public static void main(String args[]) {
FileOutputStream out;
PrintStream ps;
try {
out = new FileOutputStream("a.txt");
ps = new PrintStream(out);
ps.println("qun qun.");
ps.println("fei fei");
ps.close();
} catch (Exception e) {
System.out.println(e.toString());
}
}
}
Method 2:
import java.io.*;
public class B {
public static void main(String args[]) {
FileWriter fw;
PrintWriter pw;
try {
fw = new FileWriter("b.txt");
pw = new PrintWriter(fw);
pw.print("qunqu n ");
pw.println("feiefi ss");
pw.print("qunqu n ");
pw.close();
fw.close();
} catch (IOException e) {
System.out.println(e.toString());
}
}
}
Method 3:
import java.io.*;
public class C {
public static void main(String args[]) {
String str_written = "This is a simple example";
try {
FileWriter fwriter = new FileWriter("c.txt");
BufferedWriter bfwriter = new BufferedWriter(fwriter);
bfwriter.write(str_written, 0, str_written.length());
bfwriter.flush();
bfwriter.close();
} catch (IOException e) {
System.out.println(e.toString());
}
}
}
Note: method 1 and method 2, method 3 are created when the operation text file does not exist, otherwise, when overwritten!
On the other; Methods three
BufferedWriter provides efficient writes of individual characters, arrays, and strings by writing text to the character output stream, buffering individual characters.
Attachment: append write:
import java.io.*;
public class C {
public static void main(String args[]) {
String str_written = "This is a simple example";
try {
FileWriter fwriter = new FileWriter("c.txt", true);
BufferedWriter bfwriter = new BufferedWriter(fwriter);
bfwriter.newLine();
bfwriter.write(str_written, 0, str_written.length());
bfwriter.flush();
bfwriter.close();
} catch (IOException e) {
System.out.println(e.toString());
}
}
}
Read text data
Method one:
import java.io.*;
public class A {
public static void main(String args[]) {
try {
FileInputStream fstream = new FileInputStream("a.txt");
DataInputStream in = new DataInputStream(fstream);
while (in.available() != 0) {
String a = in.readLine();
System.out.println(a);
System.out.println(a.length());
}
in.close();
} catch (Exception e) {
System.out.println(e.toString());
}
}
}
Method 2:
import java.io.*;
public class B {
public static void main(String args[]) {
try {
FileReader fr = new FileReader("a.txt");
BufferedReader br = new BufferedReader(fr);
String str;
int count = 0;
while ((str = br.readLine()) != null) {
count++;
System.out.println(count + " : " + str);
}
br.close();
fr.close();
} catch (Exception e) {
System.out.println(e.toString());
}
}
}
Attachment: method 2 can effectively read out the text data
I hope this article has been helpful to you in Java programming.