how to open a text file in java
// Java Program to illustrate reading from Text File
// using Scanner Class
import java.io.File;
import java.util.Scanner;
public class ReadFromFileUsingScanner
{
public static void main(String[] args) throws Exception
{
// pass the path to the file as a parameter
File file =
new File("C:\\Users\\pankaj\\Desktop\\test.txt");
Scanner sc = new Scanner(file);
while (sc.hasNextLine())
System.out.println(sc.nextLine());
}
}
// Java Program to illustrate reading from FileReader
// using Scanner Class reading entire File
// without using loop
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class ReadingEntireFileWithoutLoop
{
public static void main(String[] args)
throws FileNotFoundException
{
File file = new File("C:\\Users\\pankaj\\Desktop\\test.txt");
Scanner sc = new Scanner(file);
// we just need to use \\Z as delimiter
sc.useDelimiter("\\Z");
System.out.println(sc.next());
}
}
// Java Program to illustrate reading from
// FileReader using FileReader
import java.io.*;
public class ReadingFromFile
{
public static void main(String[] args) throws Exception
{
// pass the path to the file as a parameter
FileReader fr =
new FileReader("C:\\Users\\pankaj\\Desktop\\test.txt");
int i;
while ((i=fr.read()) != -1)
System.out.print((char) i);
}
}
// Java Program to illustrate reading from FileReader
// using BufferedReader
import java.io.*;
public class ReadFromFile2
{
public static void main(String[] args)throws Exception
{
// We need to provide file path as the parameter:
// double backquote is to avoid compiler interpret words
// like \test as \t (ie. as a escape sequence)
File file = new File("C:\\Users\\pankaj\\Desktop\\test.txt");
BufferedReader br = new BufferedReader(new FileReader(file));
String st;
while ((st = br.readLine()) != null)
System.out.println(st);
}
}
// Java program to illustrate reading data from file
// using nio.File
import java.util.*;
import java.nio.charset.StandardCharsets;
import java.nio.file.*;
import java.io.*;
public class ReadFileIntoList
{
public static List<String> readFileInList(String fileName)
{
List<String> lines = Collections.emptyList();
try
{
lines =
Files.readAllLines(Paths.get(fileName), StandardCharsets.UTF_8);
}
catch (IOException e)
{
// do something
e.printStackTrace();
}
return lines;
}
public static void main(String[] args)
{
List l = readFileInList("C:\\Users\\pankaj\\Desktop\\test.java");
Iterator<String> itr = l.iterator();
while (itr.hasNext())
System.out.println(itr.next());
}
}