Reading and writing to a file in java

Introduction 

 

In this blog we will know how to read and write to a file in java.

/*File reading by using FileInputStream/FileReader*/
import  java.io.*;
import java.util.*;
public class readFile
{
public static void main(String arg[])throws Exception
{
System.out.print("Provide name of file to read ");
Scanner sc=new Scanner(System.in);
String s=sc.next();
//FileInputStream fis=new  FileInputStream(s);
FileReader fis=new  FileReader(s);
int x;
while((x=fis.read())!=-1)
System.out.print((char)x);
}
}

 

compile

 

javac readFile.java

java readFile

/*File writing by using FileOutputStream/FileWriter*/
import  java.io.*;
import java.util.*;
public class writeFile
{
public static void main(String arg[])throws Exception
{
Scanner sc=new Scanner(System.in);
System.out.print("Provide file name:");
String fname=sc.next();
System.out.print("Provide data to be written:");
String data=sc.next();
//To use FileWriter
 FileWriter fw=new FileWriter(fname,true);
 fw.write(data);
 fw.close();
}
}

 

compile

 

javac writeFile.java

java writeFile