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File Handling(File class-1)

File Handling:-File is a class in java present in java.io package, constructor of this class is not creating physical file, where it is used to hold the physical file if file is exist. Using file object we cannot perform read write operation.

Example1:- TestFile
import java.io.File;
class TestFile
{
public static void main(String[]args)
{
File f=new File("abc.txt");
System.out.println(f);
System.out.println("f is capable to hold file abc.txt phisical file not created");
}
}
Output:- C:\JAVATECH>javac TestFile.java
C:\JAVATECH>java TestFile
abc.txt
f is capable to hold file abc.txt phisical file not created

Example2:- TestFile
import java.io.File;
class TestFile
{
public static void main(String[]args)
{
File f=new File("abc.txt");
boolean b=f.exists();
if(b)
System.out.println("file exist");
else
System.out.println("file not  exist");
}
}
Output:- C:\JAVATECH>javac TestFile.java
C:\JAVATECH>java TestFile
file not  exist

Example3:- TestFile
import java.io.File;
import java.io.*;
class TestFile
{
public static void main(String[]args)throws IOException
{
File f=new File("abc.txt");
f.createNewFile();
boolean b=f.exists();
if(b)
System.out.println("file exist");
else
System.out.println("file not  exist");
}
}
Output:- C:\JAVATECH>javac TestFile.java
C:\JAVATECH>java TestFile
file exist

Example4:- TestFile
import java.io.File;
import java.io.*;
class TestFile
{
public static void main(String[]args)throws IOException
{
File f=new File("ABC");
f.mkdir();
boolean b=f.exists();
if(b)
System.out.println("Directory exist");
else
System.out.println("Directory not  exist");
}
}
Output:- C:\JAVATECH>javac TestFile.java
C:\JAVATECH>java TestFile
Directory exist

Example5:- TestFile
import java.io.File;
import java.io.*;
class TestFile
{
public static void main(String[]args)throws IOException
{
File f=new File("ABC");
f.mkdir();
if(f.isFile())
System.out.println("Yes it is file exist");
if(f.isDirectory())
System.out.println("Yes it  Directory ");
}
}
Output:- C:\JAVATECH>javac TestFile.java
C:\JAVATECH>java TestFile

Yes it  Directory
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