// Create temp file

import java.io.File;
import java.io.IOException;
public class tempFile {
	public static void main(String args[])
		throws IOException
	{
		// name of the file
		String prefix = "TempFile";

		// extention of the file
		String suffix = ".txt";

		// Creating a File object for directory
		File directoryPath = new File(
			"/home/krishna/Desktop/java/junior/");

		// Creating a temp file
		File.createTempFile(prefix, suffix, directoryPath);
		System.out.println(
			"Temp file created at the specified path");
	}
}

Output: 

Temporary file has been created in the specified path

There are two ways you can delete an existing temporary file.

A. Delete when JVM exits:  

// Delete File when JVM Exists

import java.io.File;
import java.io.IOException;

public class tempFile {
	public static void main(String[] args)
	{
		File temp;
		try {
			// name of the file and extention
			temp = File.createTempFile("TempFile", ".txt");

			// Delete when JVM exits
			temp.deleteOnExit();
		}
		// If not found any temporary file
		catch (IOException e) {
			e.printStackTrace();
		}
	}
}

B. Delete the file immediately: 

We can delete a temporary file with the use delete() method.

// Delete file using delete() method

import java.io.File;
import java.io.IOException;

public class tempFile {
	public static void main(String[] args)
	{
		File temp;
		try {
			temp
				= File.createTempFile("myTempFile", ".txt");

			// Perform other operations
			// Delete the file immediately
			temp.delete();
		}
		// If not found the temperory file
		catch (IOException e) {
			e.printStackTrace();
		}
	}
}