Java Tutorial

Java Tutorial Java Features C++ vs Java Java History Java Hello World Java Development Kit Java Runtime Environment Java Virtual Machine Difference between JDK, JRE, and JVM Memory Areas in Java Java Operators Java Keywords Primitive Data Types Variables

Java Loops

Java Do While Loop Java While Loop Java For Loop Java Enhanced For Loop

Java Programs

Java Basic Programs Factorial Program in Java Fibonacci Series Program in Java Prime Number Program in Java Palindrome Number Program in Java Armstrong Number Program in Java Anagram Program in Java Pattern Programs in Java Calculator Program in Java Leap Year Program in Java Addition Program in Java Number Pattern Programs in Java Star Pattern Programs in Java Package Program in Java Pyramid Program in Java Sorting Program in Java String Palindrome Program in Java Even Odd Program in Java For Loop Program in Java If Else Program in Java Switch Case Program in Java GCD Program in Java LCM Program in Java Hello Program in Java Matrix Program in Java Menu Driven Program in Java Series Program in Java Client Server Program in Java Swapping Program in Java Pig Latin Program in Java Tower of Hanoi Program in Java Recursion Program in Java Matrix Multiplication Program in Java Perfect Number Program in Java Classes and Objects in Java Example Programs String Programs in Java Array Programs in Java Constructor Program in Java Inheritance Program in Java Abstract class Program in Java Interface Program in Java Encapsulation Program in Java Polymorphism Program in Java Exception Handling Program in Java Multithreading Program in Java Thread Program in Java Collection Programs in Java ArrayList Program in Java Stack Program in Java Applet Program in Java Swing Program in Java JDBC Program in Java How to run Java program in command prompt How to run Java program in Eclipse Program to find and replace characters on string in java Program to find the duplicate characters in a string Program to check whether a given character is present in a string or not Java Program to Print Permutations of String Java program to find frequency of characters in a string Java Program to remove duplicate characters in a string

Java Sorting

Sorting Algorithms in Java Merge Sort in Java Quick Sort in Java Bubble Sort in Java Insertion Sort in Java Selection Sort in Java Heap Sort in Java Radix Sort in Java Topological Sort in Java Bucket Sort in Java Counting Sort in Java

Java OOPs Concepts

OOPs - Object Oriented Programming Objects and Classes in Java Methods in Java Java Naming Conventions Constructors in Java Java this keyword Java static keyword Inheritance in Java Aggregation in Java Java super keyword Constructor Chaining and Constructor Overloading Java Polymorphism Static and Dynamic Binding in Java Java Abstraction Abstract class in Java Interface in Java Difference between Abstract class and Interface Java final keyword Packages in Java Access Modifiers in Java Java Wrapper classes Java Numbers Java Characters Java Integer Java Boolean Java Arrays Java Command Line Arguments Java strictfp Keyword Java Math

Java Strings

Java Strings Java String Methods StringBuilder in Java StringBuffer in Java Java Regular Expressions StringBuffer vs StringBuilder String vs StringBuffer String vs StringBuilder String Manipulation in Java Java String Concatenation How to Reverse a String in Java String Array in Java How to Compare Two Strings in Java How to Concatenate Two Strings in Java Why String in Immutable in Java Java.lang.NumberFormatException for Input String String Pool in Java Java Generate Random String How to take String Input in Java Java String Interview Questions

Java Exceptions

Exception Handling in Java Java try catch Java throw Java throws Difference between throw and throws Java finally Java Custom Exception Java Exception Propagation

Garbage Collection

Automatic Resource Management in Java Java Garbage Collection Java finalize() Java gc() Difference between final, finally and finalize

Multithreading

Multithreading in Java Process and Thread in Java Basic Terms in Multithreading Java Thread creation Thread Scheduler in Java Java Thread class DeadLock in Java

Java IO

Java IO Java Read File Java file Reader Java Buffer Reader Java file Writer Java BufferedWriter Java InputStreamReader Scanner in Java Java StringReader Java StringReader Class Java PrintWriter Java File Java Read File Line By Line Java FileInputStream Java FileOutputStream Java Create File Java Delete File Java Open File Java Read File to String Java copy file Java Read JSON file Jar File in Java Java FileNotFoundException

Serialization

Java Serialization Java transient

Networking

Java Network Programming Java Socket Programming Java URL Java URLConnection HttpURLConnection in Java Java InetAddress Java DatagramSocket and Java DatagramPacket

AWT

Java AWT

Swing

Swing in Java

Java Collections

Collections in Java Java List Interface ArrayList in Java LinkedList in Java Vector in Java Stack in Java ArrayList vs LinkedList in Java ArrayList vs Vector in Java Java Set Interface HashSet in Java LinkedHashSet in Java TreeSet in Java Java Queue Interface PriorityQueue in Java ArrayDeque in Java Java Map Interface HashMap in Java LinkedHashMap in Java TreeMap in Java Dictionary in Java Hashtable in Java Properties in Java Collections class in Java Java Comparable Java Comparator Comparable vs Comparator in Java

Java Generics

Generics in Java

Java Annotations

Annotations in Java

Java JDBC

Java JDBC Tutorial JDBC Architecture Types of JDBC Drivers JDBC vs ODBC Java Database Connectivity with MySQL Statements in java Prepared statement in Java Resultset in java Java ResultSetMetaData DatabaseMetaData in Java Callable Statement in Java Transaction Management in java

Java Differences

Java vs JavaScript Python vs Java Kotlin vs Java Java vs C++ C# vs Java Static vs Non-static in Java C vs Java int vs Integer in Java Stack vs Heap in Java Java Array vs ArrayList

How to

How to run Java program How to set path in Java How to check the Java version in cmd How to install Java in Windows 10 How to run Java program in cmd How to add double quotes in a string in Java How to convert list to String in Java How to call a method in Java How to sort an array in Java How to iterate HashMap in Java How to write Java program How to create an array in Java How to create a package in Java How to generate random numbers in Java How to input String in Java How to create thread in Java How to find length of String in Java How to sort a string in Java How to use scanner in Java How to achieve multiple inheritance in Java How to find the length of an Array in Java How to run Java program in Eclipse How to call a function in Java How to create array of objects in Java How to create custom exception in Java How to import packages in Java How to run applet Program in Java How to take Array Input in Java How to achieve abstraction in Java How to call static method in Java How to compare characters in Java How to initialize string array in Java How to Install Java on MAC How to run java program in ubuntu How to find characters with the maximum number of times in a string java How to Set Java_home in Linux How to Split the String in Java with Delimiter How to Split String by Comma in Java How to remove special characters from String in Java How to remove last character from String in Java

Java 8 Features

Java 8 Features Lambda Expressions in Java Functional Interface in Java Streams in Java Java Base64 Encoding and Decoding Parallel Arrays Sort in Java

Java 9 Features

Java 9 Tutorial Java 9 Try With Resources Java 9 Interface Private Method

Java Servlet Tutorial

Java Servlets Tutorial

Java JSP Tutorial

Java JSP Tutorial

Hibernate Tutorial

Hibernate Tutorial

Spring Tutorial

Spring Tutorial

Spring MVC Tutorial

Spring MVC Tutorial

Jenkins Tutorial

Jenkins Tutorial

Java Math Methods

Math.abs() Math.acos() Math.addExact() Math.asin() Math.atan () Math.atan2() Math.cbrt() Math.ceil() Math.copysign() Math.cos() Math.cosh() Math.decrementExact() Math.exp() Math.expm1() Math.floor() Math.floorDiv() Math.floorMod() Math.getExponent() Math.hypot() Math.IEEEremainder() Math.incrementExact() Math.log() Math.log10() Math.log1p() Math.max() Math.min() Math.multiplyExact() Math.multiplyFull() Math.negateExact() Math.nextAfter() Math.nextDown() Math.nextUp() Math.pow() Math.random() Math.rint() Math.round() Math.scalb() Math.signum() Math.sin() Math.sinh() Math.sqrt() Math.subtractExact() Math.tan() Math.tanh() Math.toDegrees() Math.toIntExact() Math.toRadians() Math.ulp()

Java String Methods

toCharArray() copyValueOf() endsWith() equals() equalsIgnoreCase() format() getBytes() getChars() hashCode() indexOf() intern() isEmpty() join() lastIndexOf() length() replace() replaceAll() replaceFirst() split() startsWith() subSequence() substring() toLowerCase() toUpperCase() trim() valueOf()

Java Conversion

Java Convert String to int Java Convert int to String Java Convert String to long Java Convert long to String Java Convert String to float Java Convert float to String Java Convert String to double Java Convert double to String Java Convert String to Date Java Convert Date to String Java Convert String to Object Java Convert Object to String Java Convert String to char Java Convert char to String Java Convert int to long Java Convert long to int

Misc

Functional Interfaces in Java Singleton class in Java Awesome explanation of Strings in Java Object class in Java Static class in Java All the important string methods in Java String Handling Method in Java What are Array strings in Java Advantages and Disadvantages of Strings in Java Big Decimal class in Java Class definition in Java Char and String differences in Java Difference between String, StringBuffer and StringBuilder in java Replace character in string Java String Coding Interview Questions in Java What is String in Java? String isnullorempty in Java String Matches in Java Trim Method in String Java Bean class in Java Libraries in Java Arithmetic Operations on String in Java Convert Char array to string in java Check whether Java is installed or not How to calculate time difference in Java How to stop execution after a certain time in Java Jagged Array in Java Java ArraylistRemove() Time Complexity Java Swing Time Picker Zigzag Array in Java Array and String based questions in Java Array and String with Examples in Java Best Practices to use String Class in Java What is string in Java why it's immutable Java String Java String Inbuilt functions Java String Matches vs Contains Sum of digits in string in java Check the presence of Substring in a String in java Java import packages Interfaces and Classes in Strings in Java Maximum length of string in java Hidden classes in Java Class memory in Java public static void main string args meaning in java Reverse a String in Java String Concatenation in Java Difference between String and Char Array in Java Buffer reader to read string in Java

Java Create File

A File is a hypothetical way, which has no genuine presence. It is very much like while "using" that File that the major real activity of putting away something in an (enormous information) is large.

Exactly when the record is getting made by suggestion, the hypothetical way is getting made. The record is one way, in which data will be taken care of as per need.

Steps for creating a file in java:

Step1: Firstly to make a record there will be certainly special cases for defeating those us use attempt to get block procedures.

Step2: Now we will import the File class.

// to import java document

Import java.util.File;

// to make another document

 File  object_name = new File(directory)

To determine the working framework in the operating system the envelope is made in the work area itself however whereas in Linux and Mac the catalog is /clients/Bhoomika/work area/organizer

In windows the registry is gotten to as \\users\\bhoomika\\desktop\\folder

To make a file we have two strategies. We can get to those two strategies either straight by utilizing the File class or by implication by utilizing the file output stream class.

By utilizing File Class

By utilizing FileOutputStreamClass

  • File class:

    It is a class only utilized for dealing with
Technique: File.createNewFile()

 It is utilized for objects which don't have an actual presence

  • FileOutputStream class:

    A result stream can be written in FileOutputStream JavaDoc
Procedure: FileOutputStream

Model: echo>myFile.txt

It is used for objects which have a genuine presence

  • The two classes give a few techniques that are for the most part utilized in tasks with respect to files
// java program to create a file
// importing the files
import java.io.File;
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Demo
{
	Public static void main(String args[])
	{
		Demo d1= new Demo();
		d1.newFile();
	}
          Public void newFile()//strategy to make another document
	{
		String strpath = " ", strName =" ";
		//utilizing attempt try block  {
BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in));
Sytem.out.println("enter the document name you needed to access:");
			//perusing the record name
			strName = br.readLine();
Sytem.out.println("enter the record way you needed to access:");
//making the path for the file which we want
 file2 = new File(strPath + " "+ strName+" .txt");
//strategy to make a document
file2.createNewFile();
}
//attempt - get block
Get (Exception ex2){
}
}

Explanation of the above program:     

1. To make a file in java we utilized file class.

2.BufferedReader and InputStreamReader classes are utilized to make the files

Paths.

 3.These classes are put away under java.io package

4.Here class to be specific Demo and inside that class primary strategy is characterized

5.Inside the main object of the class is made

6.Outside the principal the new file is announced

7.As the file has its own name and way giving a name for it is method

8.To follow file name and way from the client as contribution here BufferedReader class and InputStreamReader class are utilized

9.To print the statement println() capability is utilized

10.readLine() strategy is utilized to take information and store it

11.".txt" is the organization of file expansion

12.Lastly attempt get block is utilized on the grounds that techniques like readLine() and createNewFile() strategies produces special case.

13. So to deal with that exception attempt get block is utilized

File createNewFile() method in java with examples:

  • The createNewFile() capability is a part of file class in java. This capability makes new void file.
  • It returns true if file does not exist and false if file name already exists.

Function signature:

Public Boolean createNewFile()

Syntax:

Boolean var = file.createNewFile();

Parameters:

This doesn’t accept any parameter

Return type:

This function returns Boolean data type

Exception:

This methods throws exception. They are

  1. IO EXCEPTION: if there is input output error this exception occurs
  2. SECURITY EXCEPTION: if the write access to file is denied this error occur
//program to illustrate the usage of create new file()
//java program showing createNewFile()
import java.io.*;
public class Question{
 	public static void main(String args[]){
		try{
			File f3=new File(“f3:\\programming.txt”);
			//creating the new file
			//using if-else block
if(f3.createNewFile())
System.out.println(“the file which you want is created”);
else
System.out.println(“the file which you want is already exsisted”);
}
catch(Exception e){
		System.err.println(e);
}
}

Saving a file in java:

  1. Switch to java programming
  2. .Create a java document or a current file
  3. If you need to make changes then, at that point, change the file
  4. When you wrapped up changing the file press save all

Java source is the file type and “.java” is the source

Java byte code is the file type and “.class” is the source

//creating a java file in directory 
 File f = new File(“C:/c/d/file.txt”);
//Java create file from string

PROCEDURE:

1.Create an example of file

2.Convert the string into a byte exhibit by utilizing string. getBytes technique()

3.write() with file example and byte cluster

//program to save a string to a file
// Java Program to Save a String to a File
// Using Files.writeString() method
// Importing required classes
import java.io.*;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
// Main class
public class Demo33 {
          // Main  method
	public static void main(String[] args)
	{
		// Creating an instance of file
		Path path= Paths.get("C:\\Users\\VICTUS\\Desktop\\Demo33.txt");
		// Custom string as an input
		String str= " \nWelcome to javatpoint \n Hello Bhoomika";
		// Try block for checking
		try {
			//  calling Files.writeString() method
			// with path, matter
			Files.writeString(path, str,StandardCharsets.UTF_8);
		}


		// Catch block 
		catch (IOException ex) {
			// Printing message exception came as
			// invalid. directory local path is passed
			System.out.print("Invalid Path searching for");
		}
	}
}

Methods used for the string program:

  1. writeString()
  2. write() for file class, file writer  and buffered class
  3. writer()

The file writer extends output stream writer and the output stream writer extend writer. The writer extends object.

It is the simple way of writing data on file.

Creating a new file in memory:

We can use stream based on a byte buffer which resides in memory by using input and output stream.



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