Java Tutorial

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Java Loops

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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

Java Sorting

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Java OOPs Concepts

OOPs - Object Oriented Programming Objects and Classes 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 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 BufferedWriter Java InputStreamReader Java File Java Read File Line By Line Java FileOutputStream Jar File in Java


Java Serialization Java transient


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


Java AWT


Swing in Java

Java Collections

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Java Generics

Generics in Java

Java Annotations

Annotations in Java


Java JDBC Tutorial

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 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 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 achieve abstraction in Java How to call static method 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


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

Java BufferedWriter

BufferedWriter class is applied when there is a need buffer for Writer instance. BufferedWriter's major goal is to make programs more efficient while utilizing single characters, arrays, and strings. It inherits the Writer class. Like the buffered reader, BufferedWriter also has a buffer size that the user specifies, or the default size may be used. And the default size is large enough to fulfill most of the applications. Let’s understand buffer in brief.

What is Buffer?

A buffer is a section of memory storage that temporarily holds data and so makes use of RAM (random access memory). Because it stores temporary data, retrieving the stored data is similarly quick. Following is the example of Class Declaration for BufferedWriter

public class BufferedWriter extends Writer

How to Create a BufferedWriter?

1. First import the following package:

2. After the package is imported, we have to write the following code:

ileWriter a = new FileWriter(String name);
BufferedWriter b = new BufferedWriter(a);

The first line creates FileWriter with name a, and the second line of code creates BufferedWriter name b.

3. In the above code, we have created BufferedWriter, which has a default size(8192 characters)

We can also define the size of the buffer by adding size (which is a positive integer) beside the file name.

Constructors of BufferedWriter Class

1. BufferedWriter(Writer Out)

This constructor creates a buffered class that has default size.

2. BufferedWriter( Writer out, int n)

This constructor creates a new buffered class with a size defined by the user. The above keyword "n" indicates the output buffer size, and it should be a positive integer.

Methods of BufferedWriter Class

It gives the following methods, such as:

1. Write: It is divided into the following sections, such as:

  • Public void write (int a) throws IOException

When only a single character needs to be written, this is the method to employ. Int a specifies a character to be written.

  • Public void writes (char() arr, int o, int l) throws IOException.

This function generally inserts characters from the supplied array into this stream's buffer, flushing the buffer as needed to the underlying stream. If the desired length is at least as long as the buffer, this method will flush the buffer and write the characters directly to the underlying stream. It also does not return any value; instead, it flushes the characters and then closes the loop.

arr: character array.

Int o: offset from where to initiate reading.

Int l: indicates the number of characters to be typed

  • Public void write(String a, int o, int l)

No characters are printed if the length is negative. Int o from where to initiate reading. The number of characters is denoted by the letter l.

2. newLine: It doesn't return any value. It is used to separate a line.

public void newLine() throws IOexception

3. Flush: It flushes the buffer's character and doesn't return any value.

Public void flush() throws IOException

4. Close: It also doesn't return any value; instead, it flushes the characters before closing the window. So basically first flush() method is used, and then the close() method is implemented.

Public void close()

5. Append: It is used to insert a specified character.

Public void append()


The following code is an example of BufferedWriter.

Java BufferedWriter


We don't see anything in the output when we run the above code (except the line we have printed)

Java BufferedWriter Java BufferedWriter

However, we can see the result when we go back to our text file named apple.

Difference between BufferedWriter and FileWriter

Let's look at the differences between BufferedWriter and FileWriter.

It is simple of all the options to write a file.Similar to FileWriter but uses buffer concept.
Comparatively slower. Comparatively faster.
It is used when the number of write operations is less.It should be used when the number of write operations is more.

Apart from BufferedWriter and FileWriter, java uses two more ways to write a file operation.

  1. FileOutputStream: The above two options are designed to write text to files, but when we need raw stream data to be written into a file, we use FileOutputStream.   
  2. Files: The Files utility class was added in Java 7, and we may use its write method to create a file. Internally, it writes a byte array to a file using OutputStream.


If we need multiple writes between flush/close and the writes are small compared to the buffer size, BufferedWriter is what we need to make our code efficient.