How to Encrypt and Decrypt Text in Android Using Cryptography?

How to Encrypt and Decrypt Text in Android Using Cryptography?

Last Updated : 25 Mar, 2025

Cryptography is a technique of securing information and communications through the use of codes so that only those people for whom the information is intended can understand it and process it. Thus preventing unauthorized access to information. The prefix “crypt” means “hidden” and suffix graphy means “writing”.

Project Overview

In this article, we will be building an Android Application that can Encrypt and Decrypt a message using the Encoding and Decoding algorithm respectively. The app's homepage will give the user two option:

Encryption: It is the process of transforming a readable message into an unreadable one. To do so we use encoding algorithms.
Decryption: It is the process of transforming data or information from an unreadable to readable form. To do so we use decoding algorithms.

Step by Step Implementation

Step 1: Create a New Project

To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio.

Note: Select Java/Kotlin as the programming language.

Step 2: Working with MainActivity and activity_main.xml file

In the MainActivity file, we will make the two buttons work in order to open the new activities. To do so we will use an Intent function that allows us to move from one activity to another. The two parameters of the Intent function are the current activity's class and the next activity's class. We will call this function inside onClickListener of the two buttons

The XML codes are used to build the structure of the activity as well as its styling part. On the homepage, we will have two buttons for Encryption and Decryption in the center of the activity. At the top, we will have a TextView for the title of the app.

MainActivity.java

package org.geeksforgeeks.demo;

import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {
    private Button encodeButton;
    private Button decodeButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        encodeButton = findViewById(R.id.btVar1);
        decodeButton = findViewById(R.id.btVar2);

        encodeButton.setOnClickListener(v -> {
            Intent intent = new Intent(MainActivity.this, Encoder.class);
            startActivity(intent);
        });

        decodeButton.setOnClickListener(v -> {
            Intent intent = new Intent(MainActivity.this, Decoder.class);
            startActivity(intent);
        });
    }
}

MainActivity.kt

package org.geeksforgeeks.demo

import android.content.Intent
import android.os.Bundle
import android.widget.Button
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {
    private lateinit var encodeButton: Button
    private lateinit var decodeButton: Button

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        encodeButton = findViewById<Button>(R.id.btVar1)
        decodeButton = findViewById<Button>(R.id.btVar2)

        encodeButton.setOnClickListener {
            val intent = Intent(
                this,
                Encoder::class.java
            )
            startActivity(intent)
        }

        decodeButton.setOnClickListener {
            val intent = Intent(
                this,
                Decoder::class.java
            )
            startActivity(intent)
        }
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:gravity="center"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/btVar1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="Encrypt"
        android:textSize="24sp" />

    <Button
        android:id="@+id/btVar2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="50dp"
        android:text="Decrypt"
        android:textSize="24sp" />

</LinearLayout>

Design UI:

cryptography-app-main

Step 3: Add Encode and Decode Algorithms

Create two Kotlin/Java file for encode and decode algorithms. Encoding algorithms are used to convert the text into an unreadable form, whereas Decoding algorithms are used to convert an encoded text into readable form. There are many algorithms that can be used to perform encryption and decryption. In this algorithm, we will be converting the text into a binary number using an Encryption algorithm. For this project, we will be using a customized algorithm. You can also use Base Type Encoding and Decoding Algorithms in Java.

Encode.java

public class Encode {
    public static String encode(String s) {
        // create a string to add in the initial
        // binary code for extra security
        String ini = "11111111";
        int cu = 0;
        
        // create an array
        int arr[] = new int[11111111];
        
        // iterate through the string
        for (int i = 0; i < s.length(); i++) {
            // put the ascii value of 
            // each character in the array
            arr[i] = (int) s.charAt(i);
            cu++;
        }
        String res = "";
        
        // create another array
        int bin[] = new int[111];
        int idx = 0;
        
        // run a loop of the size of string
        for (int i1 = 0; i1 < cu; i1++) {
            
            // get the ascii value at position
            // i1 from the first array
            int temp = arr[i1];
            
            // run the second nested loop of same size 
            // and set 0 value in the second array
            for (int j = 0; j < cu; j++) bin[j] = 0;
            idx = 0;
            
            // run a while for temp > 0
            while (temp > 0) {
                // store the temp module 
                // of 2 in the 2nd array
                bin[idx++] = temp % 2;
                temp = temp / 2;
            }
            String dig = "";
            String temps;
            
            // run a loop of size 7
            for (int j = 0; j < 7; j++) {
                
                // convert the integer to string
                temps = Integer.toString(bin[j]);
                
                // add the string using 
                // concatenation function
                dig = dig.concat(temps);
            }
            String revs = "";
            
            // reverse the string
            for (int j = dig.length() - 1; j >= 0; j--) {
                char ca = dig.charAt(j);
                revs = revs.concat(String.valueOf(ca));
            }
            res = res.concat(revs);
        }
        // add the extra string to the binary code
        res = ini.concat(res);
        
        // return the encrypted code
        return res;
    }
}

Decode.java

import android.util.Log;

public class Decode {
    public static String decode(String s) {
        String invalid = "Invalid Code";

        // create the same initial
        // string as in encode class
        String ini = "11111111";
        Boolean flag = true;

        // run a loop of size 8
        for (int i = 0; i < 8; i++) {
            // check if the initial value is same
            if (ini.charAt(i) != s.charAt(i)) {
                flag = false;
                break;
            }
        }
        String val = "";

        // reverse the encrypted code
        for (int i = 8; i < s.length(); i++) {
            char ch = s.charAt(i);
            val = val.concat(String.valueOf(ch));
        }

        // create a 2 dimensional array
        int arr[][] = new int[11101][8];
        int ind1 = -1;
        int ind2 = 0;

        // run a loop of size of the encrypted code
        for (int i = 0; i < val.length(); i++) {

            // check if the position of the
            // string if divisible by 7
            if (i % 7 == 0) {
                // start the value in other
                // column of the 2D array
                ind1++;
                ind2 = 0;
                char ch = val.charAt(i);
                arr[ind1][ind2] = ch - '0';
                ind2++;
            } else {
                // otherwise store the value
                // in the same column
                char ch = val.charAt(i);
                arr[ind1][ind2] = ch - '0';
                ind2++;
            }
        }
        // create an array
        int num[] = new int[11111];
        int nind = 0;
        int tem = 0;
        int cu = 0;

        // run a loop of size of the column
        for (int i = 0; i <= ind1; i++) {
            cu = 0;
            tem = 0;
            // convert binary to decimal and add them
            // from each column and store in the array
            for (int j = 6; j >= 0; j--) {
                int tem1 = (int) Math.pow(2, cu);
                tem += (arr[i][j] * tem1);
                cu++;
            }
            num[nind++] = tem;
        }
        String ret = "";
        char ch;
        // convert the decimal ascii number to its
        // char value and add them to form a decrypted
        // string using conception function
        for (int i = 0; i < nind; i++) {
            ch = (char) num[i];
            ret = ret.concat(String.valueOf(ch));
        }
        Log.e("dec", "text 11 - " + ret);

        // check if the encrypted code was
        // generated for this algorithm
        if (val.length() % 7 == 0 && flag == true) {
            // return the decrypted code
            return ret;
        } else {
            // otherwise return an invalid message
            return invalid;
        }
    }
}

Encode.kt

package org.geeksforgeeks.demo

object Encode {
    fun encode(s: String): String {
        // create a string to add in the initial
        // binary code for extra security
        val ini = "11111111"
        var cu = 0

        // create an array
        val arr = IntArray(11111111)

        // iterate through the string
        for (i in s.indices) {
            // put the ascii value of
            // each character in the array
            arr[i] = s[i].code
            cu++
        }
        var res = ""

        // create another array
        val bin = IntArray(111)
        var idx = 0

        // run a loop of the size of string
        for (i1 in 0 until cu) {
            // get the ascii value at position
            // i1 from the first array

            var temp = arr[i1]

            // run the second nested loop of same size
            // and set 0 value in the second array
            for (j in 0 until cu) bin[j] = 0
            idx = 0

            // run a while for temp > 0
            while (temp > 0) {
                // store the temp module
                // of 2 in the 2nd array
                bin[idx++] = temp % 2
                temp /= 2
            }
            var dig = ""
            var temps: String

            // run a loop of size 7
            for (j in 0..6) {
                // convert the integer to string
                temps = bin[j].toString()

                // add the string using
                // concatenation function
                dig += temps
            }
            var revs = ""

            // reverse the string
            for (j in dig.length - 1 downTo 0) {
                val ca = dig[j]
                revs += ca.toString()
            }
            res += revs
        }
        // add the extra string to the binary code
        res = ini + res

        // return the encrypted code
        return res
    }
}

Decode.kt

package org.geeksforgeeks.demo

import android.util.Log
import kotlin.math.pow

object Decode {
    fun decode(s: String): String {
        val invalid = "Invalid Code"

        // create the same initial
        // string as in encode class
        val ini = "11111111"
        var flag = true

        // run a loop of size 8
        for (i in 0..7) {
            // check if the initial value is same
            if (ini[i] != s[i]) {
                flag = false
                break
            }
        }
        var value = ""

        // reverse the encrypted code
        for (i in 8 until s.length) {
            val ch = s[i]
            value += ch.toString()
        }

        // create a 2 dimensional array
        val arr = Array(11101) { IntArray(8) }
        var ind1 = -1
        var ind2 = 0

        // run a loop of size of the encrypted code
        for (i in value.indices) {
            // check if the position of the
            // string if divisible by 7

            if (i % 7 == 0) {
                // start the value in other
                // column of the 2D array
                ind1++
                ind2 = 0
                val ch = value[i]
                arr[ind1][ind2] = ch.code - '0'.code
                ind2++
            } else {
                // otherwise store the value
                // in the same column
                val ch = value[i]
                arr[ind1][ind2] = ch.code - '0'.code
                ind2++
            }
        }
        // create an array
        val num = IntArray(11111)
        var nind = 0
        var tem = 0
        var cu = 0

        // run a loop of size of the column
        for (i in 0..ind1) {
            cu = 0
            tem = 0
            // convert binary to decimal and add them
            // from each column and store in the array
            for (j in 6 downTo 0) {
                val tem1 = 2.toDouble().pow(cu.toDouble()).toInt()
                tem += (arr[i][j] * tem1)
                cu++
            }
            num[nind++] = tem
        }
        var ret = ""
        var ch: Char
        // convert the decimal ascii number to its
        // char value and add them to form a decrypted
        // string using conception function
        for (i in 0 until nind) {
            ch = num[i].toChar()
            ret += ch.toString()
        }
        Log.e("dec", "text 11 - $ret")

        // check if the encrypted code was
        // generated for this algorithm
        return if (value.length % 7 == 0 && flag) {
            // return the decrypted code
            ret
        } else {
            // otherwise return an invalid message
            invalid
        }
    }
}

Step 4: Create the Encryption Layout

In the Encoder.java file, we will call the function that we created in the Step 5 (Encode.java) file. First, we will get the String from the EditText and then pass the value in the encode function. That will return us the encrypted code of the string. After that, we will set the code to a TextView and if it's not empty we will allow the user to copy the code in the clipboard. To perform the Encryption function onClick method is used in the button. Similarly, we have also set the onClick() function for copying the code in the clipboard for the button. Below is the code for the Encoder.java file. Comments are added inside the code to understand the code in more detail.

In the Encryption layout, we will have a TextView at top of the activity to display its title. Next, we will have a View to create a margin line. Next, there will be TextView and an EditText to input the text that is to be encrypted. Below that we will have a Button to encrypt the text. To display the encrypted code we have another TextView with a Button to copy it. Below is the XML code for the activity_encoder.xml file.

Encoder.java

package org.geeksforgeeks.demo;

import android.content.ClipData;
import android.content.ClipboardManager;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;

public class Encoder extends AppCompatActivity {
    private EditText editText;
    private TextView textView;
    private Button encryptButton, copyButton;
    private ClipboardManager clipboardManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_encoder);

        // Link the UI components with their respective IDs
        editText = findViewById(R.id.editText);
        textView = findViewById(R.id.encryptedTextView);
        encryptButton = findViewById(R.id.encryptButton);
        copyButton = findViewById(R.id.copyButton);

        // Initialize clipboard manager
        clipboardManager = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE);

        encryptButton.setOnClickListener(v -> {
            
            // Get user input
            String inputText = editText.getText().toString();
            
            // Call the encode function from the Encode class
            String encodedText = Encode.encode(inputText);
            
            // Display the encrypted text
            textView.setText(encodedText);
        });

        copyButton.setOnClickListener(v -> {
            
            // Get the text from the TextView
            String data = textView.getText().toString().trim();

            // Check if the TextView is not empty
            if (!data.isEmpty()) {
                
                // Copy the text to the clipboard
                ClipData copiedTextClip = ClipData.newPlainText("text", data);
                clipboardManager.setPrimaryClip(copiedTextClip);

                // Display a toast message that the text has been copied
                Toast.makeText(this, "Copied", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

Encoder.kt

package org.geeksforgeeks.demo

import android.content.ClipData
import android.content.ClipboardManager
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import org.geeksforgeeks.demo.Encode.encode


class Encoder : AppCompatActivity() {
    private lateinit var editText: EditText
    private lateinit var textView: TextView
    private lateinit var encryptButton: Button
    private lateinit var copyButton: Button

    private lateinit var clipboardManager: ClipboardManager

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_encoder)

        // link the edittext and textview with its id
        editText = findViewById(R.id.editText)
        textView = findViewById(R.id.encryptedTextView)
        encryptButton = findViewById(R.id.encryptButton)
        copyButton = findViewById(R.id.copyButton)


        // create a clipboard manager variable to copy text
        clipboardManager = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager

        encryptButton.setOnClickListener {
        
            // get user input
            val inputText = editText.text.toString()
            
            // call the encode function from the Encode class
            val encodedText = encode(inputText)
            
            // display the encrypted text
            textView.text = encodedText
        }

        copyButton.setOnClickListener {
            // get the text from the textview
            val data = textView.text.toString().trim { it <= ' ' }

            // check if the textview is not empty
            if (data.isNotEmpty()) {
                
                // copy the text in the clip board
                val copiedTextClip = ClipData.newPlainText("text", data)
                clipboardManager.setPrimaryClip(copiedTextClip)

                // display message that the text has been copied
                Toast.makeText(this, "Copied", Toast.LENGTH_SHORT).show()
            }
        }
    }
}

activity_encoder.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="32dp"
    tools:context=".Encoder">

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter your text here"
        android:textSize="24sp" />

    <Button
        android:id="@+id/encryptButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Encrypt"
        android:textSize="24sp" />

    <TextView
        android:id="@+id/encryptedTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:text="encrypted text goes here..."
        android:textSize="24sp" />


    <Button
        android:id="@+id/copyButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Copy"
        android:textSize="24sp" />

</LinearLayout>

Design UI:

cryptography-app-encrypt

Step 7: Create the Decryption Layout

In the Decoder.java file, we will call the function that we created in the Step 5 (Decode.java) file. First, we will get the encrypted code from the EditText and then pass the value in the decode function. That will return us the decrypted text of the string. After that, we will set the text to a TextView, and if it's not empty we will allow the user to copy the code in the clipboard. To perform the Decryption function onClick() method is used in the button. Similarly, we have also set the onClick() function for copying the code in the clipboard for the button. Below is the code for the Decoder.java file. Comments are added inside the code to understand the code in more detail.

In the Decryption layout, we will have a TextView at top of the activity to display its title. Next, we will have a View to create a margin line. Next, there will be TextView and an EditText to input the encrypted code that is to be decrypted. Below that we will have a Button to decrypt the text. To display the decrypted code we have another TextView with a Button to copy it. Below is the XML code for the activity_decoder.xml file.

Decoder.java

package org.geeksforgeeks.demo;

import android.content.ClipData;
import android.content.ClipboardManager;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;

public class Decoder extends AppCompatActivity {
    private EditText editText;
    private TextView textView;
    private Button decryptButton, copyButton;
    private ClipboardManager clipboardManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_decoder);

        // Link UI components with their respective IDs
        editText = findViewById(R.id.editText);
        textView = findViewById(R.id.decryptedTextView);
        decryptButton = findViewById(R.id.decryptButton);
        copyButton = findViewById(R.id.copyButton);

        // Initialize clipboard manager
        clipboardManager = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE);

        decryptButton.setOnClickListener(v -> {
            // Get the string from the edit text
            String inputText = editText.getText().toString();
            // Call the decode function from the Decode class
            String decodedText = Decode.decode(inputText);
            // Set the decoded text to the text view for display
            textView.setText(decodedText);
        });

        copyButton.setOnClickListener(v -> {
            // Get the text from the text view
            String data = textView.getText().toString().trim();

            // Check if the text view is not empty
            if (!data.isEmpty()) {
                // Copy the text to the clipboard
                ClipData copiedTextClip = ClipData.newPlainText("text", data);
                clipboardManager.setPrimaryClip(copiedTextClip);

                // Display a toast message that the text has been copied
                Toast.makeText(this, "Copied", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

Decoder.kt

package org.geeksforgeeks.demo

import android.content.ClipData
import android.content.ClipboardManager
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import org.geeksforgeeks.demo.Decode.decode


class Decoder : AppCompatActivity() {
    private lateinit var editText: EditText
    private lateinit var textView: TextView
    private lateinit var decryptButton: Button
    private lateinit var copyButton: Button

    private lateinit var clipboardManager: ClipboardManager

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_decoder)

        editText = findViewById(R.id.editText)
        textView = findViewById(R.id.decryptedTextView)
        decryptButton = findViewById(R.id.decryptButton)
        copyButton = findViewById(R.id.copyButton)

        // create a clipboard manager variable to copy text
        clipboardManager = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager

        decryptButton.setOnClickListener {
            // get the string from the edit text
            val inputText = editText.text.toString()
            // call the decode function from the Decode class
            val decodedText = decode(inputText)
            // set the text to the edit text for display
            textView.text = decodedText
        }

        copyButton.setOnClickListener {
            // get the text from the textview
            val data = textView.text.toString().trim { it <= ' ' }

            // check if the textview is not empty
            if (data.isNotEmpty()) {
                // copy the text in the clip board
                val copiedTextClip = ClipData.newPlainText("text", data)
                clipboardManager.setPrimaryClip(copiedTextClip)

                // display message that the text has been copied
                Toast.makeText(this, "Copied", Toast.LENGTH_SHORT).show()
            }
        }
    }
}

activity_decoder.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="32dp"
    tools:context=".Decoder">

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter your text here"
        android:textSize="24sp" />

    <Button
        android:id="@+id/decryptButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Decrypt"
        android:textSize="24sp" />

    <TextView
        android:id="@+id/decryptedTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:text="decrypted text goes here..."
        android:textSize="24sp" />

    <Button
        android:id="@+id/copyButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Copy"
        android:textSize="24sp" />

</LinearLayout>

Design UI:

cryptography-app-decrypt

Refer to the following github repo for the entire code: Encrypt_Decrypt_Text_Android

Output:

How to Encrypt and Decrypt Text in Android Using Cryptography?

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Java is a high-level, object-oriented programming language used to build web apps, mobile applications, and enterprise software systems. It is known for its Write Once, Run Anywhere capability, which means code written in Java can run on any device that supports the Java Virtual Machine (JVM).Java s

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Java Object-Oriented Programming (OOPs) is a fundamental concept in Java that every developer must understand. It allows developers to structure code using classes and objects, making it more modular, reusable, and scalable.The core idea of OOPs is to bind data and the functions that operate on it,

Java Interview Questions and Answers

Java is one of the most popular programming languages in the world, known for its versatility, portability, and wide range of applications. Java is the most used language in top companies such as Uber, Airbnb, Google, Netflix, Instagram, Spotify, Amazon, and many more because of its features and per

Arrays in Java are one of the most fundamental data structures that allow us to store multiple values of the same type in a single variable. They are useful for storing and managing collections of data. Arrays in Java are objects, which makes them work differently from arrays in C/C++ in terms of me

Inheritance in Java

Java Inheritance is a fundamental concept in OOP(Object-Oriented Programming). It is the mechanism in Java by which one class is allowed to inherit the features(fields and methods) of another class. In Java, Inheritance means creating new classes based on existing ones. A class that inherits from an

Collections in Java

Any group of individual objects that are represented as a single unit is known as a Java Collection of Objects. In Java, a separate framework named the "Collection Framework" has been defined in JDK 1.2 which holds all the Java Collection Classes and Interface in it. In Java, the Collection interfac

Java Exception Handling

Exception handling in Java allows developers to manage runtime errors effectively by using mechanisms like try-catch block, finally block, throwing Exceptions, Custom Exception handling, etc. An Exception is an unwanted or unexpected event that occurs during the execution of a program, i.e., at runt

An Interface in Java programming language is defined as an abstract type used to specify the behaviour of a class. An interface in Java is a blueprint of a behaviour. A Java interface contains static constants and abstract methods. Key Properties of Interface:The interface in Java is a mechanism to

Java Programs - Java Programming Examples

In this article, we will learn and prepare for Interviews using Java Programming Examples. From basic Java programs like the Fibonacci series, Prime numbers, Factorial numbers, and Palindrome numbers to advanced Java programs.Java is one of the most popular programming languages today because of its

Polymorphism in Java

Polymorphism in Java is one of the core concepts in object-oriented programming (OOP) that allows objects to behave differently based on their specific class type. The word polymorphism means having many forms, and it comes from the Greek words poly (many) and morph (forms), this means one entity ca