Aatul Palandurkar

Archive for the ‘Java Tutorials’ Category

How to change editor full screen in NetBeans IDE?

Posted on: May 1, 2016

Objectives :

• How to change editor full screen in NetBeans IDE?

NetBeans IDE is having a new and great feature where we can full screen the code editor window.

This small video tutorial shows how to change editor full screen in NetBeans IDE?

Being a trainer, I need to share screen with code and sometime only code nothing else. This is one of the most useful feature for me while teaching Java technologies and UI technologies such as HTML5, CSS, JS, etc. This is why I love NetBeans IDE a lot.

Hope this tutorial is helpful for you as well.

Java Program to convert Decimal values to Hexadecimal values

Posted on: April 20, 2016

Objectives :

• How to convert Decimal to Hexadecimal in Java?

Java Program to convert Decimal values to Hexadecimal values :

```
import java.util.Scanner;

public static void main(String[] args) {

Scanner input = new Scanner(System.in);

System.out.print("Enter decimal number you like: ");
int deci = input.nextInt();

System.out.println("The hexadecimal number for decimal "
+ deci + " is " + convert(deci));
}

public static String convert(int decimal) {
String hex = "";

while (decimal != 0) {
int hexValue = decimal % 16;
decimal = decimal / 16;
}

return hex;
}

public static char toHexadecimal(int hexValue) {
if (hexValue <= 9 && hexValue >= 0) {
return (char) (hexValue + '0');
} else {
return (char) (hexValue - 10 + 'A');
}
}
}

```

Output :
Enter decimal number you like: 1234
The hexadecimal number for decimal 1234 is 4D2

Java Program to Convert Decimal Number to Roman Number

Posted on: March 28, 2016

Objectives :

• Convert Decimal number to Roman number
• Convert Decimal numeral to Roman numeral
• How to convert a decimal number to roman number
• Write a program that converts a decimal number to Roman number.
• Write a program that converts a decimal number to Roman number. Decimal Number is accepted using Scanner class at the time of execution.
• Write a program that converts a decimal number to Roman number. Decimal Number is accepted as command line input at the time of execution.

Program :

Java program that converts a decimal number to Roman number. Decimal Number is accepted using Scanner class at the time of execution.

```
&nbsp;

import java.util.Scanner;

public class DecimalToRoman {

private static String toRoman(int num) {
String[] romanCharacters = { "M", "CM", "D", "C", "XC", "L", "X", "IX", "V", "I" };
int[] romanValues = { 1000, 900, 500, 100, 90, 50, 10, 9, 5, 1 };
String result = "";

for (int i = 0; i < romanValues.length; i++) {
int numberInPlace = num / romanValues[i];
if (numberInPlace == 0) continue;
result += numberInPlace == 4 && i > 0? romanCharacters[i] + romanCharacters[i - 1]:
new String(new char[numberInPlace]).replace("\0",romanCharacters[i]);
num = num % romanValues[i];
}
return result;
}

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a number : ");
int decimal = scanner.nextInt();
System.out.println(toRoman(decimal));
}

}

```

Output :

Enter a number : 1234

MCCXXXIV

Java program that converts a decimal number to Roman number. Decimal Number is accepted as command line input at the time of execution.

```
public class DecimalToRoman {

private static String toRoman(int num) {
String[] romanCharacters = { "M", "CM", "D", "C", "XC", "L", "X", "IX", "V", "I" };
int[] romanValues = { 1000, 900, 500, 100, 90, 50, 10, 9, 5, 1 };
String result = "";

for (int i = 0; i < romanValues.length; i++) {
int numberInPlace = num / romanValues[i];
if (numberInPlace == 0) continue;
result += numberInPlace == 4 && i > 0? romanCharacters[i] + romanCharacters[i - 1]:
new String(new char[numberInPlace]).replace("\0",romanCharacters[i]);
num = num % romanValues[i];
}
return result;
}

public static void main(String[] args) {
if(args.length<1 || args.length>1){
System.out.println("Wrong input");
}else{
String number = args;
int decimal = Integer.parseInt(number);
System.out.println(toRoman(decimal));
}
}

}

```

Passing data between activities in Android

Posted on: March 19, 2016

Objective :

• Passing data between activities in Android
• Passing multiple data between activities in Android
• Passing array between activities in Android
• Passing ArrayList between activities in Android
• Passing ArrayList to another activity in Android
• Sending data via Intent in Android
• Sending multiple data via Intent in Android
• Sending array between activities in Android
• Sending ArrayList between activities in Android
• Sending ArrayList to another activity in Android
• Sending data via Intent and Bundle in Android
• Sending multiple data via Intent and Bundle in Android
• Passing array between activities in Android using Intent and Bundle
• How to pass array to another activity in Android?
• How to pass array between activities in Android?
• How to pass data to another activity in Android?
• How to pass data to activity in Android?
• How to pass data to between activities in Android?
• How to pass ArrayList to another activity in Android?
• How to pass ArrayList between activities in Android?

Code for passing data between activities in Android :

ActivityOne.java

```
String value = "Hello!";
Intent in = new Intent(this,ActivityTwo.class);
in.putExtra("Key", value);
startActivity(in);

```

ActivityTwo.java

```
Bundle bundle = getIntent().getExtras();

```

Code for passing multiple data or values between activities in Android :

Method 1 : Using Intent to pass data and Bundle to extract data between activities in Android

ActivityOne.java

```
String value1 = "Hello!";
String value2 = "Hi!";
Intent in = new Intent(this,ActivityTwo.class);
in.putExtra("Key1", value1);
in.putExtra("Key2", value2);
startActivity(in);
```

ActivityTwo.java

```Bundle bundle = getIntent().getExtras();
```

Method 2 : Using Bundle to pass and to extract data between activities in Android

ActivityOne.java

```
String value1 = "Hello!";
String value2 = "Hi!";
Intent in = new Intent(this,ActivityTwo.class);
Bundle bundle = new Bundle();
bundle.putString("Key1", value1);
bundle.putString("Key2", value2);
in.putExtras(bundle);
startActivity(in);
```

ActivityTwo.java

```Bundle bundle = getIntent().getExtras();
```

Code for passing array between activities in Android :

ActivityOne.java

```String[] array = new String[]{"Item1", "Item2", "item3", "Item4", "item5"};
Intent in = new Intent(this,ActivityTwo.class);
Bundle bundle = new Bundle();
bundle.putStringArray("MyArray", array);
in.putExtras(bundle);
startActivity(in);
```

ActivityTwo.java

```Bundle bundle = getIntent().getExtras();
```

Code for passing ArrayList between activities in Android :

ActivityOne.java

```ArrayList<String> array = new ArrayList<String>();
Intent intent = new Intent(this, ActivityTwo.class);
intent.putExtra("array_list", array);
startActivity(intent);
```

ActivityTwo.java

```Bundle bundle = getIntent().getExtras();
ArrayList<String> array = (ArrayList<String>) bundle.getStringArrayList("array_list");
```

Have fun with Intent.

Java Program to Convert Binary to Decimal

Posted on: March 16, 2016

Objectives :

• Binary to Decimal Conversion
• Converting Binary to Decimal
• Write a program to convert binary to decimal
• Write a program to convert binary number to decimal format
• Write a program to convert binary to decimal using Scanner class
• Write a program to convert binary to decimal, take input using Scanner class

Java Program :

```
import java.util.Scanner;

public class BinaryToDecimal {

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print(&quot;Enter binary number: &quot;);
String binary = scanner.nextLine();
int decimal = binaryToDecimal(binary);
System.out.println(&quot;Decimal equivalent of &quot;+ binary +&quot; is &quot;+ decimal);
}

private static int binaryToDecimal(String binary) {
final int base = 2;
int decimal = 0;
for (int i = 0; i &lt; binary.length(); i++) {
if (binary.charAt(i) == '0') {
decimal += 0 * Math.pow(base, binary.length() - i - 1);
} else if (binary.charAt(i) == '1') {
decimal += 1 * Math.pow(base, binary.length() - i - 1);
} else {
System.out.println(&quot;Invalid Binary Number&quot;);
System.out.println(&quot;Binary Number Contains only 0's or 1's&quot;);
System.exit(0);
}
}
return decimal;
}
}

```

Output :
Enter binary number: 1110
Decimal equivalent of 1110 is 14