Binary numbers play a significant role in modern computing. They are a basic building block for all digital devices.

A binary number is a number expressed in base-2 notation, which means it has a total of two possible values, 0 and 1. Every binary digit represents a power of two.

For instance, a binary number ‘10110’ represents the decimal value of 22. In this article, we will explore the methods for converting binary strings to integers in Java.

Method 1: Using Integer.parseInt()

The Integer.parseInt() method is a built-in Java method that converts a string to an integer value. This method works well for converting binary strings to integers.

Description of Integer.parseInt()

The signature for the Integer.parseInt() method is as follows:

public static int parseInt(String s, int radix) throws NumberFormatException {}

s – This is the string you want to convert to an integer. radix – This parameter sets the base value for the string representation.

In this case, we set the radix to 2, which means it is a binary string. base value – The base value is the value that a digit represents.

In this case, the base value is 2. Example of using Integer.parseInt()

In the example below, we will convert the binary value “1101” to an integer using the parseInt() method:

String binaryString = “1101”;

int decimalValue = Integer.parseInt(binaryString, 2);

System.out.println(decimalValue);

The output of this code will be 13, which is the decimal representation of the binary string.

One thing to note is that if the string you want to parse isn’t a valid binary string, the parseInt() method will throw a NumberFormatException.

Method 2: Using Math.pow()

Another method to convert a binary string to an integer value in Java is by using the Math.pow() method.

This method works by iterating over every character in the binary string and calculating the integer value using the Math.pow() method. Description of Math.pow()

The Math.pow() method is used to raise a number to a certain power.

## The method signature is:

public static double pow(double a, double b) {}

a – This is the base value. b – This is the exponent value that you want to raise a to.

Example of using Math.pow()

The example below shows how to convert a binary string to an integer using the Math.pow() method:

String binaryString = “1001”;

int decimalValue = 0;

for (int i = 0; i < binaryString.length(); i++) {

if (binaryString.charAt(i) == ‘1’) {

decimalValue += Math.pow(2, binaryString.length() – 1 – i);

}

}

System.out.println(decimalValue);

This code will output the value of “9”, which is the decimal value of the binary string “1001”.

## Conclusion

In this article, we have explored the two methods for converting binary strings to integers in Java. The first method is to use the built-in Java method, Integer.parseInt().

The second method uses the Math.pow() method by iterating through every character in the binary string. Both methods are effective in converting binary strings to integers in Java.

Binary strings are a popular way to store and transmit data in modern computing. In Java, there are two main methods to convert binary strings to integers.

In the previous sections, we have covered the first method, which uses Java’s built-in method, Integer.parseInt(). In this section, let us go over the second method, which utilizes the Math.pow() method.

## Checking characters in binaryString

Before we can use the Math.pow() method to convert binary strings to integers, we must first check each character in the binary string. A binary string contains only two possible characters, 0 or 1.

We could use a for loop to iterate through the string and check each character individually, like so:

String binaryString = “1101101”;

for (int i = 0; i < binaryString.length(); i++) {

char currentChar = binaryString.charAt(i);

if (currentChar == ‘0’) {

// do something

} else if (currentChar == ‘1’) {

// do something else

} else {

// invalid character, throw exception or handle it somehow

}

}

Here, we iterate through each character of the binary string and perform some action depending on whether the character is a ‘0’ or a ‘1’. In the else block, we could throw a NumberFormatException if an invalid character is found in the string.

## Checking occurrence of 1s in binaryString

Now that we can check each character in the binary string, we need to count how many of them are ‘1’s. The number of ‘1’s in a binary string affects the decimal value of the binary string.

For instance, the binary string “1101” has three ‘1’s, so its decimal equivalent is 13. We can track the number of ‘1’s in the string through a counter variable, like so:

String binaryString = “1101101”;

int numOnes = 0;

for (int i = 0; i < binaryString.length(); i++) {

char currentChar = binaryString.charAt(i);

if (currentChar == ‘1’) {

numOnes++;

}

}

Now, we know that the string “1101101” has four ‘1’s.

Using Math.pow() to convert binary to decimal

Finally, we can use the Math.pow() method to convert the binary string to a decimal value. We do this by starting from the leftmost digit of the binary string and multiplying its value by 2 raised to the power of the digit’s position.

We then move to the next digit and repeat the process until we reach the rightmost digit. Let us see how this works:

String binaryString = “1101101”;

int decimalValue = 0;

int power = binaryString.length() – 1; // start from the leftmost digit

for (int i = 0; i < binaryString.length(); i++) {

char currentChar = binaryString.charAt(i);

if (currentChar == ‘1’) {

decimalValue += Math.pow(2, power); // add to decimal value

}

power–; // move to next digit

}

In this code snippet, we calculate the decimal value of the binary string “1101101”.

We first initialize the decimal value to 0 and set the power variable to the position of the leftmost digit in the binary string. We then iterate through the binary string from left to right, checking each digit.

If the digit is a ‘1’, we add to the decimal value by calculating 2 raised to the power of the digit’s position and adding it to the decimal value. We then decrease the power variable by 1 to move on to the next digit.

At the end of the iteration, the decimalValue variable contains the decimal value of the binary string “1101101”, which is 109 in decimal notation.

## Conclusion

In this section, we have explored the Math.pow() method to convert binary strings to integers in Java. We first checked each character of the binary string, and then counted the number of ‘1’s in the string.

We then used the Math.pow() method to convert the binary string to decimal notation, working from the leftmost digit to the rightmost digit. These methods are essential for any programmer working with binary strings and provide a foundation of knowledge necessary for more advanced operations such as bitwise operators.

Binary strings are a fundamental component of modern computing, and the ability to convert them to integers is essential for working with them. This article covered two main methods in Java for converting binary strings to integers: Integer.parseInt() and Math.pow().

The first method utilizes Java’s built-in method for string-to-integer conversion, while the second method uses the Math.pow() method to convert binary strings to decimal notation. Both methods are efficient and provide a solid foundation for working with binary values.

Whether you’re a beginner programmer or an experienced developer, understanding binary values and their conversions is critical for building complex computing systems.