Check Balanced Parantheses in Java

Here’s an function implemented in Java to check whether a string contains balanced parentheses.

Examples

• isBalanced("((()))") returns true
• isBalanced("(()()())") returns true
• isBalanced("(()()()") returns false
• isBalanced("()())") returns false

Implementation

/**
 * Checks if the specified string has balanced parentheses.
 *
 * @param str
 *
 * @return	True, if the parentheses are balanced, false otherwise.
 */
public static boolean isBalanced(String str) {
	// Define the sum of the brackets.
	int sum = 0;
	// Loop through each character in the string.
	for(int i=0; i < str.length(); i++) {			
		// If the character is an open bracket, add 1.
		// If the character is a closed bracket, remove 1.
		if(str.charAt(i) == '('){
			sum += 1;
		} else if(str.charAt(i) == ')'){
			sum -= 1;<br />			
		}
	}
	// The total sum must be 0, if the brackets are balanced.
	// Otherwise, they are not balanced.
	return sum == 0;
}