This is used to return the substring from the specified beginIndex and endIndex.
What the function of substring(int beginIndex) method of StringBuilder class in java?
What the function of length() method of StringBuilder class in java?
What the function of charAt(int index) method of StringBuilder class in java?
What the function of ensureCapacity(int minimumCapacity) method of StringBuilder class in java?
What the function of capacity() method of StringBuilder class in java?