Quick Answer: How do you return an index from a string in Java?

How do I return the index of a string?

The indexOf() method returns the index within the calling String object of the first occurrence of the specified value, starting the search at fromIndex . Returns -1 if the value is not found.

What does .indexOf do in Java?

The indexOf() method is used in Java to retrieve the index position at which a particular character or substring appears in another string. You can use a second argument to start your search after a particular index number in the string. If the specified letter or letters cannot be found, indexOf() returns -1.

How do you find the index of a specific value in a string?

Get the string and the index. Create an empty char array of size 1. Copy the element at specific index from String into the char[] using String.

Using String. charAt() method:

  1. Get the string and the index.
  2. Get the specific character using String. charAt(index) method.
  3. Return the specific character.

Can you index a string in Java?

Strings in Java are immutable. You can read a char from a specific index with charAt(int index) but you can not modify it. For that you would need to convert to a char array as you suggested and then build a new string from the array. To access the elements of a String by index, first convert to an array of char s.

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Can you index a string?

Strings are ordered sequences of character data, 00:15 and the individual characters of a string can be accessed directly using that numerical index. String indexing in Python is zero-based, so the very first character in the string would have an index of 0 , 00:30 and the next would be 1 , and so on.

What does find () mean in Python?

Definition and Usage

The find() method finds the first occurrence of the specified value. The find() method returns -1 if the value is not found. The find() method is almost the same as the index() method, the only difference is that the index() method raises an exception if the value is not found. (

What is charAt () in Java?

The Java charAt() method returns a character at a specific index position in a string. The first character in a string has the index position 0. … The Java charAt() method is used to find the character associated with a certain position in a string. It can also return multiple characters in a string.

What does .substring do in Java?

Java String substring() Method example.

The substring(int beginIndex, int endIndex) method of the String class. It returns a new string that is a substring of this string. The substring begins at the specified beginIndex and extends to the character at index endIndex – 1.

What is the index value of the last element of a string?

Characters in a string are indexed from left to right. The index of the first character is 0 , and the index of the last character is str. length – 1 .

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How do you find the value of a string?

Java String valueOf() method example

  1. public class StringValueOfExample{
  2. public static void main(String args[]){
  3. int value=30;
  4. String s1=String.valueOf(value);
  5. System.out.println(s1+10);//concatenating string with 10.
  6. }}

How do you find the index of a specific character in a string in python?

5 Ways to Find the Index of a Substring in Strings in Python

  1. str.find()
  2. str.rfind()
  3. str.index()
  4. str.rindex()
  5. re.search()