The syntax of the substring()
method is:
string.substring(int startIndex, int endIndex)
Here, string is an object of the String
class.
substring() Parameters
The substring()
method takes two parameters.
- startIndex - the begining index
- endIndex (optional) - the ending index
substring() Return Value
The substring()
method returns a substring from the given string.
- The substring begins with the character at the startIndex and extends to the character at index
endIndex - 1
. - If the endIndex is not passed, the substring begins with the character at the specified index and extends to the end of the string.

Note: You will get an error if,
- startIndex/endIndex is negative or greater than string's length
- startIndex is greater than endIndex
Example 1: Java substring() Without End Index
class Main {
public static void main(String[] args) {
String str1 = "program";
// from the first character to the end
System.out.println(str1.substring(0)); // program
// from the 4th character to the end
System.out.println(str1.substring(3)); // gram
}
}
Example 2: Java substring() With End Index
class Main {
public static void main(String[] args) {
String str1 = "program";
// from 1st to the 7th character
System.out.println(str1.substring(0, 7)); // program
// from 1st to the 5th character
System.out.println(str1.substring(0, 5)); // progr
// from 4th to the 5th character
System.out.println(str1.substring(3, 5)); // gr
}
}
If you need to find the index of the first occurrence of the specified substring from a given string, use the Java String indexOf().