how to cut a certion part from a string in java

To cut a portion of a string in Java, you can use the substring method of the String class.

The substring method takes two arguments: a start index and an end index. It returns a new string that is a substring of the original string, starting at the specified start index and ending at the specified end index. The original string is not modified.

For example, consider the following string:

String str = "Hello, world!";

To cut the substring "Hello" from this string, you can use the substring method as follows:

String substring = str.substring(0, 5);

This will create a new string that is a substring of str, starting at index 0 (the first character) and ending at index 5 (the character before the space). The resulting string will be "Hello".

To cut the substring "world!" from this string, you can use the substring method as follows:

String substring = str.substring(7);

This will create a new string that is a substring of str, starting at index 7 (the character after the space) and ending at the end of the string. The resulting string will be "world!".

Note that the substring method is zero-based, meaning that the first character of the string is at index 0, the second character is at index 1, and so on.

Here's an example of a complete program that cuts a portion of a string using the substring method:

public class Main {
   public static void main(String[] args) {
      String str = "Hello, world!";
      String substring = str.substring(7);
      System.out.println(substring);  // Output: "world!"
   }
}

This will print "world!" to the console.