Java Taking Strings Apart with Substrings - Web Development and Design | Tutorial for Java, PHP, HTML, Javascript Java Taking Strings Apart with Substrings - Web Development and Design | Tutorial for Java, PHP, HTML, Javascript

Breaking

Post Top Ad

Post Top Ad

Wednesday, December 26, 2018

Java Taking Strings Apart with Substrings

Java Taking Strings Apart with Substrings

Problem 

You want to break a string apart into substrings by position. 

Solution 

Use the String object’s substring( ) method. 

Explained

The substring( ) method constructs a new String object made up of a run of characters contained somewhere in the original string, the one whose substring( ) you called. The name of this method, substring( ), violates the stylistic dictum that words should be capitalized; if Java were 100.0% consistent, this method would be named subString. But it’s not—it’s substring. The substring method is overloaded: both forms require a starting index. The one-argument form returns from startIndex to the end. The two-argument form takes an ending index (not a length, as in some languages), so that an index can be generated by the String methods indexOf( ) or lastIndexOf( ). Note that the end index is one beyond the last character!

// File SubStringDemo.java
public static void main(String[] av) {
 String a = "Java is great.";
 System.out.println(a);
 String b = a.substring(5); // b is the String "is great."
 System.out.println(b);
 String c = a.substring(5,7);// c is the String "is"
 System.out.println(c);
 String d = a.substring(5,a.length( ));// d is "is great."
 System.out.println(d);
}

When run, this prints the following:

> java SubStringDemo
Java is great.
is great.
is
is great.
>

No comments:

Post a Comment

Post Top Ad