find a substring in a string java
package hello;
public class SubStringProblem {
public static void main(String[] args) {
// 1st example - You can use the indexOf() method to check if
// a String contains another substring in Java
// if it does then indexOf() will return the starting index of
// that substring, otherwise it will return -1
System.out
.println("Checking if one String contains another String using indexOf() in Java");
String input = "Java is the best programming language";
boolean isPresent = input.indexOf("Java") != -1 ? true : false;
if (isPresent) {
System.out.println("input string: " + input);
System.out.println("search string: " + "Java");
System.out.println("does String contains substring? " + "YES");
}
// indexOf is case-sensitive so if you pass wrong case, you will get wrong
// result
System.out.println("Doing search with different case");
isPresent = input.indexOf("java") != -1 ? true : false;
System.out.println("isPresent: " + isPresent); // false because indeOf() is
// case-sensitive
// 2nd example - You can also use the contains() method to check if
// a String contains another String in Java or not. This method
// returns a boolean, true if substring is found on String, or false
// otherwise.
// if you need boolean use this method rather than indexOf()
System.out
.println("Checking if one String contains another String using contains() in Java");
input = "C++ is predecessor of Java";
boolean isFound = input.contains("Java");
if (isFound) {
System.out.println("input string: " + input);
System.out.println("search string: " + "Java");
System.out.println("does substring is found inside String? " + "YES");
}
// contains is also case-sensitive
System.out.println("Searching with different case");
isFound = input.contains("java");
System.out.println("isFound: " + isFound); // false because indeOf() is
// case-sensitive
}
}
Output
Checking if one String contains another String using indexOf() in Java
input string: Java is the best programming language
search string: Java
does String contain substring? YES
Doing search with different case
isPresent: false
Checking if one String contains another String using contains() in Java
input string: C++ is the predecessor of Java
search string: Java
does substring is found inside String? YES
Searching for different case
isFound: false