Replace in Java 20

To replace a substring within a string in Java, you can use the replace or replaceAll methods from the String class. Here are some examples:

Example 1: Using replace method

String str = "I love Java programming";

String substr = "Java";

String newSubstr = "Python";

String newStr = str.replace(substr, newSubstr);

System.out.println(newStr);

In this example, we have used the replace method to replace the substring "Java" with "Python" in the original string "I love Java programming". The method returns a new string with the replacement. Note that the replace method replaces all occurrences of the substring.

Example 2: Using replaceAll method

String str = "I love Java programming";

String regex = "\\s+"; // regular expression to match one or more spaces

String newStr = str.replaceAll(regex, "-");

System.out.println(newStr);

In this example, we have used the replaceAll method to replace all spaces in the original string "I love Java programming" with hyphens ("-"). Note that the replaceAll method takes a regular expression as the first argument to match the substring to be replaced. Since we want to replace all spaces, we have used the regular expression "\\s+" which matches one or more spaces.