![]() ![]() To get what you're trying to do with lastSubstring(), you can efficiently use substring(). You can't efficiently find the last index with a given value using indexOf(), so lastIndexOf() is necessary. You can check out this tutorial to find out more about String processing using Apache Commons Lang API. I'm not aware of that sort of counterpart to substring(), but it's not really necessary. ![]() StringUtils.substringBefore(text, " was born")) The separator isn’t returned: assertEquals("Julia Evans", The one-argument variant of substring will return the string starting from the argument up to the end: String whatIActuallySay whatIShouldSay.substring (3) Note that the convention of using negative indices to count from the back of some sequence is almost never used in Java (never in the core libraries, as far as I know and very rarely. Similarly, the substringBefore method gets the substring before the first occurrence of a separator. StringUtils.substringAfter(text, "living in ")) The separator isn’t returned: assertEquals("the USA (United States of America).", The substringAfter method from the same class gets the substring after the first occurrence of a separator. There is a simplified version of this method in case the substring is nested in between two instances of the same String: substringBetween(String str, String tag) StringUtils.substringBetween(text, "(", ")")) In this example, we’re going to see how to extract a substring nested between two Strings: assertEquals("United States of America", ![]() It is used to return the substring that comes after the first occurrence of the given. Apache Commons Lang provides a host of helper utilities for the java.lang API, most notably String manipulation methods. The substringAfter() method is a static method of StringUtils. Now I want to remove that appended string on pressing back button. String str '123dance456' String substr 'dance' String parts str.split(substr) String before parts0 String after parts1 It is noteworthy that the second answer not work if we have more than one occurrence of the substring. ![]() It always pays to pay attention to these little edge cases.The Apache Commons libraries add some useful methods for manipulating core Java types. In my application, I am appending a string to create path to generate a URL. otherwise, default to the empty string (or some other value) if the substring does occur within the string, set the values accordinglyĪfter = str.substring(position + substr.length()) String str '123dance456' String substr 'dance' String parts str. To make the first answer more efficient - as it is my preferred answer - then, we would need to remember the position of the substring: final int position = str.indexOf(substr) As such, I would much rather the first solution, since it works irrespective of the composition of the original substring. Also, since split will interpret its input as a regular expression we have to be wary of invalid regular expression syntax. Which ensures that the returned array has at most two elements. To that end, if we only want the first one to be recognized, it would be safer to call split with a limit: String parts = str.split(substr, 2) It is noteworthy that the second answer not work if we have more than one occurrence of the substring. String after = str.substring(str.indexOf(substr) + substr.length()) The arguments say that the substring starts at the 9th character of the string and that its length is 10 characters. String before = str.substring(0, str.indexOf(substr)) SELECT SUBSTRING('This is the first substring example', 9, 10) AS substringextraction This means: I want to find a substring from the text ‘This is the first substring example’. You can do this: String str = "123dance456" ![]()
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