Java remove multiple characters from string

Question

I'm playing with string manipulation and I would like to do something like this, when a user types the lesson name: Windows Server, the program should remove Windows plus white space character and display only Server. I managed to do this using this code:

  Scanner in = new Scanner(System.in);

    String lesson;

    System.out.println("Input lesson name: ");

    lesson = in.nextLine();

    String newLesson = lesson.replaceAll("Windows\\s+", "");

    System.out.println("New Lesson is " + newLesson);

But now I want to remove multiple characters like Linux and Unix. How would I include in my regex Linux and Unix?

If the user would type in Linux Administration, the program should display Administration only.

Answer 1

To remove only the first word your regex would ^\\w+\\s

This says:

1. ^ match from the start of the string only
2. \\w+ Find 1 or more non-whitespace characters, do not be greedy so stop as soon as you find a match for
3. \\s a whitespace character".

Answer 2

If I understood the question, try:

String newLesson = lesson.replaceAll("(Windows|Linux|Unix)\\s+", "");

Output:

Input lesson name: 
Linux Administration
Administration

Answer 3

You have two options here...

1. Create a Regex term that encompasses all the terms you want to remove, I think something like the below would do it (but I'm no Regex expert).

    replaceAll("(Windows|Linux|Unix)\\\\s+", ""); 

2. Store the words you want to remove in a list then cycle through it, removing each term.

    List<String> terms = new ArrayList<>(Arrays.asList{"Windows\\\\s+", "Linux\\\\s+", "Unix\\\\s+"}); for(String term : terms) { lesson = lesson.replaceAll(term, ""); } 

Answer 4

由于您只想删除第一个单词，并假设空格是定界符，因此可以在不使用正则表达式的情况下进行操作：

String newLesson = lesson.substring(lesson.indexOf(" ") + 1);