java - 如何循环遍历字符串并删除特定元素？

Question

所以，如果我有这样的内容:“我的消息需要检查”。

我有一个字符串:[1][3][4]。这些是我想要删除的消息元素(例如“my”将是元素 1，“that”将是元素 3)。

我如何循环遍历此消息并删除另一个字符串中的元素？

示例:

String messageToFilter = "my message that needs checking";
String filter = "[1]-[3]-[4]";

for (String curElement : filter.split("-")) {
    //If I remove element [0], element [3] is then moved to [2]; so not sure what to do!
}

//So at this stage I need the messageToFilter, but with the elements from filter removed.
//In the example above this would output 'message checking'.

Answer 1

首先，您需要从过滤器中获取整数索引，然后删除句子中该位置的单词。

    String messageToFilter = "my message that needs checking";
    // Split into an array of words
    String[] words = messageToFilter.split("\\s+");

    // get the indexes
    Pattern pat = Pattern.compile("(\\d+)");
    Matcher mat = pat.matcher("[1]-[3]-[4]");
    while (mat.find()) {
        int index = Integer.parseInt(mat.group());
        // set the matching word to null (assuming the indexes start at 1)
        words[index-1] = null;
    }
    // Rebuild the message
    StringBuilder messageFiltered = new StringBuilder();
    for (String w : words) {
        if (w != null) {
            messageFiltered.append(w).append(" ");
        }
    }
    System.out.println(messageFiltered.toString());

输出:

message checking