替换Strings

Question

我有一个函数来检查某个单词是否出现在一个特定的行中，然后用一个给定的字符包围它们。

上面的代码工作起来很有魅力，但是由于字符串数组中的单词“word”总是小写，所以单词也是小写的。我怎样才能解决这个问题？

投入：

BufferedReader in = "Hello, my name is John:";
char c = '*';
String [] words = {"hello","john"}; 

期望的输出：

BufferedWriter out = "*Hello*, my name is *John*:";

实际产出：

BufferedWriter out = "*hello*, my name is *john*";

守则：

public void replaceString(BufferedReader in, BufferedWriter out, char c, String[] words){

String line_in = in.readLine();

    while (line_in != null) {
        for (int j = 0; j < words.length; j++) {

            line_in = line_in.replaceAll("(?i)" + words[j], bold + words[j]
                    + bold);

        }

        out.write(line_in);
        out.newLine();
        line_in = in.readLine();

    }
}

Answer 1

使用

line_in.replaceAll("(?i)(" + words[j] + ")", bold + "$1" + bold);
//                      \________________/           \/
//                         capture word          reference it