Java中的多个同时子串替换

时间:2018-06-19 05:18:47

标签: java string stringbuilder

(我来自蟒蛇世界,所以如果我将一些术语用于常规的话,我会道歉。)

我有StringList的起始/结束索引要替换。没有太多细节,请考虑这个基本的模型:

String text = "my email is foo@bar.com and my number is (213)-XXX-XXXX"
List<Token> findings = SomeModule.someFnc(text);

并且Token具有

的定义
class Token {
    int start, end;
    String type;
}

List代表我尝试编辑的敏感数据的开始和结束位置。

实际上,API返回我迭代的数据以获取:

[{ "start" : 12, "end" : 22, "type" : "EMAIL_ADDRESS" }, { "start" : 41, "end" : 54, "type" : "PHONE_NUMBER" }]

使用这些数据,我的最终目标是在这些text对象指定的Token中编辑令牌以获取此值:

"my email is [EMAIL_ADDRESS] and my number is [PHONE_NUMBER]"

使这个问题变得非常重要的是,替换子串的长度与它们所替换的子串的长度不一样。

我目前的行动计划是从StringBuilder构建text,按照起始索引的相反顺序对这些ID进行排序,然后从缓冲区的右端替换。

但有些东西告诉我应该有更好的方法......有吗?

3 个答案:

答案 0 :(得分:9)

这种方法有效:

import java.util.ArrayList;
import java.util.List;

public class Test {
    public static void main(String[] args) {
        String text = "my email is foo@bar.com and my number is (213)-XXX-XXXX";

        List<Token> findings = new ArrayList<>();
        findings.add(new Token(12, 22, "EMAIL_ADDRESS"));
        findings.add(new Token(41, 54, "PHONE_NUMBER"));

        System.out.println(replace(text, findings));
    }

    public static String replace(String text, List<Token> findings) {
        int position = 0;
        StringBuilder result = new StringBuilder();

        for (Token finding : findings) {
            result.append(text.substring(position, finding.start));
            result.append('[').append(finding.type).append(']');

            position = finding.end + 1;
        }

        return result.append(text.substring(position)).toString();
    }
}

class Token {
    int start, end;
    String type;

    Token(int start, int end, String type) {
        this.start = start;
        this.end = end;
        this.type = type;
    }
}

输出:

my email is [EMAIL_ADDRESS] and my number is [PHONE_NUMBER]

答案 1 :(得分:3)

确保所有令牌均按start索引以升序排序:

List<Token> tokens = new ArrayList<>();
tokens.sort(Comparator.comparing(Token::getStart));

现在,您可以替换从输入文本末尾开始的所有字符串:

public String replace(String text, List<Token> tokens) {
    StringBuilder sb = new StringBuilder(text);
    for (int i = tokens.size() - 1; i >= 0; i--) {
        Token token = tokens.get(i);
        sb.replace(token.start, token.end + 1, "[" + token.type + "]");
    }
    return sb.toString();
}

答案 2 :(得分:1)

从开始和结束之间提取子字符串,然后按它进行拆分。然后你得到一个包含2个元素的数组,插入你想要的内容。接下来你必须移动你的下一个字符串&#39;通过(您替换长度的前一个字符串)和(放置在其位置的字符串)之间的差异来替换ID。

代码(根据情况,令牌中的&#39; end&#39;是独占的):

public class Main {

    public static void main(String... args) {
        String text = "I want to replace AAA and B and scary wombat";
        Token[] tokens = {new Token(18, 21, "TEST"), new Token(26, 27, "TEST"), new Token(32, 44, "TEST")};
        int delta = 0;
        for (Token token : tokens) {
            String splitter = text.substring(token.start + delta, token.end + delta);
            System.out.println("Splitter: " + splitter);
            delta += token.replacement.length() - splitter.length();
            String[] beforeAndAfter = text.split(Pattern.quote(splitter));
            text = beforeAndAfter[0] + token.replacement + 
                    (beforeAndAfter.length == 2 ? beforeAndAfter[1] : ""); // in case where there are no more chars after splitter in text
        }
        System.out.println(text);
    }

    static class Token {
        public final int start, end;
        public final String replacement;

        public Token(int start, int end, String replacement) {
            this.start = start;
            this.end = end;
            this.replacement = replacement;
        }
    }
}