Java正则表达式打印字

Question

我想打印包含模式_fact的单词。例如，在下面的字符串中要打印agg_day_adv_campaign_demand_fact。

String text =
  "FROM dt_dim AS d, "+
  "adj_dim AS adj " +
  "cam_dim AS cam, " +
  "agg_day_adv_campaign_demand_fact AS fact ";

Answer 1

regex \ w * _fact会做到这一点。 您可以在此处测试此正则表达式（http://regexpal.com/）

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {

    public static void main(String[] args) {
        String text    =
                "FROM dt_dim AS d, "+
                        "adj_dim AS adj " +
                        "cam_dim AS cam, " +
                        "agg_day_adv_campaign_demand_fact AS fact ";
        Pattern pattern = Pattern.compile("\\w*_fact");
        Matcher matcher = pattern.matcher(text);
        while (matcher.find()) {
            System.out.println("Found the text " + matcher.group()+  "starting at " + matcher.start()
                    + " index and ending at index " + matcher.end());
            System.out.println(text.substring(matcher.start(), matcher.end()));
        }
    }
}

Answer 2

您可以简单地将split字符串转换为单词并逐个检查单词以搜索您的模式。

Answer 3

    String text =
              "FROM dt_dim AS d, "+
              "adj_dim AS adj " +
              "cam_dim AS cam, " +
              "agg_day_adv_campaign_demand_fact AS fact ";

    Pattern FACT_PAT = Pattern.compile("(\\S+_fact)");
    Matcher m = FACT_PAT.matcher(text);
    if (m.find()){
        System.out.println(m.group(1));
    }