1

我正在尝试提取文本文件中每一行中存在的端到端延迟值。我使用正则表达式仅获取每行末尾的数字，但我得到了正则表达式的错误，即：

非法转义字符

此外，我需要打开文件以获取每一行并提取末端延迟值并将其存储在另一个文本文件中（所有提取的末端延迟）。

这是我的代码：

import java.awt.Desktop;
import java.io.File;
import java.io.IOException;
import javax.swing.filechooser.FileSystemView;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author DevAdmin
 */
public class extarctor {

    public static final String s_example = "sender id: 116/sequence number: 117/depth: 443/sending time: 4/23/2020 2:08:54 AM/data: Hello I am SN: 116 this is event # 117 from my sideEnd-End Delay is:2.74550137092987E-05delay registered @ Sink: 621.932901880787";

    public static void main(String[] args) throws IOException {
        //text file, should be opening in default text editor
        File file = new File(FileSystemView.getFileSystemView().getHomeDirectory().getAbsolutePath()+ "/res/End-End-Delay.txt");

        //first check if Desktop is supported by Platform or not
        if(!Desktop.isDesktopSupported()){
            System.out.println("Desktop is not supported");
            return;
        }

        Desktop desktop = Desktop.getDesktop();
        if(file.exists()) System.out.println("Good, keep going!");

        System.out.println(s_example.matches("\d+\.\d+$"));



    }


}
4

1 回答 1

1

用于Matcher::group提取所需的数字。

演示：

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

public class Main {
    public static void main(String[] args) {
        String s_example = "sender id: 116/sequence number: 117/depth: 443/sending time: 4/23/2020 2:08:54 AM/data: Hello I am SN: 116 this is event # 117 from my sideEnd-End Delay is:2.74550137092987E-05delay registered @ Sink: 621.932901880787";

        Pattern pattern = Pattern.compile("\\d+.\\d+$");
        Matcher matcher = pattern.matcher(s_example);
        while (matcher.find()) {
            System.out.println(matcher.group());
        }
    }
}

输出：

621.932901880787
于 2020-05-08T00:38:10.537 回答