Question

所以我有一个日志文件，我需要搜索某些字符串并打印出属于某些日期范围的行。

我已经完成了第一部分，但我坚持第二部分。我如何在特定日期内打印出一个字符串。所以说我想在2012-09-01和2012-09-15之间打印所有字符串

日志示例：

 2012-09-13 16:04:22 DEBUG SID:34523 BID:1329 RID:65d33 'Starting new session'
 2012-09-13 16:04:30 DEBUG SID:34523 BID:1329 RID:54f22 'Authenticating User'
 2012-09-13 16:05:30 DEBUG SID:42111 BID:319 RID:65a23 'Starting new session'
 2012-09-13 16:04:50 ERROR SID:34523 BID:1329 RID:54ff3 'Missing Authentication token'
 2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:86472 'Authenticating User'
 2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:7a323 'Deleting asset with ID 543234'
 2012-09-13 16:05:32 WARN SID:42111 BID:319 RID:7a323 'Invalid asset ID'

到目前为止，这是我的代码：

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Date;
import java.util.Scanner;


public class ReadLogs {

   public static void main(String args[]) throws FileNotFoundException{
       String line, logString ="";
       Date startDate, endDate;

       ArrayList<String> logList = new ArrayList<>();

       Scanner logScanner = new Scanner(new        File("C:\\Users\\cmccarth\\Desktop\\logs.txt"));
       while (logScanner.hasNextLine()) {
            line = logScanner.nextLine();
            logList.add(line);                  
        }

       for (String z : logList) {
//          System.out.println(z);
        }


      // This function prints out all lines containing a specific string

       for( int i = 0; i <= logList.size() - 1; i++)
       {
           logString = logList.get(i);
           if(logString.contains("16:04:22")){
               System.out.println("String Contains" +logString);
           }

       }
   }     
}

Answer 1

执行以下步骤：

1）创建2个Date对象，其中包含您要搜索的日期范围（使用简单日期格式获取这些日期）：

 Date lowerRange; 
 Date upperRange;

2）现在循环遍历已过滤的日志列表并确认从日志文件中获取的字符串，然后将日期作为标记[0]。

String[] tokens = logString.split(" ");
String dateStr = tokens[0];

// Convert this date to String using Simple Date Format
Date date = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH).parse(dateStr);

3）现在，您可以将此日期与您必须查看的2个日期进行比较。

if(date > lowerRange && date < upperRange)
{
  // this is the date you wanted...process the log file entry
}

请参阅以下SO帖子，了解字符串到日期的转换：String-to-date

Answer 2

试试这个示例代码。

正在使用Calendar，SimpleDateFormat和Pattern。

Calendar：与时间参数一起形成开始日期和结束日期
SimpleDateFormat：将字符串解析为日期对象
Pattern：从日志中获取特定的日期模式

以下是代码：

   String[] logs = new String[] {

            "2012-09-13 16:04:22 DEBUG SID:34523 BID:1329 RID:65d33 'Starting new session'",
            "2012-09-13 16:04:30 DEBUG SID:34523 BID:1329 RID:54f22 'Authenticating User'",
            "2012-09-13 16:05:30 DEBUG SID:42111 BID:319 RID:65a23 'Starting new session'",
            "2012-09-13 16:04:50 ERROR SID:34523 BID:1329 RID:54ff3 'Missing Authentication token'",
            "2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:86472 'Authenticating User'",
            "2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:7a323 'Deleting asset with ID 543234'",
            "2012-09-13 16:05:32 WARN SID:42111 BID:319 RID:7a323 'Invalid asset ID'" };

    List<String> logList = new ArrayList<String>();
    for (String log : logs) {
        logList.add(log);
    }

    Calendar cal = Calendar.getInstance();
    cal.set(Calendar.YEAR, 2012);
    cal.set(Calendar.MONTH, 8);
    cal.set(Calendar.DATE, 13);
    cal.set(Calendar.HOUR_OF_DAY, 16);
    cal.set(Calendar.MINUTE, 4);
    cal.set(Calendar.SECOND, 30);
    cal.set(Calendar.MILLISECOND, 0);

    Date startDate = cal.getTime();

    cal.set(Calendar.MINUTE, 5);
    cal.set(Calendar.SECOND, 31);

    Date endDate = cal.getTime();

    SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

    Pattern pattern = Pattern.compile("^(\\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2})");

    Matcher matcher = null;
    String logString = null;
    Date date = null;
    for (int i = 0; i < logList.size(); i++) {
        logString = logList.get(i);
        matcher = pattern.matcher(logString);

        if (matcher.find()) {
            try {
                date = format.parse(matcher.group());
                if (date.getTime() >= startDate.getTime()
                        && date.getTime() <= endDate.getTime()) {
                    System.out.println(logString);
                }
            } catch (ParseException e) {
                e.printStackTrace();
            }
        }

    }

输出:(在2012-09-13 16:04:30和2012-09-13 16:05:31之间进行日志记录）

2012-09-13 16:04:30 DEBUG SID:34523 BID:1329 RID:54f22 'Authenticating User'
2012-09-13 16:05:30 DEBUG SID:42111 BID:319 RID:65a23 'Starting new session'
2012-09-13 16:04:50 ERROR SID:34523 BID:1329 RID:54ff3 'Missing Authentication token'
2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:86472 'Authenticating User'
2012-09-13 16:05:31 DEBUG SID:42111 BID:319 RID:7a323 'Deleting asset with ID 543234'

Answer 3

尝试一下（对我有用）

static void readdata(String startDate, String endDate) throws IOException, ParseException {
        String file = "your file location";
        List<String> logList = new ArrayList<String>();
        BufferedReader reader = new BufferedReader(new FileReader(file));
        String line = reader.readLine();
        while (line != null) {
            logList.add(line);
            // read next line
            line = reader.readLine();
        }
        reader.close();

        Pattern pattern = Pattern.compile("([12]\\d{3}-(0[1-9]|1[0-2])-(0[1-9]|[12]\\d|3[01]))");

        Matcher matcher = null;
        String logString = null;
        Date date = null;
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
        for (int i = 0; i < logList.size(); i++) {
            logString = logList.get(i);
            matcher = pattern.matcher(logString);
            if (matcher.find()) {
                date = format.parse(matcher.group());

                Date st = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH).parse(startDate);
                Date ed = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH).parse(endDate);

                int res = st.compareTo(date);

                if (res <= 0) {

                    if (logString.contains(startDate)) {
                        {
                            System.out.println(logString);
                        }
                        continue;
                    }
                    if (date.after(ed)) {
                        break;
                    }

                    System.out.println(logString);
                }

            }
        }
    }

如何在日志文件的某些日期之间打印出字符串

3 个答案: