用 Java 解析日志文件
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Parsing a log file in Java
提问by user454894
All,
全部，
I have a log file with the below content.
我有一个包含以下内容的日志文件。
Request from Centercord.
2010-12-14 12:42:13.724 [ 6796] ****************************
2010-12-14 12:42:13.724 [ 6796] 1111111111111111
2010-12-14 12:42:13.724 [ 6796]22222222222
Response from Centercord.
2010-12-14 12:42:21.802 [ 5960] 11111111111111
2010-12-14 12:42:21.802 [ 5960] ffffffffffffffffffffffffffff
2010-12-14 12:42:21.802 [ 5960] tttttttttttttttttttttttttttt
Request from Centercord.
2010-12-14 12:42:13.724 [ 6796] ****************************
I need to create two log files one is for storing all the Request details and the other one is for storing all the Response details. How can I parse this and prepare two log files?.
我需要创建两个日志文件，一个用于存储所有请求详细信息，另一个用于存储所有响应详细信息。我如何解析它并准备两个日志文件？。
I need the below answer.
我需要以下答案。
Log 1:
Request from Centercord.
2010-12-14 12:42:13.724 [ 6796] ****************************
2010-12-14 12:42:13.724 [ 6796] 1111111111111111
2010-12-14 12:42:13.724 [ 6796]22222222222
2010-12-14 12:42:13.724 [ 6796] ****************************
Log 2:
Response from Centercord.
2010-12-14 12:42:21.802 [ 5960] 11111111111111
2010-12-14 12:42:21.802 [ 5960] ffffffffffffffffffffffffffff
2010-12-14 12:42:21.802 [ 5960] tttttttttttttttttttttttttttt
Regards, Kanagaraj
问候， 卡纳加拉吉
回答by aioobe
Here is how I would do it:
这是我将如何做到的：
import java.io.*;
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
try {
PrintWriter requests = new PrintWriter("requests.txt");
PrintWriter responses = new PrintWriter("responses.txt");
PrintWriter currentLog = null;
Scanner s = new Scanner(new File("log.txt"));
while (s.hasNextLine()) {
String line = s.nextLine();
if (line.startsWith("Request from"))
currentLog = requests;
else if (line.startsWith("Response from"))
currentLog = responses;
else if (currentLog != null)
currentLog.println(line);
}
requests.close();
responses.close();
s.close();
} catch (IOException ioex) {
// handle exception...
}
}
}
Given log.txt
给定日志.txt
Request from Centercord.
2010-12-14 12:42:13.724 [ 6796] ****************************
2010-12-14 12:42:13.724 [ 6796] 1111111111111111
2010-12-14 12:42:13.724 [ 6796]22222222222
Response from Centercord.
2010-12-14 12:42:21.802 [ 5960] 11111111111111
2010-12-14 12:42:21.802 [ 5960] ffffffffffffffffffffffffffff
2010-12-14 12:42:21.802 [ 5960] tttttttttttttttttttttttttttt
Request from Centercord.
2010-12-14 12:42:13.724 [ 6796] ****************************
It produces, requests.txt
它产生，requests.txt
2010-12-14 12:42:13.724 [ 6796] ****************************
2010-12-14 12:42:13.724 [ 6796] 1111111111111111
2010-12-14 12:42:13.724 [ 6796]22222222222
2010-12-14 12:42:13.724 [ 6796] ****************************
...and responses.txt
...和响应.txt
2010-12-14 12:42:21.802 [ 5960] 11111111111111
2010-12-14 12:42:21.802 [ 5960] ffffffffffffffffffffffffffff
2010-12-14 12:42:21.802 [ 5960] tttttttttttttttttttttttttttt
回答by iuiz
You can use regular expressions or RandomAccessFiles to get the data in the way you want.
您可以使用正则表达式或 RandomAccessFiles 以您想要的方式获取数据。
回答by Andreas Dolk
StringBuilder requestBuilder = new StringBuilder("Request from Centercord.\n");
StringBuilder responseBuilder = new StringBuilder("Response from Centercord.\n");
boolean isResponse = false;
for (String line:getLinesFromLogFile()) {
if (line.startsWith("Response")) {
if(isResponse)
responseBuilder.append("\n");
isResponse = true;
} else if (line.startsWith("Request")) {
if(!isResponse)
requestBuilder.append("\n");
isResponse = false;
} else {
if (isResponse) {
responseBuilder.append(line).append("\n");
} else {
requestBuilder.append(line).append("\n");
}
}
}
Now dump the contents of both StringBuilders to the target files.
现在将两个 StringBuilder 的内容转储到目标文件。
回答by darioo
For reducing boilerplate code, download Google Guavaand use this code:
要减少样板代码，请下载Google Guava并使用以下代码：
File inputFile = new File("input.log");
File outputLog1 = new File("log1.log");
File outputLog2 = new File("log2.log");
String match1 = "[ 6796]";
String match2 = "[ 5960]";
Files.append("Request from Centercord.\n", outputLog1, Charsets.UTF_8);
Files.append("Response from Centercord.\n", outputLog2, Charsets.UTF_8);
List<String> lines = Files.readLines(inputFile, Charsets.UTF_8);
for (String line : lines) {
if(line.contains(match1)) Files.append(line + "\n", outputLog1, Charsets.UTF_8);
if(line.contains(match2)) Files.append(line + "\n", outputLog2, Charsets.UTF_8);
}
