What is log4j.properties file


The log4j.properties file is a log4j configuration file. Advantage of using log4j.properties file is that, if we make any change in java file we have to recompile it. But if we make any change in log4j.properties file then there is no need to compile.

Log4j.properties file keeps properties in key-value pairs. By default, the LogManager looks for a file named log4j.properties in the CLASSPATH.

 Project structure

























 App.java

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
package readPropertiesFile;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

//Java Properties File Example
// .ini or .properties file have same functionalities, only extension is different
// For these properties files to be read, it should be pasted directly in main project folder
public class App {
  public static void main(String[] args) {

    Properties prop = new Properties();
    InputStream readIni = null;
    InputStream readProperties = null;

    try {

        readIni = new FileInputStream("config.ini");
        readProperties = new FileInputStream("config.properties");

        // load .ini  file
        prop.load(readIni);
       
        // get the property value and print it out
        System.out.println(prop.getProperty("database"));
        System.out.println(prop.getProperty("dbuser"));
        System.out.println(prop.getProperty("dbpassword"));
       
        // load .properties  file
        prop.load(readProperties);
        String dbname=prop.getProperty("database"); // store in variable
        System.out.println("------dbname------"+dbname);       
        System.out.println(prop.getProperty("database"));
        System.out.println(prop.getProperty("dbuser"));
        System.out.println(prop.getProperty("dbpassword"));

    }
   
    catch (IOException ex) {
        ex.printStackTrace();
    }
   

  }
}


config.ini
1
2
3
4
#Fri Jan 17 22:37:45 MYT 2014
dbpassword=password_ini
database=localhost_ini
dbuser=mkyong_ini


config.properties

1
2
3
4
#Fri Jan 17 22:37:45 MYT 2014
dbpassword=password_properties
database=localhost_properties
dbuser=mkyong_properties



Output:
localhost_ini
mkyong_ini
password_ini
------dbname------localhost_properties
localhost_properties
mkyong_properties
password_properties

                                                        || NEXT TOPIC ||

                    



Related Article:

No comments :

Post a Comment