PropertyConfigurator in log4j2

Question

I'm migrating log4j 1.2.8 to log4j 2.3. Everything works fine, beside that I'm not finding any any alternative for the PropertyConfigurator.

Is there another class to take care of what the PropertyConfigurator did before?

Infield

Did any of the solutions below solve your problem? – Thrave

Answer 1

Maybe this can help you?

How do I reconfigure log4j2 in code with a specific configuration file? See the below example. Be aware that this LoggerContext class is not part of the public API so your code may break with any minor release.

// import org.apache.logging.log4j.core.LoggerContext;

LoggerContext context = (org.apache.logging.log4j.core.LoggerContext) LogManager.getContext(false);
File file = new File("path/to/a/different/log4j2.xml");


// this will force a reconfiguration
context.setConfigLocation(file.toURI());**

Messinger

this works well in log4j2 2.16.0 – Terri

Answer 2

My solution consisted simply in following the instructions in the Log4J site https://logging.apache.org/log4j/2.x/manual/migration.html, that is, I replaced

<dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.17</version>
</dependency>

with

 <dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-1.2-api</artifactId>
    <version>2.14.1</version>
 </dependency>

No compilation error, even with class org.apache.log4j.PropertyConfigurator.

This was easier than attempting to migrate to

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-core</artifactId>
    <version>2.14.1</version>
</dependency>

which, as pointed out by @Christian, has no replacement for class PropertyConfigurator. Admittedly, by not migrating I won't benefit from the new capabilities of Log4j 2.

Rost

No compilation error, but what did the calls to that class do at runtime? Your use of PropertyConfigurator still has the same results as it did in log4j 1.x? – Cristen

this solution is no longer valid since the security issue – Sufferable

Answer 3

Log4j 2 currently supports configuration with XML, JSON or YAML. While properties files may also be supported in the near future the syntax will certainly be different from Log4j 1.

Heirloom

Answer 4

Here my solution to the same problem:

web.xml

<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

    <context-param>
        <param-name>isLog4jContextSelectorNamed</param-name>
        <param-value>false</param-value>
    </context-param>

    <!-- ... and so on -->

</web-app>

LoggerHelper.java

    import java.io.File;
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.core.LoggerContext;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;

    public final class LoggerHelper {

      public static Logger INSTANCE;

      public static void initialize() {    
        String        fileName = "<PATH>/log4j.xml";
        LoggerContext context  = (LoggerContext)LogManager.getContext(false);

        context.setConfigLocation(new File(fileName).toURI());
        INSTANCE = LoggerFactory.getLogger(LoggerHelper.class);

        String logMessage = String.format("Initialized (%s).", fileName);
        System.out.println(logMessage);
        INSTANCE.info(logMessage);
      }

    }

Siloxane

Answer 5

If you want to change some properties in the log4j2.properties file and make it effect immediatly. Here is the method:

    private static void changeSomeProperties(String pathToPropertiesFile) {

    File log4j2PropertiesFile= new File(pathToPropertiesFile, "log4j2.properties");
    Properties properties = new Properties();
    try (FileInputStream fileInputStream = new FileInputStream(log4j2PropertiesFile);
        BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream)) {
        properties.load(bufferedInputStream);
    } catch (Exception e) {
        //handle exception
    }

    properties.setProperty("property.logDirectory", "someLogPath");
    File updatedLog4j2PropertiesFile = new File(pathToPropertiesFile, "updatedlog4j2.properties");

    try (OutputStream output = new FileOutputStream(updatedLog4j2PropertiesFile)) {
        properties.store(output, null);
    } catch (IOException e) {
        //handle exception
    }

    LoggerContext loggerContext = LoggerContext.getContext(false);
loggerContext.setConfigLocation(updatedLog4j2PropertiesFile.toURI());
    loggerContext.reconfigure();
}

Scriptwriter

Answer 6

The first line before any log4j2 code - configure sys prop to your Properties configuration factory

System.setProperty("log4j.configurationFactory", ThePropertiesConfigurationFactory.class.getName());

@Plugin(name = "ThePropertiesConfigurationFactory", category = ConfigurationFactory.CATEGORY)
@Order(8)
public class ThePropertiesConfigurationFactory extends ConfigurationFactory {
    @Override
    protected String[] getSupportedTypes() {
        return new String[]{".properties", "*"};
    }
    

    @Override
    public PropertiesConfiguration getConfiguration(final LoggerContext loggerContext, final ConfigurationSource source) {
            final Properties properties = new Properties();
            
            try (final InputStream configStream = source.getInputStream()) {
                //load config 
                properties.load(configStream);
                //var loggersProperties = readPropertiesInFormatLog4j1AndTransformInLog4j2Properties();
                //properties.putAll(loggersProperties);
            } catch (final IOException ioe) {
                throw new ConfigurationException("Unable to load " + source.toString(), ioe);
            }
            
            return new PropertiesConfigurationBuilder()
                    .setConfigurationSource(source)
                    .setRootProperties(properties)
                    .setLoggerContext(loggerContext)
                    .build();
    }
}

Or extend PropertiesConfigurationFactory

Lexy

Answer 7

No need of PropertyConfigurator in log4j2. 
It will automatically read your log4j2.property file.
    
Just make sure you have below jar included in your pom.
    
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-api</artifactId>
                <version>2.17.2</version>
            </dependency>
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-core</artifactId>
                <version>2.17.2</version>
            </dependency>
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-slf4j-impl</artifactId>
                <version>2.17.2</version>
            </dependency>
           <dependency>
               <groupId>org.slf4j</groupId>
               <artifactId>slf4j-api</artifactId>
               <version>1.7.36</version>
           </dependency>
    
    ----------------------------------------------------------------------
    log4j2.properties
    
    appenders=xyz
    appender.xyz.type = Console
    appender.xyz.name = myOutput
    appender.xyz.layout.type = PatternLayout
    appender.xyz.layout.pattern = [%d{yy-MMM-dd HH:mm:ss:S}] [%p] [%c{1}:%L] - %m%n
    rootLogger.level = info
    rootLogger.appenderRefs = abc
    rootLogger.appenderRef.abc.ref = myOutputstrong text
    
    ----------------------------------------------------------------------
    MyClass.java
    
        import org.slf4j.Logger;
        import org.slf4j.LoggerFactory;
        
        public class MyClass {
        
            public static void main(String[] args) {
        
                Logger logger = LoggerFactory.getLogger(MyClass.class);
                logger.info("----start-------");
        
            }
        }
    
    ----------------------------------------------------------------------
    
    Output:
    
        [22-Jul-22 17:11:09:128] [INFO] [MyClass:24] - ----start-------

• Reconfigure

If you want to reconfigure log4j2 in code with a specific configuration file use below code.

// import org.apache.logging.log4j.core.LoggerContext;

LoggerContext context = (org.apache.logging.log4j.core.LoggerContext) LogManager.getContext(false);
File file = new File("path/to/a/different/log4j2.xml");

// this will force a reconfiguration
context.setConfigLocation(file.toURI());

Expanse