Apache FTPClientでのコマンドのトレース

package test;

import java.io.IOException;

import org.apache.commons.net.ProtocolCommandEvent;
import org.apache.commons.net.ProtocolCommandListener;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class FTPCommandTraceTest {

	private static final String FTP_SERVER = "192.168.220.3";
	private static final String FTP_USER_NAME = "valuser";
	private static final String FTP_USER_PASS = "valuser";

	private static Logger logger = LoggerFactory.getLogger(FTPCommandTraceTest.class);

	public static void main(String[] args) throws IOException {

		FTPClient client = new FTPClient();
		client.addProtocolCommandListener(new ExampleCommandListener());

		// FTPサーバ操作例
		client.connect(FTP_SERVER);
		client.login(FTP_USER_NAME, FTP_USER_PASS);
		for (FTPFile file : client.listFiles(".")) {
			logger.debug("name={}", file.getName());
		}
		client.quit();
		client.disconnect();
	}

}

class ExampleCommandListener implements ProtocolCommandListener {

	private static Logger logger = LoggerFactory.getLogger(ExampleCommandListener.class);

	public void protocolCommandSent(ProtocolCommandEvent event) {
		logger.trace("> " + event.getCommand());
	}

	public void protocolReplyReceived(ProtocolCommandEvent event) {
		StringBuilder sb = new StringBuilder();
		logger.trace("< " + event.getMessage());
	}

}

<project xmlns="http://maven.apache.org/POM/4.0.0"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>test</groupId>
	<artifactId>ftp-example</artifactId>
	<version>1.0.0</version>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<maven.compiler.source>1.8</maven.compiler.source>
		<maven.compiler.target>1.8</maven.compiler.target>
	</properties>

	<dependencies>

		<!-- FTP -->
		<dependency>
			<groupId>commons-net</groupId>
			<artifactId>commons-net</artifactId>
			<version>3.6</version>
		</dependency>

		<!-- Logging -->
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-api</artifactId>
			<version>1.7.25</version>
		</dependency>
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-simple</artifactId>
			<version>1.7.25</version>
		</dependency>

	</dependencies>

</project>

# SLF4J's SimpleLogger configuration file
# Simple implementation of Logger that sends all enabled log messages, for all defined loggers, to System.err.

# Default logging detail level for all instances of SimpleLogger.
# Must be one of ("trace", "debug", "info", "warn", or "error").
# If not specified, defaults to "info".
#org.slf4j.simpleLogger.defaultLogLevel=info
org.slf4j.simpleLogger.defaultLogLevel=trace

# Logging detail level for a SimpleLogger instance named "xxxxx".
# Must be one of ("trace", "debug", "info", "warn", or "error").
# If not specified, the default logging detail level is used.
#org.slf4j.simpleLogger.log.xxxxx=
#org.slf4j.simpleLogger.log.test.FTPCommandTraceTest=trace

# Set to true if you want the current date and time to be included in output messages.
# Default is false, and will output the number of milliseconds elapsed since startup.
#org.slf4j.simpleLogger.showDateTime=false
org.slf4j.simpleLogger.showDateTime=true

# The date and time format to be used in the output messages.
# The pattern describing the date and time format is the same that is used in java.text.SimpleDateFormat.
# If the format is not specified or is invalid, the default format is used.
# The default format is yyyy-MM-dd HH:mm:ss:SSS Z.
#org.slf4j.simpleLogger.dateTimeFormat=yyyy-MM-dd HH:mm:ss:SSS Z
org.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss:SSS Z

# Set to true if you want to output the current thread name.
# Defaults to true.
#org.slf4j.simpleLogger.showThreadName=true

# Set to true if you want the Logger instance name to be included in output messages.
# Defaults to true.
#org.slf4j.simpleLogger.showLogName=true

# Set to true if you want the last component of the name to be included in output messages.
# Defaults to false.
#org.slf4j.simpleLogger.showShortLogName=false