package testutil; import java.util.logging.*; public class LoggingConfig { public LoggingConfig() { try { // Load a properties file from class path that way can't be achieved with java.util.logging.config.file /* final LogManager logManager = LogManager.getLogManager(); try (final InputStream is = getClass().getResourceAsStream("/logging.properties")) { logManager.readConfiguration(is); } */ // Programmatic configuration System.setProperty("java.util.logging.SimpleFormatter.format", "%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS.%1$tL %4$-7s [%3$s] (%2$s) %5$s %6$s%n"); final ConsoleHandler consoleHandler = new ConsoleHandler(); consoleHandler.setLevel(Level.FINEST); consoleHandler.setFormatter(new SimpleFormatter()); final Logger app = Logger.getLogger("app"); app.setLevel(Level.FINEST); app.addHandler(consoleHandler); } catch (Exception e) { // The runtime won't show stack traces if the exception is thrown e.printStackTrace(); } } }
java.util.logging: Programmatic configuration and logging with Java8 lambdas
TweetPosted on Monday Mar 30, 2015 at 06:24PM in Technology
Configuration
We can put configurations in following places (ordered by priority):
-
java.util.logging.config.class
system property. specify FQCN of a class here -
java.util.logging.config.file
system property. specify the path to a property file here -
$JAVA_HOME/lib/logging.properties
file. put JRE-wide configuration here
Use of java.util.logging.config.class
is most flexible. in that way we can simply put a config class under src/test/java
for unit tests. we need to put configuration procedures in the default constructor. an implementation would be something like following:
If you prefer configuration in a property file rather than a config class, following will work as the same to config class:
handlers=java.util.logging.ConsoleHandler java.util.logging.ConsoleHandler.formatter=java.util.logging.SimpleFormatter java.util.logging.SimpleFormatter.format=%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS.%1$tL %4$-7s [%3$s] (%2$s) %5$s %6$s%n java.util.logging.ConsoleHandler.level=FINEST app.level=FINEST
To set system property for every test execution, put following plugin
definition to your pom.xml
. note that IntelliJ IDEA respects this configuration in its test execution.
<plugin> <artifactId>maven-surefire-plugin</artifactId> <version>2.18.1</version> <configuration> <systemPropertyVariables> <java.util.logging.config.class> testutil.LoggingConfig </java.util.logging.config.class> <!-- If you prefer a file this will work too --> <!--<java.util.logging.config.file>--> <!--src/test/resources/logging.properties--> <!--</java.util.logging.config.file>--> </systemPropertyVariables> </configuration> </plugin>
Logging examples
Application class:
public class MyClass { private static final Logger log = Logger.getLogger(MyClass.class.getName()); public String hello(String greetings, String name) { // entering will be logged as FINER log.entering(MyClass.class.getName(), "hello", new Object[]{greetings, name}); // lambdas log.finest(() -> "finest: " + LocalDateTime.now()); log.finer(() -> "finer: " + LocalDateTime.now()); log.fine(() -> "fine: " + LocalDateTime.now()); log.info(() -> "info: " + LocalDateTime.now()); log.warning(() -> "warning: " + LocalDateTime.now()); log.severe(() -> "severe: " + LocalDateTime.now()); // exception logging // throwing will be logged as FINER log.throwing(MyClass.class.getName(), "hello", new Exception("test")); // exception + message logging with lambda log.log(Level.FINEST, new Exception("test"), () -> String.format("arg=%s", name)); // exception + parameter logging with LogRecord final LogRecord record = new LogRecord(Level.FINEST, "arg={0}"); record.setThrown(new Exception("test")); record.setLoggerName(log.getName()); // logger name will be null unless this record.setParameters(new Object[]{name}); log.log(record); final String rc = greetings + ", " + name; // exiting will be logged as FINER log.exiting(MyClass.class.getName(), "hello", rc); return rc; } }
Test:
public class MyClassTest { @org.junit.Test public void testHello() throws Exception { MyClass sut = new MyClass(); Assert.assertEquals("Hello, Kyle", sut.hello("Hello", "Kyle")); } }
Output:
2015-03-30 18:01:19.362 FINER [app.MyClass] (app.MyClass hello) ENTRY Hello Kyle 2015-03-30 18:01:19.425 FINEST [app.MyClass] (app.MyClass hello) finest: 2015-03-30T18:01:19.425 2015-03-30 18:01:19.427 FINER [app.MyClass] (app.MyClass hello) finer: 2015-03-30T18:01:19.427 2015-03-30 18:01:19.428 FINE [app.MyClass] (app.MyClass hello) fine: 2015-03-30T18:01:19.428 2015-03-30 18:01:19.429 INFO [app.MyClass] (app.MyClass hello) info: 2015-03-30T18:01:19.429 2015-03-30 18:01:19.431 WARNING [app.MyClass] (app.MyClass hello) warning: 2015-03-30T18:01:19.430 2015-03-30 18:01:19.433 SEVERE [app.MyClass] (app.MyClass hello) severe: 2015-03-30T18:01:19.433 2015-03-30 18:01:19.434 FINER [app.MyClass] (app.MyClass hello) THROW java.lang.Exception: test at app.MyClass.hello(MyClass.java:27) at app.MyClassTest.testHello(MyClassTest.java:10) ... 2015-03-30 18:01:19.439 FINEST [app.MyClass] (app.MyClass hello) arg=Kyle java.lang.Exception: test at app.MyClass.hello(MyClass.java:30) at app.MyClassTest.testHello(MyClassTest.java:10) ... 2015-03-30 18:01:19.442 FINEST [app.MyClass] (app.MyClass hello) arg=Kyle java.lang.Exception: test at app.MyClass.hello(MyClass.java:34) at app.MyClassTest.testHello(MyClassTest.java:10) ... 2015-03-30 18:01:19.447 FINER [app.MyClass] (app.MyClass hello) RETURN Hello, Kyle
Tags: logging
How can i use the LoggingConfig class when I am executing the program also, i don't want it to be restricted only for testing mode
Posted by senthil on August 24, 2017 at 12:11 PM JST #