Minor improvements (#217)

* Add Eclipse project files to .gitignore

Signed-off-by: Marcono1234 <[email protected]>

* Minor clean up and documentation improvements

Signed-off-by: Marcono1234 <[email protected]>

* Store AbstractThreadLocalContext logger in static field

Signed-off-by: Marcono1234 <[email protected]>

.gitignore

@@ -1,5 +1,4 @@
-# Build / maven artifacts
-*.class
+# Build / Maven artifacts
 target/
 pom.xml.versionsBackup
 
@@ -11,10 +10,14 @@ pom.xml.versionsBackup
 *.war
 *.ear
 
-# virtual machine crash logs, see https://www.java.com/en/download/help/error_hotspot.html
+# Virtual machine crash logs, see https://www.java.com/en/download/help/error_hotspot.html
 hs_err_pid*
 
 # IntelliJ project files
 .idea/
 *.iml
 
+# Eclipse project files
+.settings/
+.classpath
+.project

.mvn/javadoc/package-list

@@ -10,6 +10,7 @@ nl.talsmasoftware.context.futures
 nl.talsmasoftware.context.metrics
 nl.talsmasoftware.context.locale
 nl.talsmasoftware.context.mdc
+nl.talsmasoftware.context.slf4j.mdc
 nl.talsmasoftware.context.opentracing
 nl.talsmasoftware.context.servletrequest
 nl.talsmasoftware.context.springsecurity

context-propagation/src/main/java/nl/talsmasoftware/context/ContextManager.java

@@ -35,6 +35,7 @@
  * and {@linkplain ContextManagers#onDeactivate(Class, Object, Object)} methods
  * to notify the appropriate context observers.
  *
+ * @param <T> type of the context value
  * @author Sjoerd Talsma
  */
 public interface ContextManager<T> {
@@ -46,7 +47,7 @@ public interface ContextManager<T> {
      *
      * @param value The value to initialize a new context for.
      * @return The new <em>active</em> context containing the specified value
-     * which should be closed by the caller at the end of its lifecycle.
+     * which should be closed by the caller at the end of its lifecycle from the same thread.
      */
     Context<T> initializeNewContext(T value);
 

context-propagation/src/main/java/nl/talsmasoftware/context/ContextSnapshot.java

@@ -49,7 +49,7 @@ public interface ContextSnapshot {
      * Using the {@linkplain nl.talsmasoftware.context.executors.ContextAwareExecutorService ContextAwareExecutorService}
      * is a safe way to propagate context snapshots without having to worry about closing them.
      *
-     * @return A new reactivationcontext with the snapshot values that will be valid until closed
+     * @return A new reactivation context with the snapshot values that will be valid until closed
      * (or new values are registered).
      */
     Context<Void> reactivate();

context-propagation/src/main/java/nl/talsmasoftware/context/clearable/Clearable.java

@@ -16,7 +16,7 @@
 package nl.talsmasoftware.context.clearable;
 
 /**
- * Interface that marks an to be 'clearable'.
+ * Interface that marks an object to be 'clearable'.
  * <p>
  * Context managers that support clearing the active context for the current thread
  * should implement the {@link Clearable} interface.
@@ -26,6 +26,7 @@
  * This operation is intended to only be used when re-using threads (e.g. when returning them to a thread-pool).
  *
  * @author Sjoerd Talsma
+ * @see ClearableContextManager
  */
 public interface Clearable {
 

context-propagation/src/main/java/nl/talsmasoftware/context/delegation/CallMappingExecutorService.java

@@ -55,6 +55,7 @@ protected CallMappingExecutorService(ExecutorService delegate) {
      * @return The mapped callable object.
      * @see #map(Callable)
      */
+    @Override
     protected final <V> Callable<V> wrap(Callable<V> callable) {
         return map(callable);
     }

context-propagation/src/main/java/nl/talsmasoftware/context/executors/ContextAwareExecutorService.java

@@ -39,7 +39,7 @@
  * @author Sjoerd Talsma
  */
 public class ContextAwareExecutorService extends CallMappingExecutorService {
-    private final Logger logger = Logger.getLogger(getClass().getName());
+    private static final Logger LOGGER = Logger.getLogger(ContextAwareExecutorService.class.getName());
 
     public ContextAwareExecutorService(ExecutorService delegate) {
         super(delegate);
@@ -77,12 +77,12 @@ public V call() throws Exception {
      * @param context   context to be closed
      * @param exception exception if any occurred
      */
-    private void tryClose(Context<?> context, Exception exception) throws Exception {
+    private static void tryClose(Context<?> context, Exception exception) throws Exception {
         if (context != null) try {
             context.close();
         } catch (RuntimeException closeEx) {
             if (exception != null) {
-                logger.log(Level.WARNING, "Exception closing context after failed operation: " + closeEx.getMessage(), closeEx);
+                LOGGER.log(Level.WARNING, "Exception closing context after failed operation: " + closeEx.getMessage(), closeEx);
                 throw exception;
             }
             throw closeEx;

context-propagation/src/main/java/nl/talsmasoftware/context/threadlocal/AbstractThreadLocalContext.java

@@ -34,6 +34,8 @@
  * @author Sjoerd Talsma
  */
 public abstract class AbstractThreadLocalContext<T> implements Context<T> {
+    private static final Logger LOGGER = Logger.getLogger(AbstractThreadLocalContext.class.getName());
+
     private static final AtomicBoolean DEPRECATED_CONSTRUCTOR_WARNING = new AtomicBoolean(true);
     /**
      * The constant of ThreadLocal context instances per subclass name so different types don't get mixed.
@@ -43,7 +45,6 @@ public abstract class AbstractThreadLocalContext<T> implements Context<T> {
 
     @SuppressWarnings("unchecked")
     private final ThreadLocal<AbstractThreadLocalContext<T>> sharedThreadLocalContext = threadLocalInstanceOf((Class) getClass());
-    private final Logger logger = Logger.getLogger(getClass().getName());
     private final AtomicBoolean closed = new AtomicBoolean(false);
     private final Class<? extends ContextManager<? super T>> contextManagerType;
 
@@ -73,7 +74,7 @@ public abstract class AbstractThreadLocalContext<T> implements Context<T> {
     @Deprecated
     protected AbstractThreadLocalContext(T newValue) {
         this(null, newValue);
-        logger.log(DEPRECATED_CONSTRUCTOR_WARNING.compareAndSet(true, false) ? Level.WARNING : Level.FINE,
+        LOGGER.log(DEPRECATED_CONSTRUCTOR_WARNING.compareAndSet(true, false) ? Level.WARNING : Level.FINE,
                 "Initialized new {0} without context manager type. " +
                         "This makes it impossible to register ContextObservers for it. " +
                         "Please fix {1} by specifying a ContextManager type " +
@@ -96,7 +97,7 @@ protected AbstractThreadLocalContext(Class<? extends ContextManager<? super T>>
         this.parentContext = sharedThreadLocalContext.get();
         this.value = newValue;
         this.sharedThreadLocalContext.set(this);
-        logger.log(Level.FINEST, "Initialized new {0}.", this);
+        LOGGER.log(Level.FINEST, "Initialized new {0}.", this);
         ContextManagers.onActivate(contextManagerType, value, parentContext == null ? null : parentContext.getValue());
     }
 
@@ -147,7 +148,7 @@ public T getValue() {
     public void close() {
         final boolean observe = closed.compareAndSet(false, true);
         final Context<T> restored = this.unwindIfNecessary(); // Remove this context created in the same thread.
-        logger.log(Level.FINEST, "Closed {0}.", this);
+        LOGGER.log(Level.FINEST, "Closed {0}.", this);
         if (observe) {
             ContextManagers.onDeactivate(contextManagerType, this.value, restored == null ? null : restored.getValue());
         }
@@ -159,6 +160,7 @@ public void close() {
      *
      * @return String representing this context class and either the current value or the fact that it was closed.
      */
+    @Override
     public String toString() {
         return getClass().getSimpleName() + (isClosed() ? "{closed}" : "{value=" + value + '}');
     }

readme.md

@@ -81,7 +81,7 @@ private static final ExecutorService THREADPOOL =
 The following `ThreadLocal`-based contexts are currently supported 
 out of the box by this context-propagation library:
 
-- [Slf4J MDC (Mapped Diagnostic Context)][mdc propagation]
+- [SLF4J MDC (Mapped Diagnostic Context)][slf4j mdc propagation]
 - [OpenTracing Span contexts][opentracing span propagation]
 - [Spring Security Context]
 - [Locale context][locale context]
@@ -167,14 +167,13 @@ configure various timers in the global default metric registry of your applicati
 
 
   [servletrequest propagation]: servletrequest-propagation
-  [mdc propagation]: slf4j-propagation
+  [slf4j mdc propagation]: slf4j-propagation
   [locale context]: locale-context
   [spring security context]: spring-security-context
   [opentracing span propagation]: opentracing-span-propagation
   [context propagation metrics]: context-propagation-metrics
   [context propagation micrometer]: context-propagation-micrometer
-  [default constructor]: https://en.wikipedia.org/wiki/Nullary_constructor
   [micrometer]: https://micrometer.io
 
-  [ContextAwareExecutorService]: https://javadoc.io/page/nl.talsmasoftware.context/context-propagation/latest/nl/talsmasoftware/context/executors/ContextAwareExecutorService.html
+  [ContextAwareExecutorService]: https://javadoc.io/doc/nl.talsmasoftware.context/context-propagation/latest/nl/talsmasoftware/context/executors/ContextAwareExecutorService.html
   [ContextAwareCompletableFuture]: context-propagation-java8#contextawarecompletablefuture

slf4j-propagation/README.md

@@ -1,10 +1,10 @@
 [![Maven Version][maven-img]][maven] 
 
-# Slf4J MDC propagation library
+# SLF4J MDC propagation library
 
 Adding the `slf4j-propagation` jar to your classpath
-is all that is needed to let the [Mapped Diagnostic Context (MDC)][MDC] 
-from the [Simple Logging Facade for Java (SLF4J)][Slf4J] 
+is all that is needed to let the [Mapped Diagnostic Context (MDC)][mdc] 
+from the [Simple Logging Facade for Java (SLF4J)][slf4j] 
 be automatically included into the `ContextSnapshot`.
 
 ## How to use this library

slf4j-propagation/src/main/java/nl/talsmasoftware/context/slf4j/mdc/Slf4jMdcManager.java

@@ -25,9 +25,9 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
- * Manager to propagate the {@link MDC} content from one thread to another.
+ * Manager to propagate the SLF4J {@link MDC} content from one thread to another.
  * <p>
- * As {@link MDC} already manages its own threadlocal state,
+ * As {@link MDC} already manages its own thread-local state,
  * getting the active context is 100% delegated to the MDC.<br>
  * This means that closing the resulting context from {@link #getActiveContext()} will have no side-effects,
  * as it is not ours to manage.

slf4j-propagation/src/main/java/nl/talsmasoftware/context/slf4j/mdc/package-info.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 /**
- * Propagate the {@link org.slf4j.MDC Slf4J MDC} content from one thread to another.
+ * Propagate the {@linkplain org.slf4j.MDC SLF4J MDC} content from one thread to another.
  *
  * <p>
  * This context manager maintains no threadlocal state of its own,

slf4j-propagation/src/main/resources/META-INF/services/nl.talsmasoftware.context.ContextManager

@@ -1 +1 @@
-nl.talsmasoftware.context.slf4j.mdc.Slf4jMdcManager
+nl.talsmasoftware.context.slf4j.mdc.Slf4jMdcManager

slf4j-propagation/src/test/java/nl/talsmasoftware/context/slf4j/mdc/Slf4jMdcManagerTest.java

@@ -52,7 +52,6 @@ public void setupThreadpool() {
     @AfterEach
     public void shutdownThreadpool() {
         threadpool.shutdown();
-        threadpool = null;
     }
 
     @BeforeEach
@@ -112,7 +111,6 @@ public void testSlf4jMdcContextToString() {
 
     @Test
     public void testClearActiveContexts() {
-        Slf4jMdcManager mgr = new Slf4jMdcManager();
         MDC.put("dummy", "value");
         // Test no-op for MdcManager
         ContextManagers.clearActiveContexts();