Provide more control for how log messages are viewed in an application

qupath · Sep 18, 2023 · ddf1726 · ddf1726
1 parent 1d32ad3
commit ddf1726
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Showing 14 changed files with 370 additions and 62 deletions.
diff --git a/logviewer-api/src/main/java/qupath/ui/logviewer/api/listener/LoggerListener.java b/logviewer-api/src/main/java/qupath/ui/logviewer/api/listener/LoggerListener.java
@@ -1,10 +1,6 @@
 package qupath.ui.logviewer.api.listener;
 
 import qupath.ui.logviewer.api.LogMessage;
-import qupath.ui.logviewer.api.manager.LoggerManager;
-
-import java.util.Optional;
-import java.util.ServiceLoader;
 
 /**
  * Interface for classes that listen to new log messages.
@@ -18,22 +14,4 @@ public interface LoggerListener {
      * @param logMessage  the new log message
      */
     void addLogMessage(LogMessage logMessage);
-
-    /**
-     * Get the logger manager chosen by SLF4J.
-     * This method shouldn't need to be overridden.
-     *
-     * @return the logger manager chosen by SLF4J or an empty optional if no logger has been found
-     */
-    default Optional<LoggerManager> getCurrentLoggerManager() {
-        ServiceLoader<LoggerManager> serviceLoader = ServiceLoader.load(LoggerManager.class);
-
-        for (LoggerManager loggerManager : serviceLoader) {
-            if (loggerManager.isFrameworkActive()) {
-                return Optional.of(loggerManager);
-            }
-        }
-
-        return Optional.empty();
-    }
 }
diff --git a/logviewer-api/src/main/java/qupath/ui/logviewer/api/manager/LoggerManager.java b/logviewer-api/src/main/java/qupath/ui/logviewer/api/manager/LoggerManager.java
@@ -4,6 +4,9 @@
 import qupath.ui.logviewer.api.listener.LoggerListener;
 import org.slf4j.event.Level;
 
+import java.util.Optional;
+import java.util.ServiceLoader;
+
 /**
  * Interface for logging frameworks.
  */
@@ -17,6 +20,13 @@ public interface LoggerManager {
      */
     void addListener(LoggerListener listener);
 
+    /**
+     * Stop forwarding log messages to the provided logger listener.
+     *
+     * @param listener  the listener which will stop receiving the logged messages
+     */
+    void removeListener(LoggerListener listener);
+
     /**
      * Set the log level of the root logger.
      *
@@ -37,4 +47,21 @@ public interface LoggerManager {
      * @return true if this logging framework is used by SLF4J
      */
     boolean isFrameworkActive();
+
+    /**
+     * Get the logger manager chosen by SLF4J.
+     *
+     * @return the logger manager chosen by SLF4J or an empty optional if no logger has been found
+     */
+    static Optional<LoggerManager> getCurrentLoggerManager() {
+        ServiceLoader<LoggerManager> serviceLoader = ServiceLoader.load(LoggerManager.class);
+
+        for (LoggerManager loggerManager : serviceLoader) {
+            if (loggerManager.isFrameworkActive()) {
+                return Optional.of(loggerManager);
+            }
+        }
+
+        return Optional.empty();
+    }
 }
diff --git a/logviewer-logging-jdk/src/main/java/qupath/ui/logviewer/logging/jdk/JdkManager.java b/logviewer-logging-jdk/src/main/java/qupath/ui/logviewer/logging/jdk/JdkManager.java
@@ -6,6 +6,9 @@
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
 
+import java.util.HashMap;
+import java.util.Map;
+import java.util.logging.Handler;
 import java.util.logging.Logger;
 
 /**
@@ -14,10 +17,23 @@
 public class JdkManager implements LoggerManager {
 
     private static final Logger rootLogger = Logger.getLogger("");
+    private static final Map<LoggerListener, Handler> handlers = new HashMap<>();
 
     @Override
     public void addListener(LoggerListener listener) {
-        rootLogger.addHandler(new JdkHandler(listener));
+        if (!handlers.containsKey(listener)) {
+            Handler handler = new JdkHandler(listener);
+            handlers.put(listener, handler);
+            rootLogger.addHandler(handler);
+        }
+    }
+
+    @Override
+    public void removeListener(LoggerListener listener) {
+        if (handlers.containsKey(listener)) {
+            Handler handler = handlers.remove(listener);
+            rootLogger.removeHandler(handler);
+        }
     }
 
     @Override

diff --git a/logviewer-logging-jdk/src/test/java/qupath/ui/logviewer/logging/jdk/TestJdkManager.java b/logviewer-logging-jdk/src/test/java/qupath/ui/logviewer/logging/jdk/TestJdkManager.java
@@ -7,6 +7,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
+import qupath.ui.logviewer.api.listener.LoggerListener;
 
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
@@ -60,6 +61,20 @@ void Check_Message_Forwarded() throws InterruptedException {
         assertTrue(latch.await(100, TimeUnit.MILLISECONDS));
     }
 
+    @Test
+    void Check_Message_Not_Forwarded() throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(1);
+        JdkManager jdkManager = new JdkManager();
+        LoggerListener loggerListener = logMessage -> latch.countDown();
+        jdkManager.addListener(loggerListener);
+        jdkManager.setRootLogLevel(Level.TRACE);
+        jdkManager.removeListener(loggerListener);
+
+        slf4jLogger.info("A log message");
+
+        assertFalse(latch.await(100, TimeUnit.MILLISECONDS));
+    }
+
     @Test
     void Check_N_Message_Forwarded() throws InterruptedException {
         int N = 5;

diff --git a/...wer-logging-logback/src/main/java/qupath/ui/logviewer/logging/logback/LogbackManager.java b/...wer-logging-logback/src/main/java/qupath/ui/logviewer/logging/logback/LogbackManager.java
@@ -1,30 +1,47 @@
 package qupath.ui.logviewer.logging.logback;
 
 import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Appender;
 import qupath.ui.logviewer.api.listener.LoggerListener;
 import qupath.ui.logviewer.api.manager.LoggerManager;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * Manager setting up and managing the Logback logger.
  */
 public class LogbackManager implements LoggerManager {
 
     private static final Logger slf4jLogger = LoggerFactory.getLogger(LogbackManager.class);
     private static final ch.qos.logback.classic.Logger logbackRootLogger = getRootLogger();
+    private static final Map<LoggerListener, Appender<ILoggingEvent>> appenders = new HashMap<>();
 
     @Override
     public void addListener(LoggerListener listener) {
-        if (logbackRootLogger != null) {
-            var appender = new LogbackAppender(listener);
-            appender.setName("LogViewer");
-            appender.setContext(logbackRootLogger.getLoggerContext());
-            appender.start();
-            logbackRootLogger.addAppender(appender);
-        } else {
-            slf4jLogger.warn("Cannot add appender to root logger using logback!");
+        if (!appenders.containsKey(listener)) {
+            if (logbackRootLogger != null) {
+                Appender<ILoggingEvent> appender = new LogbackAppender(listener);
+                appender.setName("LogViewer");
+                appender.setContext(logbackRootLogger.getLoggerContext());
+                appender.start();
+                appenders.put(listener, appender);
+                logbackRootLogger.addAppender(appender);
+            } else {
+                slf4jLogger.warn("Cannot add appender to root logger using logback!");
+            }
+        }
+    }
+
+    @Override
+    public void removeListener(LoggerListener listener) {
+        if (logbackRootLogger != null && appenders.containsKey(listener)) {
+            Appender<ILoggingEvent> appender = appenders.remove(listener);
+            logbackRootLogger.detachAppender(appender);
         }
     }
 

diff --git a/...logging-logback/src/test/java/qupath/ui/logviewer/logging/logback/TestLogbackManager.java b/...logging-logback/src/test/java/qupath/ui/logviewer/logging/logback/TestLogbackManager.java
@@ -7,6 +7,8 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
+import qupath.ui.logviewer.api.listener.LoggerListener;
+
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.IntStream;
@@ -60,6 +62,20 @@ void Check_Message_Forwarded() throws InterruptedException {
         assertTrue(latch.await(100, TimeUnit.MILLISECONDS));
     }
 
+    @Test
+    void Check_Message_Not_Forwarded() throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(1);
+        LogbackManager logbackManager = new LogbackManager();
+        LoggerListener loggerListener = logMessage -> latch.countDown();
+        logbackManager.addListener(loggerListener);
+        logbackManager.setRootLogLevel(Level.TRACE);
+        logbackManager.removeListener(loggerListener);
+
+        slf4jLogger.info("A log message");
+
+        assertFalse(latch.await(100, TimeUnit.MILLISECONDS));
+    }
+
     @Test
     void Check_N_Message_Forwarded() throws InterruptedException {
         int N = 5;

diff --git a/...-logging-reload4j/src/main/java/qupath/ui/logviewer/logging/reload4j/Reload4jManager.java b/...-logging-reload4j/src/main/java/qupath/ui/logviewer/logging/reload4j/Reload4jManager.java
@@ -1,24 +1,40 @@
 package qupath.ui.logviewer.logging.reload4j;
 
+import org.apache.log4j.Appender;
 import qupath.ui.logviewer.api.listener.LoggerListener;
 import qupath.ui.logviewer.api.manager.LoggerManager;
 import org.apache.log4j.Logger;
 import org.slf4j.ILoggerFactory;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * Manager setting up and managing the Reload4j logger.
  */
 public class Reload4jManager implements LoggerManager {
 
     private static final Logger rootLogger = Logger.getRootLogger();
+    private static final Map<LoggerListener, Appender> appenders = new HashMap<>();
 
     @Override
     public void addListener(LoggerListener listener) {
-        var appender = new Reload4jAppender(listener);
-        appender.setName("LogViewer");
-        rootLogger.addAppender(appender);
+        if (!appenders.containsKey(listener)) {
+            Appender appender = new Reload4jAppender(listener);
+            appender.setName("LogViewer");
+            appenders.put(listener, appender);
+            rootLogger.addAppender(appender);
+        }
+    }
+
+    @Override
+    public void removeListener(LoggerListener listener) {
+        if (appenders.containsKey(listener)) {
+            Appender appender = appenders.remove(listener);
+            rootLogger.removeAppender(appender);
+        }
     }
 
     @Override

diff --git a/...ging-reload4j/src/test/java/qupath/ui/logviewer/logging/reload4j/TestReload4jManager.java b/...ging-reload4j/src/test/java/qupath/ui/logviewer/logging/reload4j/TestReload4jManager.java
@@ -7,6 +7,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
+import qupath.ui.logviewer.api.listener.LoggerListener;
 
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
@@ -60,6 +61,20 @@ void Check_Message_Forwarded() throws InterruptedException {
         assertTrue(latch.await(100, TimeUnit.MILLISECONDS));
     }
 
+    @Test
+    void Check_Message_Not_Forwarded() throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(1);
+        Reload4jManager reload4jManager = new Reload4jManager();
+        LoggerListener loggerListener = logMessage -> latch.countDown();
+        reload4jManager.addListener(loggerListener);
+        reload4jManager.setRootLogLevel(Level.TRACE);
+        reload4jManager.removeListener(loggerListener);
+
+        slf4jLogger.info("A log message");
+
+        assertFalse(latch.await(100, TimeUnit.MILLISECONDS));
+    }
+
     @Test
     void Check_N_Message_Forwarded() throws InterruptedException {
         int N = 5;

diff --git a/logviewer-ui-main/src/main/java/qupath/ui/logviewer/ui/main/LogMessageCounts.java b/logviewer-ui-main/src/main/java/qupath/ui/logviewer/ui/main/LogMessageCounts.java
@@ -10,7 +10,7 @@
 /**
  * Counts the number of LogMessage of each level of an <a href="https://docs.oracle.com/javase/8/javafx/api/javafx/collections/ObservableList.html">ObservableList</a>.
  */
-class LogMessageCounts {
+public class LogMessageCounts {
 
     private final ReadOnlyIntegerWrapper allMessagesCount = new ReadOnlyIntegerWrapper(0);
     private final ReadOnlyIntegerWrapper errorLevelCount = new ReadOnlyIntegerWrapper(0);