minor code improvements

agent/agent-bootstrap/src/main/java/com/microsoft/applicationinsights/agent/bootstrap/AzureFunctions.java

@@ -3,6 +3,7 @@
 
 package com.microsoft.applicationinsights.agent.bootstrap;
 
+import java.util.Optional;
 import java.util.function.Supplier;
 import javax.annotation.Nullable;
 
@@ -21,12 +22,14 @@ public static boolean hasConnectionString() {
   }
 
   public static void configureOnce() {
-    if (configure != null) {
-      if (!hasConnectionString()) {
-        configure.run();
-      }
-      configure = null;
-    }
+    Optional.ofNullable(configure)
+            .ifPresent(result ->{
+              if (!hasConnectionString()) 
+              {
+                result.run();
+              }  
+              result=null;
+            });
   }
 
   private AzureFunctions() {}

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/configuration/Configuration.java

@@ -21,6 +21,7 @@
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -1294,7 +1295,7 @@ public void validate() {
                   + " action. "
                   + "Learn more about attribute processors here: https://go.microsoft.com/fwlink/?linkid=2151557");
         }
-        extractAttribute.validate();
+        Optional.ofNullable(extractAttribute).ifPresent(ExtractAttribute::validate);
       }
 
       if (action == ProcessorActionType.MASK) {

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/init/FirstEntryPoint.java

@@ -79,9 +79,11 @@ public void init(EarlyInitAgentConfig earlyConfig) {
       if (DEBUG_SIGNED_JAR_ACCESS) {
         JarVerifierClassFileTransformer transformer = new JarVerifierClassFileTransformer();
         Instrumentation instrumentation = InstrumentationHolder.getInstrumentation();
-        instrumentation.addTransformer(transformer, true);
-        instrumentation.retransformClasses(Class.forName("java.util.jar.JarVerifier"));
-        instrumentation.removeTransformer(transformer);
+        if(instrumentation != null) {
+          instrumentation.addTransformer(transformer, true);
+          instrumentation.retransformClasses(Class.forName("java.util.jar.JarVerifier"));
+          instrumentation.removeTransformer(transformer);
+        }
       }
       Path agentPath = javaagentFile.toPath();
       // need to initialize version before initializing DiagnosticsHelper
@@ -109,27 +111,26 @@ public void init(EarlyInitAgentConfig earlyConfig) {
       }
 
       checkTlsConnectionsToVirtualServersEnabled();
-
       if (startupLogger.isDebugEnabled()) {
         startupLogger.debug(
-            "Input arguments: " + ManagementFactory.getRuntimeMXBean().getInputArguments());
-        startupLogger.debug("_JAVA_OPTIONS: " + System.getenv("_JAVA_OPTIONS"));
-        startupLogger.debug("JAVA_TOOL_OPTIONS: " + System.getenv("JAVA_TOOL_OPTIONS"));
+            "Input arguments: {} " , ManagementFactory.getRuntimeMXBean().getInputArguments());
+        startupLogger.debug("_JAVA_OPTIONS: {}" , System.getenv("_JAVA_OPTIONS"));
+        startupLogger.debug("JAVA_TOOL_OPTIONS: {}" , System.getenv("JAVA_TOOL_OPTIONS"));
       }
 
       if (startupLogger.isTraceEnabled()) {
-        startupLogger.trace("OS: " + System.getProperty("os.name"));
-        startupLogger.trace("Classpath: " + System.getProperty("java.class.path"));
-        startupLogger.trace("Netty versions: " + NettyVersions.extract());
-        startupLogger.trace("Env: " + System.getenv());
-        startupLogger.trace("System properties: " + findSystemProperties());
+        startupLogger.trace("OS: {}" , System.getProperty("os.name"));
+        startupLogger.trace("Classpath: {}" , System.getProperty("java.class.path"));
+        startupLogger.trace("Netty versions: {} " , NettyVersions.extract());
+        startupLogger.trace("Env: {}" , System.getenv());
+        startupLogger.trace("System properties: {} " , findSystemProperties());
       }
 
       if (startupLogger.isTraceEnabled()) {
         AppInsightsCertificate appInsightsCertificate = new AppInsightsCertificate(startupLogger);
         startupLogger.trace(
-            "Application Insights root certificate in the Java keystore: "
-                + appInsightsCertificate.isInJavaKeystore());
+            "Application Insights root certificate in the Java keystore: {}"
+                , appInsightsCertificate.isInJavaKeystore());
       }
 
     } catch (Exception e) {

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/logbackpatch/FixedWindowRollingPolicy.java

@@ -29,6 +29,8 @@
 import ch.qos.logback.core.rolling.helper.RenameUtil;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
 import java.util.Date;
 
 // copied from ch.qos.logback.core.rolling.FixedWindowRollingPolicy
@@ -145,7 +147,11 @@ public void rollover() throws RolloverFailure {
       File file = new File(fileNamePattern.convertInt(maxIndex));
 
       if (file.exists()) {
-        file.delete();
+        try {
+          Files.delete(file.toPath());
+        } catch (IOException e) {
+         addError("File deletaion failed.",e);
+        }
       }
 
       // Map {(maxIndex - 1), ..., minIndex} to {maxIndex, ..., minIndex+1}

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/profiler/Profiler.java

@@ -21,9 +21,11 @@
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.lang.management.ManagementFactory;
+import java.nio.file.Files;
 import java.time.Duration;
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
+import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ScheduledExecutorService;
@@ -91,12 +93,13 @@ public Profiler(Configuration.ProfilerConfiguration config, File tempDir) {
    * Call init before run.
    *
    * @throws IOException Trouble communicating with MBean server
+   * @throws JfrStreamingException
    * @throws InstanceNotFoundException The JVM does not support JFR, or experimental option is not
    *     enabled.
    */
   public void initialize(
-      UploadService uploadService, ScheduledExecutorService scheduledExecutorService)
-      throws Exception {
+      UploadService uploadService, ScheduledExecutorService scheduledExecutorService) throws IOException, InstanceNotFoundException, JfrStreamingException
+       {
     this.uploadService = uploadService;
     this.scheduledExecutorService = scheduledExecutorService;
 
@@ -267,10 +270,13 @@ private static void closeRecording(Recording recording, File recordingFile) {
   private static void writeFileFromStream(Recording recording, File recordingFile)
       throws IOException, JfrStreamingException {
     if (recordingFile.exists()) {
-      recordingFile.delete();
+      Files.delete(recordingFile.toPath());
     }
-    recordingFile.createNewFile();
 
+    if(!recordingFile.createNewFile()){
+      logger.error("File creation failed");
+    }
+
     try (BufferedInputStream stream = new BufferedInputStream(recording.getStream(null, null));
         FileOutputStream fos = new FileOutputStream(recordingFile)) {
       int read;
@@ -284,13 +290,16 @@ private static void writeFileFromStream(Recording recording, File recordingFile)
   private void clearActiveRecording() {
     synchronized (activeRecordingLock) {
       activeRecording = null;
-
-      // delete uploaded profile
-      if (activeRecordingFile != null && activeRecordingFile.exists()) {
-        if (!activeRecordingFile.delete()) {
-          logger.error("Failed to remove file " + activeRecordingFile.getAbsolutePath());
+      Optional.of(activeRecordingFile).ifPresent(result -> {
+        if(result.exists()) {
+           try {
+            Files.delete(result.toPath());
+          } catch (IOException e) {
+            logger.error("Failed to remove file {}" , result.getAbsolutePath());
+          }
         }
-      }
+      });
+
       activeRecordingFile = null;
     }
   }