Provide more informative error message

assembly/assembly-wsmaster-war/src/main/java/org/eclipse/che/api/deploy/jsonrpc/CheMajorWebSocketEndpointExecutorServiceProvider.java

@@ -11,16 +11,21 @@
  */
 package org.eclipse.che.api.deploy.jsonrpc;
 
+import static org.slf4j.LoggerFactory.getLogger;
+
 import java.util.concurrent.ExecutorService;
 import javax.inject.Inject;
 import javax.inject.Named;
 import javax.inject.Singleton;
 import org.eclipse.che.commons.lang.execution.ExecutorServiceProvider;
+import org.slf4j.Logger;
 
 /** {@link ExecutorService} provider used in {@link CheMajorWebSocketEndpoint}. */
 @Singleton
 public class CheMajorWebSocketEndpointExecutorServiceProvider extends ExecutorServiceProvider {
 
+  private static final Logger LOG = getLogger(ExecutorServiceProvider.class);
+
   public static final String JSON_RPC_MAJOR_CORE_POOL_SIZE_PARAMETER_NAME =
       "che.core.jsonrpc.processor_core_pool_size";
   public static final String JSON_RPC_MAJOR_MAX_POOL_SIZE_PARAMETER_NAME =
@@ -33,6 +38,15 @@ public CheMajorWebSocketEndpointExecutorServiceProvider(
       @Named(JSON_RPC_MAJOR_CORE_POOL_SIZE_PARAMETER_NAME) int corePoolSize,
       @Named(JSON_RPC_MAJOR_MAX_POOL_SIZE_PARAMETER_NAME) int maxPoolSize,
       @Named(JSON_RPC_MAJOR_QUEUE_CAPACITY_PARAMETER_NAME) int queueCapacity) {
-    super(corePoolSize, maxPoolSize, queueCapacity);
+    super(
+        corePoolSize,
+        maxPoolSize,
+        queueCapacity,
+        (r, executor) ->
+            LOG.error(
+                "Executor on major websocket endpoint rejected to handle the payload {}. Some important messages may be lost. Consider increasing `{}`. Now it's configured to {}",
+                r,
+                JSON_RPC_MAJOR_QUEUE_CAPACITY_PARAMETER_NAME,
+                queueCapacity));
   }
 }

core/commons/che-core-commons-lang/src/main/java/org/eclipse/che/commons/lang/execution/ExecutorServiceProvider.java

@@ -17,6 +17,7 @@
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.ThreadPoolExecutor;
@@ -44,15 +45,18 @@ public class ExecutorServiceProvider implements Provider<ExecutorService> {
   private static final Logger LOG = getLogger(ExecutorServiceProvider.class);
 
   private final ThreadPoolExecutor executor;
-
   /**
    * @param corePoolSize - corePoolSize of ThreadPoolExecutor
    * @param maxPoolSize - maximumPoolSize of ThreadPoolExecutor
    * @param queueCapacity - queue capacity. if > 0 then this is capacity of {@link
    *     LinkedBlockingQueue} if <=0 then {@link SynchronousQueue} are used.
+   * @param rejectedExecutionHandler - {@link RejectedExecutionHandler} of ThreadPoolExecutor
    */
-  public ExecutorServiceProvider(int corePoolSize, int maxPoolSize, int queueCapacity) {
-
+  public ExecutorServiceProvider(
+      int corePoolSize,
+      int maxPoolSize,
+      int queueCapacity,
+      RejectedExecutionHandler rejectedExecutionHandler) {
     ThreadFactory factory =
         new ThreadFactoryBuilder()
             .setUncaughtExceptionHandler(LoggingUncaughtExceptionHandler.getInstance())
@@ -68,11 +72,24 @@ public ExecutorServiceProvider(int corePoolSize, int maxPoolSize, int queueCapac
             SECONDS,
             queueCapacity > 0 ? new LinkedBlockingQueue<>(queueCapacity) : new SynchronousQueue<>(),
             factory);
-    executor.setRejectedExecutionHandler(
-        (r, __) -> LOG.warn("Executor rejected to handle the payload {}", r));
+    executor.setRejectedExecutionHandler(rejectedExecutionHandler);
     executor.prestartCoreThread();
   }
 
+  /**
+   * @param corePoolSize - corePoolSize of ThreadPoolExecutor
+   * @param maxPoolSize - maximumPoolSize of ThreadPoolExecutor
+   * @param queueCapacity - queue capacity. if > 0 then this is capacity of {@link
+   *     LinkedBlockingQueue} if <=0 then {@link SynchronousQueue} are used.
+   */
+  public ExecutorServiceProvider(int corePoolSize, int maxPoolSize, int queueCapacity) {
+    this(
+        corePoolSize,
+        maxPoolSize,
+        queueCapacity,
+        (r, executor1) -> LOG.warn("Executor rejected to handle the payload {}", r));
+  }
+
   @Override
   public ExecutorService get() {
     return executor;