KEYCLOAK-5716 KEYCLOAK-5738 Avoid infinispan deadlock. Ensure code-to-token works correctly in cross-dc

common/src/main/java/org/keycloak/common/util/Retry.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2017 Red Hat, Inc. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.keycloak.common.util;
+
+/**
+ * @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
+ */
+public class Retry {
+
+    /**
+     * Runs the given {@code runnable} at most {@code retryCount} times until it passes,
+     * leaving {@code intervalMillis} milliseconds between the invocations.
+     * The runnable is reexecuted if it throws a {@link RuntimeException} or {@link AssertionError}.
+     * @param runnable
+     * @param attemptsCount Total number of attempts to execute the {@code runnable}
+     * @param intervalMillis
+     * @return Index of the first successful invocation, starting from 0.
+     */
+    public static int execute(Runnable runnable, int attemptsCount, long intervalMillis) {
+        int executionIndex = 0;
+        while (true) {
+            try {
+                runnable.run();
+                return executionIndex;
+            } catch (RuntimeException | AssertionError e) {
+                attemptsCount--;
+                executionIndex++;
+                if (attemptsCount > 0) {
+                    try {
+                        if (intervalMillis > 0) {
+                            Thread.sleep(intervalMillis);
+                        }
+                    } catch (InterruptedException ie) {
+                        ie.addSuppressed(e);
+                        throw new RuntimeException(ie);
+                    }
+                } else {
+                    throw e;
+                }
+            }
+        }
+    }
+
+    /**
+     * Runs the given {@code runnable} at most {@code retryCount} times until it passes,
+     * leaving {@code intervalMillis} milliseconds between the invocations.
+     * The runnable is reexecuted if it throws a {@link RuntimeException} or {@link AssertionError}.
+     * @param supplier
+     * @param attemptsCount Total number of attempts to execute the {@code runnable}
+     * @param intervalMillis
+     * @return Value generated by the {@code supplier}.
+     */
+    public static <T> T call(Supplier<T> supplier, int attemptsCount, long intervalMillis) {
+        while (true) {
+            try {
+                return supplier.get();
+            } catch (RuntimeException | AssertionError e) {
+                attemptsCount--;
+                if (attemptsCount > 0) {
+                    try {
+                        if (intervalMillis > 0) {
+                            Thread.sleep(intervalMillis);
+                        }
+                    } catch (InterruptedException ie) {
+                        ie.addSuppressed(e);
+                        throw new RuntimeException(ie);
+                    }
+                } else {
+                    throw e;
+                }
+            }
+        }
+    }
+
+
+    /**
+     * Needed here just because java.util.function.Supplier defined from Java 8
+     */
+    public interface Supplier<T> {
+
+        /**
+         * Gets a result.
+         *
+         * @return a result
+         */
+        T get();
+    }
+
+
+}