Add RetryOnFailure

DEVSIX-1945

Author: Veronika Lisovskaya

pdftest/src/main/java/com/itextpdf/test/runners/RetryOnFailure.java

@@ -0,0 +1,13 @@
+package com.itextpdf.test.runners;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * In current implementation it has no specified retries count
+ */
+@Retention(RetentionPolicy.CLASS)
+@Target({ ElementType.METHOD})
+public @interface RetryOnFailure {}

pdftest/src/main/java/com/itextpdf/test/runners/RetryRunner.java

@@ -0,0 +1,97 @@
+package com.itextpdf.test.runners;
+
+import org.junit.AssumptionViolatedException;
+import org.junit.Ignore;
+import org.junit.internal.runners.model.EachTestNotifier;
+import org.junit.runner.Description;
+import org.junit.runner.notification.RunNotifier;
+import org.junit.runner.notification.StoppedByUserException;
+import org.junit.runners.BlockJUnit4ClassRunner;
+import org.junit.runners.model.FrameworkMethod;
+import org.junit.runners.model.InitializationError;
+import org.junit.runners.model.Statement;
+
+/**
+ * This class is used for flaky test retry after failure.
+ * In current implementation we use specified retryCount = 3
+ */
+public class RetryRunner extends BlockJUnit4ClassRunner {
+    private final int retryCount = 3;
+    private int failedAttempts = 0;
+
+    public RetryRunner(Class<?> klass) throws InitializationError {
+        super(klass);
+    }
+
+    /**
+     *
+     * @param notifier RunNotifier
+     */
+    public void run(RunNotifier notifier) {
+        EachTestNotifier eachTestNotifier = new EachTestNotifier(notifier, getDescription());
+        Statement statement = classBlock(notifier);
+        try {
+            statement.evaluate();
+        } catch (AssumptionViolatedException ave) {
+            eachTestNotifier.fireTestIgnored();
+        } catch (StoppedByUserException sue) {
+            throw sue;
+        } catch (Throwable throwable) {
+            retry(eachTestNotifier, statement, throwable);
+        }
+    }
+
+    /**
+     *
+     * @param method FrameworkMethod
+     * @param notifier RunNotifier
+     */
+    @Override
+    protected void runChild(final FrameworkMethod method, RunNotifier notifier) {
+        Description description = describeChild(method);
+        if (method.getAnnotation(Ignore.class) != null) {
+            notifier.fireTestIgnored(description);
+        } else {
+            runTestUnit(methodBlock(method), description, notifier);
+        }
+    }
+
+    /**
+     * Runs an atomic test
+     */
+    protected final void runTestUnit(Statement statement, Description description,
+                                     RunNotifier notifier) {
+        failedAttempts = 0;
+        EachTestNotifier eachNotifier = new EachTestNotifier(notifier, description);
+        eachNotifier.fireTestStarted();
+        try {
+            statement.evaluate();
+        } catch (AssumptionViolatedException avee) {
+            eachNotifier.addFailedAssumption(avee);
+        } catch (Throwable e) {
+            retry(eachNotifier, statement, e);
+        } finally {
+            eachNotifier.fireTestFinished();
+        }
+    }
+
+    /**
+     * Retry method, counts failed attempts, adds logging messages
+     * @param notifier EachTestNotifier
+     * @param statement Statement
+     * @param currentThrowable Throwable
+     */
+    private void retry(EachTestNotifier notifier, Statement statement, Throwable currentThrowable) {
+        Throwable caughtThrowable = currentThrowable;
+        while (retryCount > failedAttempts) {
+            try {
+                statement.evaluate();
+            } catch (Throwable e) {
+                System.out.println("Test Failed on attempt #" + (failedAttempts + 1));
+                failedAttempts++;
+                caughtThrowable = e;
+            }
+        }
+        notifier.addFailure(caughtThrowable);
+    }
+}