InterimittentRule generic junit rule

Change-Id: I375ed04cb6c44f6c923d048523c008b28883700d

dsf-gdb/org.eclipse.cdt.tests.dsf.gdb/src/org/eclipse/cdt/tests/dsf/gdb/framework/InterimittentRule.java

@@ -0,0 +1,72 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Alena Laskavaia and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Alena Laskavaia - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.tests.dsf.gdb.framework;
+
+import org.junit.rules.MethodRule;
+import org.junit.runners.model.FrameworkMethod;
+import org.junit.runners.model.Statement;
+
+/**
+ * This is the rule to add to tests that rarely fail randomly and you want to keep them but cannot figure out they fail.
+ * It is safe to use it in any class, it will only apply to tests which have @InterimittentRule annotation
+ * <code>
+
+ public @Rule InterimittentRule rule = new InterimittentRule();
+
+ @Test
+ @InterimittentRule(repetition = 3)
+ public void someTest (){}
+
+ * </code>
+ */
+public class InterimittentRule implements MethodRule {
+	public static class RunIntermittent extends Statement {
+		private final FrameworkMethod method;
+		private final Statement statement;
+
+		public RunIntermittent(FrameworkMethod method, Statement statement) {
+			this.method = method;
+			this.statement = statement;
+		}
+
+		@Override
+		public void evaluate() throws Throwable {
+			int repetition = 1;
+			Intermittent methodAnnot = method.getAnnotation(Intermittent.class);
+			if (methodAnnot != null) {
+				repetition = methodAnnot.repetition();
+			} else {
+				Intermittent classAnnot = method.getDeclaringClass().getAnnotation(Intermittent.class);
+				if (classAnnot != null) {
+					repetition = classAnnot.repetition();
+				}
+			}
+			if (repetition > 1) {
+				for (int i = 0; i < repetition; i++) {
+					try {
+						statement.evaluate();
+						break; // did not fail yay, we are done
+					} catch (Throwable e) {
+						if (i < repetition - 1)
+							continue; // try again
+						throw e;
+					}
+				}
+			} else
+				statement.evaluate();
+		}
+	}
+
+	@Override
+	public Statement apply(Statement base, final FrameworkMethod method, final Object target) {
+		return new RunIntermittent(method, base);
+	}
+}

dsf-gdb/org.eclipse.cdt.tests.dsf.gdb/src/org/eclipse/cdt/tests/dsf/gdb/framework/Intermittent.java

@@ -0,0 +1,23 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Alena Laskavaia and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Alena Laskavaia - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.tests.dsf.gdb.framework;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+@Target({ METHOD, TYPE })
+@Retention(RUNTIME)
+public @interface Intermittent {
+	int repetition() default 5;
+}