Create a Java FunctionalInterface defining a contract, logic and strategy for running (executing) an Operating System (OS) Process.

Resolves gh-17.

spring-data-geode-test/src/main/java/org/springframework/data/gemfire/tests/process/ProcessRunner.java

@@ -0,0 +1,73 @@
+/*
+ *  Copyright 2019 the original author or authors.
+ *
+ *  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
+ *
+ *       https://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.springframework.data.gemfire.tests.process;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+
+import org.springframework.data.gemfire.tests.util.FileSystemUtils;
+
+/**
+ * The {@link ProcessRunner} interface is a {@link FunctionalInterface} encapsulating the contract, logic and strategy
+ * for running (executing) an Operating System (OS) [JVM] {@link Process}.
+ *
+ * @author John Blum
+ * @see java.io.File
+ * @see java.lang.Process
+ * @see org.springframework.data.gemfire.tests.process.ProcessExecutor
+ * @see org.springframework.data.gemfire.tests.process.ProcessWrapper
+ * @since 1.0.0
+ */
+@FunctionalInterface
+@SuppressWarnings("unused")
+public interface ProcessRunner {
+
+	/**
+	 * Gets the {@link File working directory} in which the {@link Process} will run.
+	 *
+	 * Default to the user directory as defined by {@code System.getProperty("user.dir")}.
+	 *
+	 * @return {@link File} representing the {@literal working directory} in which the {@link Process} will run.
+	 * @see java.io.File
+	 */
+	default File getWorkingDirectory() {
+		return FileSystemUtils.WORKING_DIRECTORY;
+	}
+
+	/**
+	 * Runs a [JVM] {@link Process} defined by the this {@literal run} method.
+	 *
+	 * @param arguments array of {@link String} arguments passed to the program at runtime.
+	 * @return the {@link ProcessWrapper} representing the [JVM] {@link Process}.
+	 * @throws IOException if the {@link Process} could not be run.
+	 * @see org.springframework.data.gemfire.tests.process.ProcessWrapper
+	 */
+	ProcessWrapper run(String... arguments) throws IOException;
+
+	/**
+	 * Runs a [JVM] {@link Process} defined by the this {@literal run} method.
+	 *
+	 * @param arguments {@link List} of {@link String} arguments passed to the program at runtime.
+	 * @return the {@link ProcessWrapper} representing the [JVM] {@link Process}.
+	 * @throws IOException if the {@link Process} could not be run.
+	 * @see org.springframework.data.gemfire.tests.process.ProcessWrapper
+	 * @see #run(String...)
+	 */
+	default ProcessWrapper run(List<String> arguments) throws IOException {
+		return run(arguments.toArray(new String[0]));
+	}
+}