#152 - Fix IoProperties.javaHome setter.

We now correctly set the javaHome variable instead of the workDir if the io.javaHome property is set.
Include the property in the template file and add the maven.parallelize=true flag as well.

Closes: #152

src/test/java/org/springframework/data/release/io/IoPropertiesUnitTests.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2020 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.release.io;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+/**
+ * @author Christoph Strobl
+ */
+public class IoPropertiesUnitTests {
+
+	@TempDir File tempDir;
+	IoProperties properties;
+
+	@BeforeEach
+	void beforeEach() {
+		properties = new IoProperties();
+	}
+
+	@Test // GH-152
+	void setJavaHomeToDir() {
+
+		properties.setJavaHome(tempDir.getPath());
+
+		assertThat(properties.getJavaHome()).isNotNull().isDirectory();
+	}
+
+	@Test // GH-152
+	void setJavaHomeIgnoresEmptyString() {
+
+		properties.setJavaHome("");
+
+		assertThat(properties.getJavaHome()).isNull();
+	}
+
+	@Test // GH-152
+	void setJavaHomeIgnoresFile() throws IOException {
+
+		File f = new File(tempDir, "java.txt");
+		f.createNewFile();
+
+		properties.setJavaHome(f.getPath());
+
+		assertThat(properties.getJavaHome()).isNull();
+	}
+
+	@Test // GH-152
+	void setJavaHomeIgnoresDirectoryThatDoesNotExist() throws IOException {
+
+		properties.setJavaHome(new File(tempDir, "java-bin").getPath());
+
+		assertThat(properties.getJavaHome()).isNull();
+	}
+}