Add base class for creating modular JAR files.

Author: plamentotev

src/main/java/org/codehaus/plexus/archiver/jar/ModularJarArchiver.java

@@ -0,0 +1,76 @@
+/**
+ *
+ * Copyright 2018 The Apache Software Foundation
+ *
+ * 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.codehaus.plexus.archiver.jar;
+
+/**
+ * Base class for creating modular JAR archives.
+ *
+ * Subclasses are required to be able to handle both
+ * JAR archives with module descriptor (modular JAR)
+ * and without ("regular" JAR).
+ * That would allow clients of this class to use
+ * it without prior knowledge if the classes
+ * they are going to add are part of module
+ * (contain module descriptor class) or not.
+ *
+ * @since 3.6
+ */
+public abstract class ModularJarArchiver
+    extends JarArchiver
+{
+    private String moduleMainClass;
+
+    private String moduleVersion;
+
+    public String getModuleMainClass()
+    {
+        return moduleMainClass;
+    }
+
+    /**
+     * Sets the module main class.
+     * Ignored if the JAR file does not contain
+     * module descriptor.
+     *
+     * <p>Note that implementations may choose
+     * to replace the value set in the manifest as well.
+     *
+     * @param moduleMainClass the module main class.
+     */
+    public void setModuleMainClass( String moduleMainClass )
+    {
+        this.moduleMainClass = moduleMainClass;
+    }
+
+    public String getModuleVersion()
+    {
+        return moduleVersion;
+    }
+
+    /**
+     * Sets the module version.
+     * Ignored if the JAR file does not contain
+     * module descriptor.
+     *
+     * @param moduleVersion the module version.
+     */
+    public void setModuleVersion( String moduleVersion )
+    {
+        this.moduleVersion = moduleVersion;
+    }
+
+}