[MCOMPILER-485] Fixes internal string format in generated package-inf…

…o.class (#95)

* [MCOMPILER-485] Add failing integration test for class file contents

The internal package string in the class file should contain a forward
slash

* [MCOMPILER-485] Always use forward slash for internal package name

Per JLS 4.2.1 if the file separator character is not a forward slash,
replace it

* [MCOMPILER-485] Call ClassWriter#visit before ClassWriter#visitSource

Javadocs for org.objectweb.asm.ClassVisitor specify "The methods of this
class must be called in the following order: visit [ visitSource ] ..."

src/it/MCOMPILER-485/invoker.properties

@@ -0,0 +1,19 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+
+invoker.goals = clean compile
+invoker.buildResult = success

src/it/MCOMPILER-485/pom.xml

@@ -0,0 +1,44 @@
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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.
+-->
+
+<project
+  xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>blah</groupId>
+  <artifactId>blah</artifactId>
+  <version>1.0</version>
+  <packaging>jar</packaging>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>@pom.version@</version>
+      </plugin>
+    </plugins>
+  </build>
+</project>

src/it/MCOMPILER-485/src/main/java/dummy/HelloWorld.java

@@ -0,0 +1,28 @@
+package dummy;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+
+public class HelloWorld
+{
+   public static void main(String[] argv) {
+      System.out.println("Hello World");
+   }
+}

src/it/MCOMPILER-485/src/main/java/dummy/package-info.java

@@ -0,0 +1,23 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+/**
+ * This is the package javadoc
+ */
+package dummy;

src/it/MCOMPILER-485/verify.groovy

@@ -0,0 +1,24 @@
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+def packageInfoClassFile = new File( basedir, 'target/classes/dummy/package-info.class' )
+def packageInfoBytes = packageInfoClassFile.bytes
+def packageInfoHex = packageInfoBytes.encodeHex().toString()
+// "dummy/package-info" hex encoded
+assert packageInfoHex.contains( '64756d6d792f7061636b6167652d696e666f' )

src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java

@@ -1363,12 +1363,16 @@ private void createMissingPackageInfoClasses( CompilerConfiguration compilerConf
     private byte[] generatePackage( CompilerConfiguration compilerConfiguration, String javaFile )
     {
         int version = getOpcode( compilerConfiguration );
+        String internalPackageName = javaFile.substring( 0, javaFile.length() - ".java".length() );
+        if ( File.separatorChar != '/' )
+        {
+            internalPackageName = internalPackageName.replace( File.separatorChar, '/' );
+        }
         ClassWriter cw = new ClassWriter( 0 );
-        cw.visitSource( "package-info.java", null );
         cw.visit( version,
                 Opcodes.ACC_SYNTHETIC | Opcodes.ACC_ABSTRACT | Opcodes.ACC_INTERFACE,
-                javaFile.substring( 0, javaFile.length() - ".java".length() ),
-                null, "java/lang/Object", null );
+                internalPackageName, null, "java/lang/Object", null );
+        cw.visitSource( "package-info.java", null );
         return cw.toByteArray();
     }