Bug 923: Remove dependency of CStruct annotation processor _generation_ and generated_class_user due to Java8 issues.

Java8's annotation processor as embedded within javac does not allow
referencing not-yet existing generated classes in a class source code
which will produce these generated classes via the annotation process.

Example:

+++
import com.jogamp.gluegen.structgen.CStruct;

public class Lala {
  @CStruct(name="RenderingConfig", header="TestStruct01.h")
  public RenderingConfig config;
}
+++

Above example illustrates that the type 'RenderingConfig'
does not exist at time of processing the annotation.
The type will be created via the annotation process itself.

Even though we pass '-proc:only', i.e. skip java compilation,
Java8's annotation processing via javac fails in such case.

We see this as a bug within javac's annotation processing itself!

+++

This workaround splits the annotation process and using the class as
generated by the former.

To allow this to work, CStruct receives a new field 'jname'
allowing to enforce the java-name of the structure
using a dummy field type like boolean.

  @CStruct(name="RenderingConfig", jname="RenderingConfig", header="TestStruct01.h")
  public boolean dummy;

Further more CStruct can be annotated on the package, i.e. 'package-info.java',
avoiding the dependency problem altogether.
To support multiple header files and types,
'CStructs' has been introduced using an array of 'CStruct'.

  @CStructs({@CStruct(name="RenderingConfig", header="TestStruct01.h"), @CStruct(name="Pixel", header="TestStruct02.h")})
  package com.jogamp.gluegen.test.junit.structgen;

Tests:
  - Build w/ Java7 and Java8
  - Validated 'major version 50' (Java 6) class files (OK)

1 files changed, 118 insertions, 115 deletions

diff --git a/src/java/com/jogamp/gluegen/JavaEmitter.java b/src/java/com/jogamp/gluegen/JavaEmitter.java
index ec8757c..3f4fa9e 100644
--- a/src/java/com/jogamp/gluegen/JavaEmitter.java
+++ b/src/java/com/jogamp/gluegen/JavaEmitter.java
@@ -836,69 +836,74 @@ public class JavaEmitter implements GlueEmitter {
       }
     }
 
-    String structClassPkg = cfg.packageForStruct(name);
-    PrintWriter writer = null;
-    PrintWriter newWriter = null;
+    final String structClassPkg = cfg.packageForStruct(name);
+    final PrintWriter javaWriter;
+    final PrintWriter jniWriter;
     try  {
-      writer = openFile(
-        cfg.javaOutputDir() + File.separator +
-        CodeGenUtils.packageAsPath(structClassPkg) +
-        File.separator + containingTypeName + ".java", containingTypeName);
-      CodeGenUtils.emitAutogeneratedWarning(writer, this);
-      if (needsNativeCode) {
-        String nRoot = cfg.nativeOutputDir();
-        if (cfg.nativeOutputUsesJavaHierarchy()) {
-          nRoot += File.separator + CodeGenUtils.packageAsPath(cfg.packageName());
+        javaWriter = openFile(cfg.javaOutputDir() + File.separator +
+                              CodeGenUtils.packageAsPath(structClassPkg) +
+                              File.separator + containingTypeName + ".java", containingTypeName);
+        if( null == javaWriter ) {
+            // suppress output if openFile deliberately returns null.
+            return;
+        }
+        CodeGenUtils.emitAutogeneratedWarning(javaWriter, this);
+        if (needsNativeCode) {
+            String nRoot = cfg.nativeOutputDir();
+            if (cfg.nativeOutputUsesJavaHierarchy()) {
+                nRoot += File.separator + CodeGenUtils.packageAsPath(cfg.packageName());
+            }
+            jniWriter = openFile(nRoot + File.separator + containingTypeName + "_JNI.c", containingTypeName);
+            CodeGenUtils.emitAutogeneratedWarning(jniWriter, this);
+            emitCHeader(jniWriter, containingTypeName);
+        } else {
+            jniWriter = null;
         }
-        newWriter = openFile(nRoot + File.separator + containingTypeName + "_JNI.c", containingTypeName);
-        CodeGenUtils.emitAutogeneratedWarning(newWriter, this);
-        emitCHeader(newWriter, containingTypeName);
-      }
     } catch(Exception e)   {
-      throw new RuntimeException("Unable to open files for emission of struct class", e);
+        throw new RuntimeException("Unable to open files for emission of struct class", e);
     }
 
-    writer.println();
-    writer.println("package " + structClassPkg + ";");
-    writer.println();
-    writer.println("import java.nio.*;");
-    writer.println();
+    javaWriter.println();
+    javaWriter.println("package " + structClassPkg + ";");
+    javaWriter.println();
+    javaWriter.println("import java.nio.*;");
+    javaWriter.println();
 
-    writer.println("import " + cfg.gluegenRuntimePackage() + ".*;");
-    writer.println("import " + DynamicLookupHelper.class.getPackage().getName() + ".*;");
-    writer.println("import " + Buffers.class.getPackage().getName() + ".*;");
-    writer.println("import " + MachineDescriptionRuntime.class.getName() + ";");
-    writer.println();
+    javaWriter.println("import " + cfg.gluegenRuntimePackage() + ".*;");
+    javaWriter.println("import " + DynamicLookupHelper.class.getPackage().getName() + ".*;");
+    javaWriter.println("import " + Buffers.class.getPackage().getName() + ".*;");
+    javaWriter.println("import " + MachineDescriptionRuntime.class.getName() + ";");
+    javaWriter.println();
     List<String> imports = cfg.imports();
     for (String str : imports) {
-      writer.print("import ");
-      writer.print(str);
-      writer.println(";");
+      javaWriter.print("import ");
+      javaWriter.print(str);
+      javaWriter.println(";");
     }
-    writer.println();
+    javaWriter.println();
     List<String> javadoc = cfg.javadocForClass(containingTypeName);
     for (String doc : javadoc) {
-      writer.println(doc);
+      javaWriter.println(doc);
     }
-    writer.print("public class " + containingTypeName + " ");
+    javaWriter.print("public class " + containingTypeName + " ");
     boolean firstIteration = true;
     List<String> userSpecifiedInterfaces = cfg.implementedInterfaces(containingTypeName);
     for (String userInterface : userSpecifiedInterfaces) {
       if (firstIteration) {
-        writer.print("implements ");
+        javaWriter.print("implements ");
       }
       firstIteration = false;
-      writer.print(userInterface);
-      writer.print(" ");
-    }
-    writer.println("{");
-    writer.println();
-    writer.println("  StructAccessor accessor;");
-    writer.println();
-    writer.println("  private static final int mdIdx = MachineDescriptionRuntime.getStatic().ordinal();");
-    writer.println();
+      javaWriter.print(userInterface);
+      javaWriter.print(" ");
+    }
+    javaWriter.println("{");
+    javaWriter.println();
+    javaWriter.println("  StructAccessor accessor;");
+    javaWriter.println();
+    javaWriter.println("  private static final int mdIdx = MachineDescriptionRuntime.getStatic().ordinal();");
+    javaWriter.println();
     // generate all offset and size arrays
-    generateOffsetAndSizeArrays(writer, containingTypeName, structType, null); /* w/o offset */
+    generateOffsetAndSizeArrays(javaWriter, containingTypeName, structType, null); /* w/o offset */
     for (int i = 0; i < structType.getNumFields(); i++) {
       final Field field = structType.getField(i);
       final Type fieldType = field.getType();
@@ -917,14 +922,14 @@ public class JavaEmitter implements GlueEmitter {
                                        field + "\" in type \"" + name + "\")");
           }
 
-          generateOffsetAndSizeArrays(writer, fieldName, fieldType, field);
+          generateOffsetAndSizeArrays(javaWriter, fieldName, fieldType, field);
         } else if (fieldType.isArray()) {
             Type baseElementType = field.getType().asArray().getBaseElementType();
 
             if(!baseElementType.isPrimitive())
                 break;
 
-            generateOffsetAndSizeArrays(writer, fieldName, null, field); /* w/o size */
+            generateOffsetAndSizeArrays(javaWriter, fieldName, null, field); /* w/o size */
         } else {
           JavaType externalJavaType = null;
           try {
@@ -936,7 +941,7 @@ public class JavaEmitter implements GlueEmitter {
           }
           if (externalJavaType.isPrimitive()) {
             // Primitive type
-            generateOffsetAndSizeArrays(writer, fieldName, null, field); /* w/o size */
+            generateOffsetAndSizeArrays(javaWriter, fieldName, null, field); /* w/o size */
           } else {
             // FIXME
             LOG.log(WARNING, "Complicated fields (field \"{0}\" of type \"{1}\") not implemented yet", new Object[]{field, name});
@@ -946,27 +951,27 @@ public class JavaEmitter implements GlueEmitter {
         }
       }
     }
-    writer.println();
-
-    writer.println("  public static int size() {");
-    writer.println("    return "+containingTypeName+"_size[mdIdx];");
-    writer.println("  }");
-    writer.println();
-    writer.println("  public static " + containingTypeName + " create() {");
-    writer.println("    return create(Buffers.newDirectByteBuffer(size()));");
-    writer.println("  }");
-    writer.println();
-    writer.println("  public static " + containingTypeName + " create(java.nio.ByteBuffer buf) {");
-    writer.println("      return new " + containingTypeName + "(buf);");
-    writer.println("  }");
-    writer.println();
-    writer.println("  " + containingTypeName + "(java.nio.ByteBuffer buf) {");
-    writer.println("    accessor = new StructAccessor(buf);");
-    writer.println("  }");
-    writer.println();
-    writer.println("  public java.nio.ByteBuffer getBuffer() {");
-    writer.println("    return accessor.getBuffer();");
-    writer.println("  }");
+    javaWriter.println();
+
+    javaWriter.println("  public static int size() {");
+    javaWriter.println("    return "+containingTypeName+"_size[mdIdx];");
+    javaWriter.println("  }");
+    javaWriter.println();
+    javaWriter.println("  public static " + containingTypeName + " create() {");
+    javaWriter.println("    return create(Buffers.newDirectByteBuffer(size()));");
+    javaWriter.println("  }");
+    javaWriter.println();
+    javaWriter.println("  public static " + containingTypeName + " create(java.nio.ByteBuffer buf) {");
+    javaWriter.println("      return new " + containingTypeName + "(buf);");
+    javaWriter.println("  }");
+    javaWriter.println();
+    javaWriter.println("  " + containingTypeName + "(java.nio.ByteBuffer buf) {");
+    javaWriter.println("    accessor = new StructAccessor(buf);");
+    javaWriter.println("  }");
+    javaWriter.println();
+    javaWriter.println("  public java.nio.ByteBuffer getBuffer() {");
+    javaWriter.println("    return accessor.getBuffer();");
+    javaWriter.println("  }");
 
     for (int i = 0; i < structType.getNumFields(); i++) {
       final Field field = structType.getField(i);
@@ -983,12 +988,12 @@ public class JavaEmitter implements GlueEmitter {
               FunctionSymbol funcSym      = new FunctionSymbol(fieldName, funcType);
               MethodBinding  binding      = bindFunction(funcSym, containingType, containingCType, machDescJava);
               binding.findThisPointer(); // FIXME: need to provide option to disable this on per-function basis
-              writer.println();
+              javaWriter.println();
 
               // Emit public Java entry point for calling this function pointer
               JavaMethodBindingEmitter emitter =
                 new JavaMethodBindingEmitter(binding,
-                                             writer,
+                                             javaWriter,
                                              cfg.runtimeExceptionType(),
                                              cfg.unsupportedExceptionType(),
                                              true,
@@ -1008,7 +1013,7 @@ public class JavaEmitter implements GlueEmitter {
               // Emit private native Java entry point for calling this function pointer
               emitter =
                 new JavaMethodBindingEmitter(binding,
-                                             writer,
+                                             javaWriter,
                                              cfg.runtimeExceptionType(),
                                              cfg.unsupportedExceptionType(),
                                              false,
@@ -1029,7 +1034,7 @@ public class JavaEmitter implements GlueEmitter {
               // Emit (private) C entry point for calling this function pointer
               CMethodBindingEmitter cEmitter =
                 new CMethodBindingEmitter(binding,
-                                          newWriter,
+                                          jniWriter,
                                           structClassPkg,
                                           containingTypeName,
                                           true, // FIXME: this is optional at this point
@@ -1052,12 +1057,12 @@ public class JavaEmitter implements GlueEmitter {
                                        field + "\" in type \"" + name + "\")");
           }
 
-          writer.println();
-          generateGetterSignature(writer, false, fieldType.getName(), capitalizeString(fieldName));
-          writer.println(" {");
-          writer.println("    return " + fieldType.getName() + ".create( accessor.slice( " +
+          javaWriter.println();
+          generateGetterSignature(javaWriter, false, fieldType.getName(), capitalizeString(fieldName));
+          javaWriter.println(" {");
+          javaWriter.println("    return " + fieldType.getName() + ".create( accessor.slice( " +
                            fieldName+"_offset[mdIdx], "+fieldName+"_size[mdIdx] ) );");
-          writer.println(" }");
+          javaWriter.println(" }");
 
         } else if (fieldType.isArray()) {
 
@@ -1070,18 +1075,18 @@ public class JavaEmitter implements GlueEmitter {
             String capitalized = capitalizeString(fieldName);
 
             // Setter
-            writer.println();
-            generateSetterSignature(writer, false, containingTypeName, capitalized, paramType+"[]");
-            writer.println(" {");
-            writer.print  ("    accessor.set" + capitalizeString(paramType) + "sAt(" + fieldName+"_offset[mdIdx], val);");
-            writer.println("    return this;");
-            writer.println("  }");
-            writer.println();
+            javaWriter.println();
+            generateSetterSignature(javaWriter, false, containingTypeName, capitalized, paramType+"[]");
+            javaWriter.println(" {");
+            javaWriter.print  ("    accessor.set" + capitalizeString(paramType) + "sAt(" + fieldName+"_offset[mdIdx], val);");
+            javaWriter.println("    return this;");
+            javaWriter.println("  }");
+            javaWriter.println();
             // Getter
-            generateGetterSignature(writer, false, paramType+"[]", capitalized);
-            writer.println(" {");
-            writer.print  ("    return accessor.get" + capitalizeString(paramType) + "sAt(" + fieldName+"_offset[mdIdx], new " +paramType+"["+fieldType.asArray().getLength()+"]);");
-            writer.println(" }");
+            generateGetterSignature(javaWriter, false, paramType+"[]", capitalized);
+            javaWriter.println(" {");
+            javaWriter.print  ("    return accessor.get" + capitalizeString(paramType) + "sAt(" + fieldName+"_offset[mdIdx], new " +paramType+"["+fieldType.asArray().getLength()+"]);");
+            javaWriter.println(" }");
         } else {
           JavaType javaType = null;
 
@@ -1111,40 +1116,40 @@ public class JavaEmitter implements GlueEmitter {
                                    ", sizeDenominator "+sizeDenominator);
             }
 
-            writer.println();
+            javaWriter.println();
             // Setter
-            generateSetterSignature(writer, false, containingTypeName, capFieldName, javaTypeName);
-            writer.println(" {");
+            generateSetterSignature(javaWriter, false, containingTypeName, capFieldName, javaTypeName);
+            javaWriter.println(" {");
             if( fieldTypeNativeSizeFixed ) {
-                writer.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val);");
+                javaWriter.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val);");
             } else {
-                writer.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val, MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
+                javaWriter.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val, MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
             }
-            writer.println("    return this;");
-            writer.println("  }");
-            writer.println();
+            javaWriter.println("    return this;");
+            javaWriter.println("  }");
+            javaWriter.println();
 
             // Getter
-            generateGetterSignature(writer, false, javaTypeName, capFieldName);
-            writer.println(" {");
-            writer.print  ("    return ");
+            generateGetterSignature(javaWriter, false, javaTypeName, capFieldName);
+            javaWriter.println(" {");
+            javaWriter.print  ("    return ");
             if( fieldTypeNativeSizeFixed ) {
-                writer.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx]);");
+                javaWriter.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx]);");
             } else {
-                writer.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
+                javaWriter.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
             }
-            writer.println("  }");
+            javaWriter.println("  }");
           }
         }
       }
     }
-    emitCustomJavaCode(writer, containingTypeName);
-    writer.println("}");
-    writer.flush();
-    writer.close();
+    emitCustomJavaCode(javaWriter, containingTypeName);
+    javaWriter.println("}");
+    javaWriter.flush();
+    javaWriter.close();
     if (needsNativeCode) {
-      newWriter.flush();
-      newWriter.close();
+      jniWriter.flush();
+      jniWriter.close();
     }
   }
   @Override
@@ -1415,17 +1420,15 @@ public class JavaEmitter implements GlueEmitter {
   /**
    * @param filename the class's full filename to open w/ write access
    * @param simpleClassName the simple class name, i.e. w/o package name
-   * @return a {@link PrintWriter} instance to write the class source file
+   * @return a {@link PrintWriter} instance to write the class source file or <code>null</code> to suppress output!
    * @throws IOException
    */
   protected PrintWriter openFile(String filename, String simpleClassName) throws IOException {
     //System.out.println("Trying to open: " + filename);
-    File file = new File(filename);
-    String parentDir = file.getParent();
-    if (parentDir != null)
-    {
-      File pDirFile = new File(parentDir);
-      pDirFile.mkdirs();
+    final File file = new File(filename);
+    final String parentDir = file.getParent();
+    if (parentDir != null) {
+        new File(parentDir).mkdirs();
     }
     return new PrintWriter(new BufferedWriter(new FileWriter(file)));
   }