path: root/src/java/com/jogamp/gluegen/JavaMethodBindingEmitter.java

/*
 * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistribution of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed or intended for use
 * in the design, construction, operation or maintenance of any nuclear
 * facility.
 *
 * Sun gratefully acknowledges that this software was originally authored
 * and developed by Kenneth Bradley Russell and Christopher John Kline.
 */

package com.jogamp.gluegen;

import com.jogamp.gluegen.cgram.HeaderParser;
import com.jogamp.gluegen.cgram.types.ArrayType;
import com.jogamp.gluegen.cgram.types.CompoundType;
import com.jogamp.gluegen.cgram.types.EnumType;
import com.jogamp.gluegen.cgram.types.PointerType;
import com.jogamp.gluegen.cgram.types.Type;

import java.io.PrintWriter;
import java.text.MessageFormat;
import java.util.List;

/**
 * An emitter that emits only the interface for a Java<->C JNI binding.
 */
public class JavaMethodBindingEmitter extends FunctionEmitter {

  public static final EmissionModifier PUBLIC = new EmissionModifier("public");
  public static final EmissionModifier PROTECTED = new EmissionModifier("protected");
  public static final EmissionModifier PRIVATE = new EmissionModifier("private");
  public static final EmissionModifier ABSTRACT = new EmissionModifier("abstract");
  public static final EmissionModifier FINAL = new EmissionModifier("final");
  public static final EmissionModifier NATIVE = new EmissionModifier("native");
  public static final EmissionModifier SYNCHRONIZED = new EmissionModifier("synchronized");

  protected final CommentEmitter defaultJavaCommentEmitter = new DefaultCommentEmitter();
  protected final CommentEmitter defaultInterfaceCommentEmitter = new InterfaceCommentEmitter();

  // Exception type raised in the generated code if runtime checks fail
  private String runtimeExceptionType;
  private String unsupportedExceptionType;

  protected boolean emitBody;
  protected boolean eraseBufferAndArrayTypes;
  protected boolean useNIOOnly;
  protected boolean useNIODirectOnly;
  protected boolean forImplementingMethodCall;
  protected boolean forDirectBufferImplementation;
  protected boolean forIndirectBufferAndArrayImplementation;
  protected boolean isUnimplemented;
  protected boolean tagNativeBinding;

  protected MethodBinding binding;

  // Manually-specified prologue and epilogue code
  protected List<String> prologue;
  protected List<String> epilogue;

  // A non-null value indicates that rather than returning a compound
  // type accessor we are returning an array of such accessors; this
  // expression is a MessageFormat string taking the names of the
  // incoming Java arguments as parameters and computing as an int the
  // number of elements of the returned array.
  private String returnedArrayLengthExpression;

  // A suffix used to create a temporary outgoing array of Buffers to
  // represent an array of compound type wrappers
  private static final String COMPOUND_ARRAY_SUFFIX = "_buf_array_copy";

  // Only present to provide more clear comments
  private JavaConfiguration cfg;

  public JavaMethodBindingEmitter(MethodBinding binding,
                                  PrintWriter output,
                                  String runtimeExceptionType,
                                  String unsupportedExceptionType,
                                  boolean emitBody,
                                  boolean tagNativeBinding,
                                  boolean eraseBufferAndArrayTypes,
                                  boolean useNIOOnly,
                                  boolean useNIODirectOnly,
                                  boolean forImplementingMethodCall,
                                  boolean forDirectBufferImplementation,
                                  boolean forIndirectBufferAndArrayImplementation,
                                  boolean isUnimplemented,
                                  boolean isInterface,
                                  JavaConfiguration configuration) {
    super(output, isInterface);
    this.binding = binding;
    this.runtimeExceptionType = runtimeExceptionType;
    this.unsupportedExceptionType = unsupportedExceptionType;
    this.emitBody = emitBody;
    this.tagNativeBinding = tagNativeBinding;
    this.eraseBufferAndArrayTypes = eraseBufferAndArrayTypes;
    this.useNIOOnly = useNIOOnly;
    this.useNIODirectOnly = useNIODirectOnly;
    this.forImplementingMethodCall = forImplementingMethodCall;
    this.forDirectBufferImplementation = forDirectBufferImplementation;
    this.forIndirectBufferAndArrayImplementation = forIndirectBufferAndArrayImplementation;
    this.isUnimplemented = isUnimplemented;
    if (forImplementingMethodCall) {
      setCommentEmitter(defaultJavaCommentEmitter);
    } else {
      setCommentEmitter(defaultInterfaceCommentEmitter);
    }
    cfg = configuration;
  }

  public JavaMethodBindingEmitter(JavaMethodBindingEmitter arg) {
    super(arg);
    binding                       = arg.binding;
    runtimeExceptionType          = arg.runtimeExceptionType;
    unsupportedExceptionType      = arg.unsupportedExceptionType;
    emitBody                      = arg.emitBody;
    tagNativeBinding              = arg.tagNativeBinding;
    eraseBufferAndArrayTypes      = arg.eraseBufferAndArrayTypes;
    useNIOOnly                    = arg.useNIOOnly;
    useNIODirectOnly              = arg.useNIODirectOnly;
    forImplementingMethodCall     = arg.forImplementingMethodCall;
    forDirectBufferImplementation = arg.forDirectBufferImplementation;
    forIndirectBufferAndArrayImplementation = arg.forIndirectBufferAndArrayImplementation;
    isUnimplemented               = arg.isUnimplemented;
    prologue                      = arg.prologue;
    epilogue                      = arg.epilogue;
    returnedArrayLengthExpression = arg.returnedArrayLengthExpression;
    cfg                           = arg.cfg;
  }

  public final MethodBinding getBinding() { return binding; }

  public boolean isForImplementingMethodCall() { return forImplementingMethodCall; }
  public boolean isForDirectBufferImplementation() { return forDirectBufferImplementation; }
  public boolean isForIndirectBufferAndArrayImplementation() { return forIndirectBufferAndArrayImplementation; }

  @Override
  public String getName() {
    return binding.getName();
  }

  protected String getArgumentName(int i) {
    return binding.getArgumentName(i);
  }

  /** The type of exception (must subclass
      <code>java.lang.RuntimeException</code>) raised if runtime
      checks fail in the generated code. */
  public String getRuntimeExceptionType() {
    return runtimeExceptionType;
  }

  public String getUnsupportedExceptionType() {
    return unsupportedExceptionType;
  }

  /** If the underlying function returns an array (currently only
      arrays of compound types are supported) as opposed to a pointer
      to an object, this method should be called to provide a
      MessageFormat string containing an expression that computes the
      number of elements of the returned array. The parameters to the
      MessageFormat expression are the names of the incoming Java
      arguments. */
  public void setReturnedArrayLengthExpression(String expr) {
    returnedArrayLengthExpression = expr;
  }

  /** Sets the manually-generated prologue code for this emitter. */
  public void setPrologue(List<String> prologue) {
    this.prologue = prologue;
  }

  /** Sets the manually-generated epilogue code for this emitter. */
  public void setEpilogue(List<String> epilogue) {
    this.epilogue = epilogue;
  }

  /** Indicates whether this emitter will print only a signature, or
      whether it will emit Java code for the body of the method as
      well. */
  public boolean signatureOnly() {
    return !emitBody;
  }

  /** Accessor for subclasses. */
  public void setEmitBody(boolean emitBody) {
    this.emitBody = emitBody;
  }

  /** Accessor for subclasses. */
  public void setEraseBufferAndArrayTypes(boolean erase) {
    this.eraseBufferAndArrayTypes = erase;
  }

  /** Accessor for subclasses. */
  public void setForImplementingMethodCall(boolean impl) {
    this.forImplementingMethodCall = impl;
  }

  /** Accessor for subclasses. */
  public void setForDirectBufferImplementation(boolean direct) {
    this.forDirectBufferImplementation = direct;
  }

  /** Accessor for subclasses. */
  public void setForIndirectBufferAndArrayImplementation(boolean indirect) {
    this.forIndirectBufferAndArrayImplementation = indirect;
  }

  @Override
  protected void emitReturnType(PrintWriter writer)  {
    writer.print(getReturnTypeString(false));
  }

  protected String erasedTypeString(JavaType type, boolean skipBuffers) {
    if (eraseBufferAndArrayTypes) {
      if (type.isNIOBuffer()) {
        if (!skipBuffers) {
          // Direct buffers and arrays sent down as Object (but
          // returned as e.g. ByteBuffer)
          return "Object";
        }
        if (!type.isNIOByteBuffer()) {
          // Return buffer requiring change of view from ByteBuffer to e.g. LongBuffer
          return "ByteBuffer";
        }
      } else if (type.isPrimitiveArray()) {
        if (!skipBuffers) {
          // Direct buffers and arrays sent down as Object (but
          // returned as e.g. ByteBuffer)
          return "Object";
        }
      } else if (type.isNIOBufferArray()) {
        // Arrays of direct Buffers sent down as Object[]
        // (Note we don't yet support returning void**)
        return "Object[]";
      } else if (type.isCompoundTypeWrapper()) {
        // Compound type wrappers are unwrapped to ByteBuffer
        return "ByteBuffer";
      } else if (type.isArrayOfCompoundTypeWrappers()) {
        if (skipBuffers) {
          return "ByteBuffer";
        } else {
          // In the case where this is called with a false skipBuffers
          // argument we want to erase the array of compound type
          // wrappers to ByteBuffer[]
          return "ByteBuffer[]";
        }
      }
    }
    String name = type.getName();
    int index = name.lastIndexOf('.')+1; // always >= 0
    name = name.substring(index);

    if (type.isArrayOfCompoundTypeWrappers()) {
      // We don't want to bake the array specification into the type name
      return name + "[]";
    }
    return name;
  }

  protected String getReturnTypeString(boolean skipArray) {
    // The first arm of the "if" clause is used by the glue code
    // generation for arrays of compound type wrappers
    if (skipArray ||
    // The following arm is used by most other kinds of return types
        (getReturnedArrayLengthExpression() == null &&
         !binding.getJavaReturnType().isArrayOfCompoundTypeWrappers()) ||
    // The following arm is used specifically to get the splitting up
    // of one returned ByteBuffer into an array of compound type
    // wrappers to work (e.g., XGetVisualInfo)
        (eraseBufferAndArrayTypes &&
         binding.getJavaReturnType().isCompoundTypeWrapper() &&
         (getReturnedArrayLengthExpression() != null))) {
      return erasedTypeString(binding.getJavaReturnType(), true);
    }
    return erasedTypeString(binding.getJavaReturnType(), true) + "[]";
  }

  @Override
  protected void emitName(PrintWriter writer)  {
    if (forImplementingMethodCall) {
      writer.print(getImplMethodName());
    } else {
      writer.print(getName());
    }
  }

  @Override
  protected int emitArguments(PrintWriter writer) {
    boolean needComma = false;
    int numEmitted = 0;

    if (forImplementingMethodCall  && binding.hasContainingType()) {
      // Always emit outgoing "this" argument
      writer.print("ByteBuffer ");
      writer.print(javaThisArgumentName());
      ++numEmitted;
      needComma = true;
    }

    for (int i = 0; i < binding.getNumArguments(); i++) {
      JavaType type = binding.getJavaArgumentType(i);
      if (type.isVoid()) {
        // Make sure this is the only param to the method; if it isn't,
        // there's something wrong with our parsing of the headers.
        if (binding.getNumArguments() != 1) {
          throw new InternalError(
            "\"void\" argument type found in " +
            "multi-argument function \"" + binding + "\"");
        }
        continue;
      }

      if (type.isJNIEnv() || binding.isArgumentThisPointer(i)) {
        // Don't need to expose these at the Java level
        continue;
      }

      if (needComma) {
        writer.print(", ");
      }

      writer.print(erasedTypeString(type, false));
      writer.print(" ");
      writer.print(getArgumentName(i));

      ++numEmitted;
      needComma = true;

      // Add Buffer and array index offset arguments after each associated argument
      if (forDirectBufferImplementation || forIndirectBufferAndArrayImplementation) {
        if (type.isNIOBuffer()) {
          writer.print(", int " + byteOffsetArgName(i));
          if(!useNIODirectOnly) {
              writer.print(", boolean " + isNIOArgName(i));
          }
        } else if (type.isNIOBufferArray()) {
          writer.print(", int[] " +  byteOffsetArrayArgName(i));
        }
      }

      // Add offset argument after each primitive array
      if (type.isPrimitiveArray()) {
        if(useNIOOnly) {
            throw new RuntimeException("NIO[Direct]Only "+binding+" is set, but "+getArgumentName(i)+" is a primitive array");
        }
        writer.print(", int " + offsetArgName(i));
      }
    }
    return numEmitted;
  }


  protected String getImplMethodName() {
    return binding.getName() + ( useNIODirectOnly ? "0" : "1" );
  }

  protected String byteOffsetArgName(int i) {
    return byteOffsetArgName(getArgumentName(i));
  }

  protected String byteOffsetArgName(String s) {
    return s + "_byte_offset";
  }

  protected String isNIOArgName(int i) {
    return isNIOArgName(binding.getArgumentName(i));
  }

  protected String isNIOArgName(String s) {
    return s + "_is_direct";
  }

  protected String byteOffsetArrayArgName(int i) {
    return getArgumentName(i) + "_byte_offset_array";
  }

  protected String offsetArgName(int i) {
    return getArgumentName(i) + "_offset";
  }

  @Override
  protected void emitBody(PrintWriter writer)  {
    if (!emitBody) {
      writer.println(';');
    } else {
      MethodBinding mBinding = getBinding();
      writer.println("  {");
      writer.println();
      if (isUnimplemented) {
        writer.println("    throw new " + getUnsupportedExceptionType() + "(\"Unimplemented\");");
      } else {
        emitPrologueOrEpilogue(prologue, writer);
        emitPreCallSetup(mBinding, writer);
        //emitReturnVariableSetup(binding, writer);
        emitReturnVariableSetupAndCall(mBinding, writer);
      }
      writer.println("  }");
    }
  }

  protected void emitPrologueOrEpilogue(List<String> code, PrintWriter writer) {
    if (code != null) {
      String[] argumentNames = argumentNameArray();
      for (String str : code) {
        try {
            MessageFormat fmt = new MessageFormat(str);
            writer.println("    " + fmt.format(argumentNames));
        } catch (IllegalArgumentException e) {
            // (Poorly) handle case where prologue / epilogue contains blocks of code with braces
            writer.println("    " + str);
        }
      }
    }
  }

  protected void emitPreCallSetup(MethodBinding binding, PrintWriter writer) {
    emitArrayLengthAndNIOBufferChecks(binding, writer);
    emitCompoundArrayCopies(binding, writer);
  }

  protected void emitArrayLengthAndNIOBufferChecks(MethodBinding binding, PrintWriter writer) {

    // Check lengths of any incoming arrays if necessary
    for (int i = 0; i < binding.getNumArguments(); i++) {
      Type type = binding.getCArgumentType(i);
      if (type.isArray()) {
        ArrayType arrayType = type.asArray();
        writer.println("    if (" + getArgumentName(i) + ".length < " +
                       arrayType.getLength() + ")");
        writer.println("      throw new " + getRuntimeExceptionType() +
                       "(\"Length of array \\\"" + getArgumentName(i) +
                       "\\\" was less than the required " + arrayType.getLength() + "\");");
        // FIXME: What is this ??? Until resolved - throw an exception !
        throw new RuntimeException("????? "+binding+": binding.getCArgumentType("+i+").isArray(): "+type);
      } else {
        JavaType javaType = binding.getJavaArgumentType(i);
        if (javaType.isNIOBuffer()) {
          if (useNIODirectOnly) {
            writer.println("    if (!Buffers.isDirect(" + getArgumentName(i) + "))");
            writer.println("      throw new " + getRuntimeExceptionType() + "(\"Argument \\\"" +
                           getArgumentName(i) + "\\\" is not a direct buffer\");");
          } else {
            writer.println("    final boolean " + isNIOArgName(i) + " = Buffers.isDirect(" + getArgumentName(i) + ");");
          }
        } else if (javaType.isNIOBufferArray()) {
          // All buffers passed down in an array of NIO buffers must be direct
          String argName = getArgumentName(i);
          String arrayName = byteOffsetArrayArgName(i);
          writer.println("    final int[] " + arrayName + " = new int[" + argName + ".length];");
          // Check direct buffer properties of all buffers within
          writer.println("    if (" + argName + " != null) {");
          writer.println("      for (int _ctr = 0; _ctr < " + argName + ".length; _ctr++) {");
          writer.println("        if (!Buffers.isDirect(" + argName + "[_ctr])) {");
          writer.println("          throw new " + getRuntimeExceptionType() +
                         "(\"Element \" + _ctr + \" of argument \\\"" +
                         getArgumentName(i) + "\\\" was not a direct buffer\");");
          writer.println("        }");
          // get the Buffer Array offset values and save them into another array to send down to JNI
          writer.print  ("        " + arrayName + "[_ctr] = Buffers.getDirectBufferByteOffset(");
          writer.println(argName + "[_ctr]);");
          writer.println("      }");
          writer.println("    }");
        } else if (javaType.isPrimitiveArray()) {
          String argName = getArgumentName(i);
          String offsetArg = offsetArgName(i);
          writer.println("    if(" + argName + " != null && " + argName + ".length <= " + offsetArg + ")");
          writer.print  ("      throw new " + getRuntimeExceptionType());
          writer.println("(\"array offset argument \\\"" + offsetArg + "\\\" (\" + " + offsetArg +
                         " + \") equals or exceeds array length (\" + " + argName + ".length + \")\");");
        }
      }
    }
  }

  protected void emitCompoundArrayCopies(MethodBinding binding, PrintWriter writer) {
    // If the method binding uses outgoing arrays of compound type
    // wrappers, we need to generate a temporary copy of this array
    // into a ByteBuffer[] for processing by the native code
    if (binding.signatureUsesArraysOfCompoundTypeWrappers()) {
      for (int i = 0; i < binding.getNumArguments(); i++) {
        JavaType javaType = binding.getJavaArgumentType(i);
        if (javaType.isArrayOfCompoundTypeWrappers()) {
          String argName = getArgumentName(i);
          String tempArrayName = argName + COMPOUND_ARRAY_SUFFIX;
          writer.println("    final ByteBuffer[] " + tempArrayName + " = new ByteBuffer[" + argName + ".length];");
          writer.println("    for (int _ctr = 0; _ctr < + " + argName + ".length; _ctr++) {");
          writer.println("      " + javaType.getName() + " _tmp = " + argName + "[_ctr];");
          writer.println("      " + tempArrayName + "[_ctr] = ((_tmp == null) ? null : _tmp.getBuffer());");
          writer.println("    }");
        }
      }
    }
  }

  protected void emitCall(MethodBinding binding, PrintWriter writer) {
    writer.print(getImplMethodName());
    writer.print("(");
    emitCallArguments(binding, writer);
    writer.print(");");
  }


  protected void emitReturnVariableSetupAndCall(MethodBinding binding, PrintWriter writer) {
    writer.print("    ");
    JavaType returnType = binding.getJavaReturnType();
    boolean needsResultAssignment = false;

    if (!returnType.isVoid()) {
      if (returnType.isCompoundTypeWrapper() ||
          returnType.isNIOBuffer()) {
        writer.println("final ByteBuffer _res;");
        needsResultAssignment = true;
      } else if (returnType.isArrayOfCompoundTypeWrappers()) {
        writer.println("final ByteBuffer[] _res;");
        needsResultAssignment = true;
      } else if (((epilogue != null) && (epilogue.size() > 0)) ||
                 binding.signatureUsesArraysOfCompoundTypeWrappers()) {
        writer.print("final ");
        emitReturnType(writer);
        writer.println(" _res;");
        needsResultAssignment = true;
      }
    }

    if (needsResultAssignment) {
      writer.print("    _res = ");
    } else {
      writer.print("    ");
      if (!returnType.isVoid()) {
        writer.print("return ");
      }
    }

    emitCall(binding, writer);
    writer.println();

    emitPostCallCleanup(binding, writer);
    emitPrologueOrEpilogue(epilogue, writer);
    if (needsResultAssignment) {
      emitCallResultReturn(binding, writer);
    }
  }

  protected int emitCallArguments(MethodBinding binding, PrintWriter writer) {
    boolean needComma = false;
    int numArgsEmitted = 0;

    if (binding.hasContainingType()) {
      // Emit this pointer
      assert(binding.getContainingType().isCompoundTypeWrapper());
      writer.print("getBuffer()");
      needComma = true;
      ++numArgsEmitted;
    }
    for (int i = 0; i < binding.getNumArguments(); i++) {
      JavaType type = binding.getJavaArgumentType(i);
      if (type.isJNIEnv() || binding.isArgumentThisPointer(i)) {
        // Don't need to expose these at the Java level
        continue;
      }

      if (type.isVoid()) {
        // Make sure this is the only param to the method; if it isn't,
        // there's something wrong with our parsing of the headers.
        assert(binding.getNumArguments() == 1);
        continue;
      }

      if (needComma) {
        writer.print(", ");
      }

      if (type.isCompoundTypeWrapper()) {
        writer.print("((");
      }

      if (type.isNIOBuffer()) {
          if(type.isNIOPointerBuffer()) {
              if (useNIODirectOnly) {
                  writer.print( getArgumentName(i)+ " != null ? " + getArgumentName(i) + ".getBuffer() : null");
              } else {
                  writer.print( isNIOArgName(i) + " ? ( " + getArgumentName(i)+ " != null ? " + getArgumentName(i) + ".getBuffer() : null )");
                  writer.print( " : Buffers.getArray(" + getArgumentName(i) + ")" );
              }
          } else {
              if (useNIODirectOnly) {
                  writer.print( getArgumentName(i) );
              } else {
                  writer.print( isNIOArgName(i) + " ? " + getArgumentName(i) + " : Buffers.getArray(" + getArgumentName(i) + ")" );
              }
          }
      } else if (type.isArrayOfCompoundTypeWrappers()) {
          writer.print(getArgumentName(i) + COMPOUND_ARRAY_SUFFIX);
      } else {
          writer.print(getArgumentName(i));
      }

      if (type.isCompoundTypeWrapper()) {
        writer.print(" == null) ? null : ");
        writer.print(getArgumentName(i));
        writer.print(".getBuffer())");
      }

      if (type.isNIOBuffer()) {
        if (useNIODirectOnly) {
          writer.print( ", Buffers.getDirectBufferByteOffset(" + getArgumentName(i) + ")");
        } else {
          writer.print( ", " + isNIOArgName(i) + " ? Buffers.getDirectBufferByteOffset(" + getArgumentName(i) + ")");
          writer.print(        " : Buffers.getIndirectBufferByteOffset(" + getArgumentName(i) + ")");
        }
      } else if (type.isNIOBufferArray()) {
        writer.print(", " + byteOffsetArrayArgName(i));
      } else if (type.isPrimitiveArray()) {
        if(type.isFloatArray()) {
          writer.print(", Buffers.SIZEOF_FLOAT * ");
        } else if(type.isDoubleArray()) {
          writer.print(", Buffers.SIZEOF_DOUBLE * ");
        } else if(type.isByteArray()) {
          writer.print(", ");
        } else if(type.isLongArray()) {
          writer.print(", Buffers.SIZEOF_LONG * ");
        } else if(type.isShortArray()) {
          writer.print(", Buffers.SIZEOF_SHORT * ");
        } else if(type.isIntArray()) {
          writer.print(", Buffers.SIZEOF_INT * ");
        } else {
          throw new RuntimeException("Unsupported type for calculating array offset argument for " +
                                     getArgumentName(i) +
                                     " -- error occurred while processing Java glue code for " + getName());
        }
        writer.print(offsetArgName(i));
      }

      if (type.isNIOBuffer()) {
        if (!useNIODirectOnly) {
            writer.print( ", " + isNIOArgName(i) );
        }
      } else if (type.isPrimitiveArray()) {
        if (useNIOOnly) {
            throw new RuntimeException("NIO[Direct]Only "+binding+" is set, but "+getArgumentName(i)+" is a primitive array");
        }
        writer.print( ", false");
      }

      needComma = true;
      ++numArgsEmitted;
    }
    return numArgsEmitted;
  }

  protected void emitPostCallCleanup(MethodBinding binding, PrintWriter writer) {
    if (binding.signatureUsesArraysOfCompoundTypeWrappers()) {
      // For each such array, we need to take the ByteBuffer[] that
      // came back from the C method invocation and wrap the
      // ByteBuffers back into the wrapper types
      for (int i = 0; i < binding.getNumArguments(); i++) {
        JavaType javaArgType = binding.getJavaArgumentType(i);
        if (javaArgType.isArrayOfCompoundTypeWrappers()) {
          String argName = binding.getArgumentName(i);
          writer.println("    for (int _ctr = 0; _ctr < " + argName + ".length; _ctr++) {");
          writer.println("      if ((" + argName + "[_ctr] == null && " + argName + COMPOUND_ARRAY_SUFFIX + "[_ctr] == null) ||");
          writer.println("          (" + argName + "[_ctr] != null && " + argName + "[_ctr].getBuffer() == " + argName + COMPOUND_ARRAY_SUFFIX + "[_ctr])) {");
          writer.println("        // No copy back needed");
          writer.println("      } else {");
          writer.println("        if (" + argName + COMPOUND_ARRAY_SUFFIX + "[_ctr] == null) {");
          writer.println("          " + argName + "[_ctr] = null;");
          writer.println("        } else {");
          writer.println("          " + argName + "[_ctr] = " + javaArgType.getName() + ".create(" + argName + COMPOUND_ARRAY_SUFFIX + "[_ctr]);");
          writer.println("        }");
          writer.println("      }");
          writer.println("    }");
        }
      }
    }
  }

  protected void emitCallResultReturn(MethodBinding binding, PrintWriter writer) {
    JavaType returnType = binding.getJavaReturnType();

    if (returnType.isCompoundTypeWrapper()) {
      String fmt = getReturnedArrayLengthExpression();
      writer.println("    if (_res == null) return null;");
      if (fmt == null) {
        writer.print("    return " + returnType.getName() + ".create(Buffers.nativeOrder(_res))");
      } else {
        writer.println("    Buffers.nativeOrder(_res);");
        String expr = new MessageFormat(fmt).format(argumentNameArray());
        PointerType cReturnTypePointer = binding.getCReturnType().asPointer();
        CompoundType cReturnType = null;
        if (cReturnTypePointer != null) {
          cReturnType = cReturnTypePointer.getTargetType().asCompound();
        }
        if (cReturnType == null) {
          throw new RuntimeException("ReturnedArrayLength directive currently only supported for pointers to compound types " +
                                     "(error occurred while generating Java glue code for " + getName() + ")");
        }
        writer.println("    final " + getReturnTypeString(false) + " _retarray = new " + getReturnTypeString(true) + "[" + expr + "];");
        writer.println("    for (int _count = 0; _count < " + expr + "; _count++) {");
        // Create temporary ByteBuffer slice
        // FIXME: probably need Type.getAlignedSize() for arrays of
        // compound types (rounding up to machine-dependent alignment)
        writer.println("      _res.position(_count * " + getReturnTypeString(true) + ".size());");
        writer.println("      _res.limit   ((1 + _count) * " + getReturnTypeString(true) + ".size());");
        writer.println("      final ByteBuffer _tmp = _res.slice();");
        writer.println("      Buffers.nativeOrder(_tmp);");
        writer.println("      _res.position(0);");
        writer.println("      _res.limit(_res.capacity());");
        writer.println("      _retarray[_count] = " + getReturnTypeString(true) + ".create(_tmp);");
        writer.println("    }");
        writer.print  ("    return _retarray");
      }
      writer.println(";");
    } else if (returnType.isNIOBuffer()) {
      writer.println("    if (_res == null) return null;");
      writer.println("    Buffers.nativeOrder(_res);");
      if (!returnType.isNIOByteBuffer()) {
        // See whether we have to expand pointers to longs
        if (getBinding().getCReturnType().pointerDepth() >= 2) {
          if (returnType.isNIOPointerBuffer()) {
              writer.println("    return PointerBuffer.wrap(_res);");
          } else if (returnType.isNIOLongBuffer()) {
              writer.println("    return _res.asLongBuffer();");
          } else {
            throw new RuntimeException("While emitting glue code for " + getName() +
                                       ": can not legally make pointers opaque to anything but PointerBuffer or LongBuffer/long");
          }
        } else if (getBinding().getCReturnType().pointerDepth() == 1 && returnType.isNIOLongBuffer()) {
          writer.println("    return _res.asLongBuffer();");
        } else {
          String returnTypeName = returnType.getName().substring("java.nio.".length());
          writer.println("    return _res.as" + returnTypeName + "();");
        }
      } else {
        writer.println("    return _res;");
      }
    } else if (returnType.isArrayOfCompoundTypeWrappers()) {
      writer.println("    if (_res == null) return null;");
      writer.println("    final " + getReturnTypeString(false) + " _retarray = new " + getReturnTypeString(true) + "[_res.length];");
      writer.println("    for (int _count = 0; _count < _res.length; _count++) {");
      writer.println("      _retarray[_count] = " + getReturnTypeString(true) + ".create(_res[_count]);");
      writer.println("    }");
      writer.println("    return _retarray;");
    } else {
      // Assume it's a primitive type or other type we don't have to
      // do any conversion on
      writer.println("    return _res;");
    }
  }

  protected String[] argumentNameArray() {
    String[] argumentNames = new String[binding.getNumArguments()];
    for (int i = 0; i < binding.getNumArguments(); i++) {
      argumentNames[i] = getArgumentName(i);
      if (binding.getJavaArgumentType(i).isPrimitiveArray()) {
        // Add on _offset argument in comma-separated expression
        argumentNames[i] = argumentNames[i] + ", " + offsetArgName(i);
      }
    }
    return argumentNames;
  }

  public static String javaThisArgumentName() {
    return "jthis0";
  }

  @Override
  protected String getCommentStartString() { return "/** "; }

  @Override
  protected String getBaseIndentString() { return "  "; }

  protected String getReturnedArrayLengthExpression() {
    return returnedArrayLengthExpression;
  }

  /**
   * Class that emits a generic comment for JavaMethodBindingEmitters; the comment
   * includes the C signature of the native method that is being bound by the
   * emitter java method.
   */
  protected class DefaultCommentEmitter implements CommentEmitter {
    @Override
    public void emit(FunctionEmitter emitter, PrintWriter writer) {
      emitBeginning(emitter, writer);
      emitBindingCSignature(((JavaMethodBindingEmitter)emitter).getBinding(), writer);
      emitEnding(emitter, writer);
    }
    protected void emitBeginning(FunctionEmitter emitter, PrintWriter writer) {
      writer.print("Entry point to C language function: ");
    }
    protected void emitBindingCSignature(MethodBinding binding, PrintWriter writer) {
      writer.print("<code> ");
      writer.print(binding.getCSymbol().toString(tagNativeBinding));
      writer.print(" </code> ");
    }
    protected void emitEnding(FunctionEmitter emitter, PrintWriter writer) {
      // If argument type is a named enum, then emit a comment detailing the
      // acceptable values of that enum.
      // If we're emitting a direct buffer variant only, then declare
      // that the NIO buffer arguments must be direct.
      MethodBinding binding = ((JavaMethodBindingEmitter)emitter).getBinding();
      for (int i = 0; i < binding.getNumArguments(); i++) {
        Type type = binding.getCArgumentType(i);
        JavaType javaType = binding.getJavaArgumentType(i);
        // don't emit param comments for anonymous enums, since we can't
        // distinguish between the values found within multiple anonymous
        // enums in the same C translation unit.
        if (type.isEnum() && !HeaderParser.ANONYMOUS_ENUM_NAME.equals(type.getName())) {
          EnumType enumType = (EnumType)type;
          writer.println();
          writer.print(emitter.getBaseIndentString());
          writer.print("    ");
          writer.print("@param ");
          writer.print(getArgumentName(i));
          writer.print(" valid values are: <code>");
          for (int j = 0; j < enumType.getNumEnumerates(); ++j) {
            if (j>0) writer.print(", ");
            writer.print(enumType.getEnumName(j));
          }
          writer.println("</code>");
        } else if (javaType.isNIOBuffer()) {
          writer.println();
          writer.print(emitter.getBaseIndentString());
          writer.print("    ");
          writer.print("@param ");
          writer.print(getArgumentName(i));
          if (useNIODirectOnly) {
              writer.print(" a direct only {@link " + javaType.getName() + "}");
          } else {
              writer.print(" a direct or array-backed {@link " + javaType.getName() + "}");
          }
        }
      }
    }
  }

    protected class InterfaceCommentEmitter extends JavaMethodBindingEmitter.DefaultCommentEmitter {

        @Override
        protected void emitBeginning(FunctionEmitter emitter,
                PrintWriter writer) {
            writer.print("Interface to C language function: <br> ");
        }
    }
}