/*

* Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:

*

*/

#ifndef JUTILS_H

#define JUTILS_H

#include <e32base.h>

#include <jni.h>

#include <badesca.h>

#include "javaosheaders.h"

//----------------------------------------------------------------------------

// RJString takes a Java JNI string and converts it to an

// Epoc string. It retains the JNI environment and the string

// in order to release the string resources during destruction

class RJString : public TPtrC16

{

public:

    OS_IMPORT RJString(JNIEnv& aJni, jstring aString);

    OS_IMPORT ~RJString();

private:

    // Prevent accidental copying because of the shared underlying Java

    // string

    RJString(const RJString&);

    RJString& operator=(const RJString&);

private:

    JNIEnv& iJni;

    jstring iString;

};

//----------------------------------------------------------------------------

OS_IMPORT jstring CreateJavaString(JNIEnv& aJni, const TDesC16& aString);

OS_IMPORT void AddToJavaStringArrayL(JNIEnv& aJni, jobjectArray& aContainer, TInt aPosition, const TDesC& aString);

OS_IMPORT jobjectArray CopyToNewJavaStringArrayL(JNIEnv& aJni, const CDesCArray& aNativeArray);

class RJArray

{

public:

    OS_IMPORT RJArray(JNIEnv& aJni);

    OS_IMPORT ~RJArray();

    OS_IMPORT void* GetPrimitiveArrayCriticalLC(jarray aJavaArray, TBool aMutable = EFalse);

    static void CleanupArrayAccess(TAny* aRJArray);

private:

    void ReleasePrimitiveArrayCritical();

private:

    JNIEnv& iJni;

    jarray iJavaArray;

    TUint8* iArrayPtr;

    TBool iMutable;

};

class ArrayUtils

{

public:

    OS_IMPORT static TInt CopyToNative(JNIEnv& aJni, jbyteArray aJavaBuffer,

                                       TInt aOffset, TInt aLength, TDes8& aNativeBuffer);

    OS_IMPORT static TInt CopyToJava(JNIEnv& aJni, const TDesC8& aNativeBuffer,

                                     jbyteArray aJavaBuffer, TInt aOffset, TInt aLength);

    OS_IMPORT static jobjectArray CopyToNewJavaStringArray(JNIEnv& aJni,

            const RPointerArray<HBufC>& aNativeArray);

};

//----------------------------------------------------------------------------

// Constants that define the date/time '00:00, 1 Jan 1970' when used to create a TTime object

const TUint JavaUpperTimeFor1970 = 14474675;

const TUint JavaLowerTimeFor1970 = 254771200;

//----------------------------------------------------------------------------

// Used for converting between a Java jlong value and an Epoc

// TTime and vice-versa. The jlong represents the number of

// milliseconds since 00:00 1st Jan 1970.

class JavaEpocTime

{

public:

    OS_IMPORT static TTime CreateEpocTTime(jlong aJavaTime);

    OS_IMPORT static jlong CreateJavaTime(TTime aEpocTime);

};

//-----------------------------------------------------------------------------

// Creating integer 'handles' from C++ objects for referencing them inside Java

// The shift garauntees a positive integer, so object creation native methods

// can overload the return value to be a handle or an error code

//

// Unhanding the integer requires the destination type to be known, so is

// implemented as a template function, it should be invoked as

//

//      CXyz* xyz=JavaUnhand(aHandle);

//

const TInt KJavaHandleShift=2;

inline TInt JavaMakeHandle(const TAny* aObject)

{

    return reinterpret_cast<TUint>(aObject)>>KJavaHandleShift;

}

template <typename T>

inline T* JavaUnhand(TInt aHandle)

{

    return reinterpret_cast<T*>(aHandle<<KJavaHandleShift);

}

//-----------------------------------------------------------------------------

// Provide the handle/unhand pattern for CBase derived classes, to gain the

// Handle(), Unhand(), New() and TConstructor members, you should derive from

// this class using the following pattern:

//

//  class CXyz : public CJavaPeer<CXyz>

//      {...};

//

// The TConstructor member allows for more complex factory functions,

// providing automatic use of the cleanup stack. Supposing the derived

// class has a second phase constructor ConstructL(), the factory function

// could be:

//

//  TInt CXyz::New(...)

//      {

//      TRAPD(h,TConstructor c;c->ConstructL(...);h=c.GetHandle();)

//      return h;

//      }

//

template <class T>

class CJavaPeer : public CBase

{

protected:

    class TConstructor

    {

    public:

        inline TConstructor(T* aObject)

                :iObject(aObject)

        {

            CleanupStack::PushL(aObject);

        }

        inline TConstructor()

                :iObject(new(ELeave) T)

        {

            CleanupStack::PushL(iObject);

        }

        inline T* operator->() const

        {

            return static_cast<T*>(iObject);

        }

        inline TInt GetHandle()

        {

            CleanupStack::Pop();

            return JavaMakeHandle(iObject);

        }

    private:

        CBase* iObject;

    };

public:

    inline TInt Handle() const

    {

        return JavaMakeHandle(this);

    }

    inline static T& Unhand(TInt aHandle)

    {

        return *JavaUnhand<T>(aHandle);

    }

    static TInt New()

    {

        T* self=new T;

        return self ? self->Handle() : KErrNoMemory;

    }

};

#endif // JUTILS_H