1 /*

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

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

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

     6 * which accompanies this distribution, and is available

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

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Base class for all native implementation of stream types

    15 *

    16 */

    17 

    18 

    19 #ifndef NATIVESTREAMBASE_H

    20 #define NATIVESTREAMBASE_H

    21 

    22 #include <jni.h>

    23 

    24 namespace java

    25 {

    26 

    27 /**

    28 * This is the base class for Native Peer of streams.

    29 * StreamConnectionBase in will make calls to the native side to get/send data.

    30 * It will have stored a handle to the Object and uses it to call these methods.

    31 *

    32 * Usage:

    33 * Please ensure that this class comes first in the line of inheritance as shown.

    34 *

    35 * @code

    36 * class StreamConnectionX : public NativeStreamBase, public AllOtherClasses

    37 * @endcode

    38 *

    39 */

    40 class NativeStreamBase

    41 {

    42 public:

    43     /**

    44     * ReadBytes is called once the buffer at the InputStream in Java runs

    45     * out of data.

    46     * How this function should be called.

    47     * @param[in]  aJavaBuffer: A byte array of length 512 bytes

    48     * @return return should be the number of bytes read. If error, then the

    49     *         value of errno should be negated and returned. (return -errno)

    50     */

    51     virtual int readBytes(JNIEnv& aJni, jbyteArray aJavaBuffer) = 0;

    52 

    53     /**

    54     * WriteBytes is called once buffer at the OutputStream in Java overflows.

    55     * It is also called if flush() is called at the Java side.

    56     * How this function should be called.

    57     * @param[in]  aJavaBuffer: A byte array of length aLength

    58     * @return return should be the number of bytes written. If error, then the

    59     *         value of errno should be negated and returned. (return -errno)

    60     */

    61     virtual int writeBytes(JNIEnv& aJni, jbyteArray aJavaBuffer,

    62                            int aOffset, int aLength) = 0;

    63 

    64     /**

    65     * StopReading is called once InputStream is closed from the Application.

    66     */

    67     virtual void stopReading() = 0;

    68 

    69     /**

    70     * StopWriting is called once OutputStream is closed from the Application.

    71     */

    72     virtual void stopWriting() = 0;

    73 

    74     /**

    75     * Defines the size of the buffer to be held on the native side. Should be

    76     * same as the buffer in the InputStream

    77     */

    78     int mBufferSize;

    79 

    80     /**

    81      * SetBufferSize is called during StreamConnectionBase construction.

    82      * This is to keep both Java and Native Buffers in sync.

    83      */

    84     void setBufferSize(int aSize)

    85     {

    86         mBufferSize = aSize;

    87     }

    88 

    89     virtual int available()

    90     {

    91         return 0;

    92     }

    93 };

    94 

    95 }  //end namespace java

    96 

    97 

    98 #endif // NATIVESTREAMBASE_H