org.jcae.opencascade/src/jnistream.cxx

   1 #include "jnistream.hxx"
   2
   3 //#define DEBUG
   4 using namespace std;
   5
   6 static void jthrow(JNIEnv *env, const char *name, const char *msg)
   7 {
   8         jclass cls = env->FindClass(name);
   9         /* if cls is NULL, an exception has already been thrown => remove it because it's from the JVM*/
  10         if (cls == NULL)
  11         {
  12                 env->ExceptionClear();
  13                 jthrow(env,name,msg);
  14         }
  15         else
  16         {
  17                 if(env->ThrowNew(cls, msg)<0)
  18                 {
  19                         //the throw exception failled
  20                         std::cout<<"#JNI throw exception failled !"<<std::endl;
  21                         std::cout<<name<<"\t : "<<msg<<std::endl;
  22                 }
  23                 /* free the local ref */
  24                 env->DeleteLocalRef(cls);
  25         }
  26 }
  27
  28 jnistreambuf::~jnistreambuf()
  29 {
  30         delete[] nativeBuffer;
  31 }
  32
  33 jnistreambuf::jnistreambuf(JNIEnv * env, jobject jstream, int bufferSize):
  34         env(env), jstream(jstream)
  35 {
  36 #ifdef DEBUG
  37         cerr << "jnistreambuf::jnistreambuf [start]" << endl;
  38 #endif
  39         nativeBuffer = new char[bufferSize];
  40         fullNioBuffer=env->NewDirectByteBuffer(nativeBuffer, bufferSize);
  41
  42         jclass inputStreamClass = env->FindClass("java/nio/channels/ReadableByteChannel");
  43         jclass outputStreamClass = env->FindClass("java/nio/channels/WritableByteChannel");
  44
  45         readMID = env->GetMethodID(inputStreamClass, "read","(Ljava/nio/ByteBuffer;)I");
  46         writeMID = env->GetMethodID(outputStreamClass, "write","(Ljava/nio/ByteBuffer;)I");
  47
  48         bool in=env->IsInstanceOf(jstream, inputStreamClass)!=0;
  49         bool out=env->IsInstanceOf(jstream, outputStreamClass)!=0;
  50
  51         if(in)
  52         {
  53 #ifdef DEBUG
  54         cerr << "jnistreambuf::jnistreambuf: init reading buffer" << endl;
  55 #endif
  56                 setg(nativeBuffer,     // beginning of putback area
  57                          nativeBuffer,     // read position
  58                          nativeBuffer);    // end position
  59         }
  60
  61         if(out)
  62         {
  63 #ifdef DEBUG
  64         cerr << "jnistreambuf::jnistreambuf: init writting buffer [start]" << endl;
  65 #endif
  66                 setp( nativeBuffer, nativeBuffer + bufferSize );
  67
  68 #ifdef DEBUG
  69         cerr << "jnistreambuf::jnistreambuf: init writting buffer [done]" << endl;
  70 #endif
  71         }
  72
  73         if(!out && !in)
  74         {
  75                 jthrow(env, "java/lang/ClassCastException", "InputStream or OutputStream expected");
  76         }
  77
  78 #ifdef DEBUG
  79         cerr << "jnistreambuf::jnistreambuf [done]" << endl;
  80 #endif
  81 }
  82
  83 int jnistreambuf::underflow()
  84 {
  85 #ifdef DEBUG
  86         cerr << "jnistreambuf::underflow" << endl;
  87 #endif
  88         // used for input buffer only
  89     if ( gptr() && ( gptr() < egptr()))
  90         return * reinterpret_cast<unsigned char *>( gptr());
  91
  92         //read the java bytes
  93     int num = env->CallIntMethod(jstream, readMID, fullNioBuffer);
  94
  95     if (num <= 0) // ERROR or EOF
  96         return EOF;
  97
  98     // reset buffer pointers
  99     setg( eback(),   // beginning of putback area
 100           eback(),                 // read position
 101           eback() + num);          // end of buffer
 102
 103     // return next character
 104     return * reinterpret_cast<unsigned char *>( gptr());
 105 }
 106
 107 int jnistreambuf::overflow( int c)
 108 {
 109 #ifdef DEBUG
 110         cerr << "jnistreambuf::overflow" << endl;
 111 #endif
 112         // used for output buffer only
 113     if (c != EOF) {
 114         *pptr() = c;
 115         pbump(1);
 116     }
 117
 118     if ( flush_buffer() == EOF)
 119         return EOF;
 120     return c;
 121 }
 122
 123 int jnistreambuf::sync()
 124 {
 125 #ifdef DEBUG
 126         cerr << "jnistreambuf::sync()" << endl;
 127 #endif
 128     // Changed to use flush_buffer() instead of overflow( EOF)
 129     // which caused improper behavior with std::endl and flush(),
 130     // bug reported by Vincent Ricard.
 131     if ( pptr() && pptr() > pbase()) {
 132         if ( flush_buffer() == EOF)
 133             return -1;
 134     }
 135     return 0;
 136 }
 137
 138 int jnistreambuf::flush_buffer()
 139 {
 140 #ifdef DEBUG
 141         cerr << "jnistreambuf::flush_buffer" << endl;
 142         //for(char * p=pbase(); p!=pptr(); p++) cerr << *p;
 143 #endif
 144     // Separate the writing of the buffer from overflow() and
 145     // sync() operation.
 146     int w = pptr() - pbase();
 147
 148         //write the c chars
 149         jobject nioBuffer;
 150
 151         if(pptr()==epptr())
 152                 nioBuffer=fullNioBuffer;
 153         else
 154                 nioBuffer=env->NewDirectByteBuffer(pbase(), w);
 155
 156     env->CallIntMethod(jstream, writeMID, nioBuffer);
 157
 158     pbump( -w);
 159     return w;
 160 }
 161