/* * Copyright © 1997 - 1999 IBM Corporation. * * Redistribution and use in source (source code) and binary (object code) * forms, with or without modification, are permitted provided that the * following conditions are met: * 1. Redistributed source code must retain the above copyright notice, this * list of conditions and the disclaimer below. * 2. Redistributed object code must reproduce the above copyright notice, * this list of conditions and the disclaimer below in the documentation * and/or other materials provided with the distribution. * 3. The name of IBM may not be used to endorse or promote products derived * from this software or in any other form without specific prior written * permission from IBM. * 4. Redistribution of any modified code must be labeled "Code derived from * the original OpenCard Framework". * * THIS SOFTWARE IS PROVIDED BY IBM "AS IS" FREE OF CHARGE. IBM SHALL NOT BE * LIABLE FOR INFRINGEMENTS OF THIRD PARTIES RIGHTS BASED ON THIS SOFTWARE. ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IBM DOES NOT WARRANT THAT THE FUNCTIONS CONTAINED IN THIS * SOFTWARE WILL MEET THE USER'S REQUIREMENTS OR THAT THE OPERATION OF IT WILL * BE UNINTERRUPTED OR ERROR-FREE. IN NO EVENT, UNLESS REQUIRED BY APPLICABLE * LAW, SHALL IBM BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ALSO, IBM IS UNDER NO OBLIGATION * TO MAINTAIN, CORRECT, UPDATE, CHANGE, MODIFY, OR OTHERWISE SUPPORT THIS * SOFTWARE. */ /* * Author: Stephan Breideneich (sbreiden@de.ibm.com) * Version: $Id: fieldIO.cpp,v 1.1 1998/04/07 11:14:19 breid Exp $ */ #include #include "fieldIO.h" /******************************************************************************* * getIntField * * This function is used to get the contents of an integer field specified by * an object and a field name. An exception is thrown when something goes wrong. * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * pFieldValue - pointer to integer to contain field value * * Returns: * 0 - everything OK * != 0 - problem occurred, exception was thrown * ******************************************************************************/ long getIntField(JNIEnv *env, jobject obj, char *fieldName, long *pFieldValue) { long rc = 1; jfieldID fid; // first get field ID, then value of field. The java functions will generate any // necessary exceptions. fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "I"); if (fid != NULL) { *pFieldValue = env->GetIntField(obj, fid); if (env->ExceptionOccurred() == NULL) rc = 0; } return rc; } /******************************************************************************* * setIntField * * This function is used to set the contents of an integer field specified by * an object and a field name. An exception is thrown when something goes wrong. * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * fieldValue - integer value to be set * * Returns: * 0 - everything OK * != 0 - problem occurred, exception was thrown * ******************************************************************************/ long setIntField(JNIEnv *env, jobject obj, char *fieldName, long fieldValue) { long rc = 1; jfieldID fid; // first get field ID, then set value of field. The java functions will generate // any necessary exceptions. fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "I"); if (fid != NULL) { env->SetIntField(obj, fid, fieldValue); if (env->ExceptionOccurred() == NULL) rc = 0; } return rc; } /******************************************************************************* * accessByteArray * * This function provides C access to a byte array field of the specified name * contained in an object. * * Arrays accessed through this function must be released through the * releaseByteArray function. * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * field - (output) pointer to pointer to byte array * size - (output) size of the byte array. * * Returns: * 0 - no error * != 0 - problem occurred, exception was thrown * ******************************************************************************/ long accessByteArray(JNIEnv *env, jobject obj, char *fieldName, unsigned char **field, int *pSize) { unsigned char *pByte=NULL; jfieldID fid; jbyteArray jba; long error=1; // first get field ID, then value of field. The java functions will generate any // necessary exceptions. fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "[B"); if (fid != NULL) { jba = (jbyteArray)env->GetObjectField(obj, fid); if (env->ExceptionOccurred() == NULL) { if (jba == NULL) { *pSize = 0; error = 0; } else { *pSize = (int)env->GetArrayLength(jba); pByte = (unsigned char*)env->GetByteArrayElements(jba, 0); if (env->ExceptionOccurred() == NULL) error=0; } /* endif*/ } /* endif*/ } /* endif*/ *field = pByte; return error; } /******************************************************************************* * releaseByteArray * * This function releases access to the java byte array buffer pointed to * by the input pointer. The byte array whose buffer is being released is * a byte array field of an object specifed by obj and fieldName. * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * pByte - buffer to be released * * Returns: * 0 - OK * !=0 - problem occurred, exception was thrown * ******************************************************************************/ long releaseByteArray(JNIEnv *env, jobject obj, char *fieldName, unsigned char *pByte) { long rc=1; jfieldID fid; jbyteArray jba; // first get field ID, then value of field. The java functions will generate any // necessary exceptions. if (pByte == NULL) rc=0; else { fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "[B"); if (fid != NULL) { jba = (jbyteArray)env->GetObjectField(obj, fid); if (env->ExceptionOccurred() == NULL) { env->ReleaseByteArrayElements(jba, (jbyte*)pByte, 0); if (env->ExceptionOccurred() == NULL) rc =0; } /* endif*/ } /* endif*/ } /* endif*/ return rc; } /******************************************************************************* * accessStringField * * This function is used to get the contents of a string field specified by * an object and a field name. An exception is thrown when something goes wrong. * * The field must be released using releaseStringField!! * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * * Returns: * != Null - everything OK, pointer to characters * NULL - problem occurred, exception was thrown * ******************************************************************************/ const char *accessStringField(JNIEnv *env, jobject obj, char *fieldName) { jfieldID fid; jstring jstr; const char *pstr = NULL; // first get field ID, then value of field. The java functions will generate any // necessary exceptions. fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "Ljava/lang/String;"); if (fid != NULL) { jstr = (jstring)env->GetObjectField(obj, fid); if (env->ExceptionOccurred() == NULL) { pstr = env->GetStringUTFChars(jstr, 0); } /* endif*/ } /* endif*/ return pstr; } /******************************************************************************* * releaseStringField * * This function releases access to a java string. * * Parameters: * env - pointer to java environment * obj - designates object containing desired field * fieldName - ASCIIZ string containing name of field * field - Java string field to be released * * Returns: * 0 - everything OK, pointer to characters * != 0 - problem occurred, exception was thrown * ******************************************************************************/ long releaseStringField(JNIEnv *env, jobject obj, char *fieldName, const char *field) { jfieldID fid; jstring jstr; int error = 1; // first get field ID, then value of field. The java functions will generate any // necessary exceptions. fid = env->GetFieldID(env->GetObjectClass(obj), fieldName, "Ljava/lang/String;"); if (fid != NULL) { jstr = (jstring)env->GetObjectField(obj, fid); if (env->ExceptionOccurred() == NULL) { env->ReleaseStringUTFChars(jstr, field); if (env->ExceptionOccurred() == NULL) error = 0; } /* endif*/ } /* endif*/ return error; } // $Log: fieldIO.cpp,v $ // Revision 1.1 1998/04/07 11:14:19 breid // initial version. //