src/java.desktop/macosx/native/libosxapp/JNIUtilities.h - platform/libcore - Git at Google

 /*
  * Copyright (c) 2020, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 #ifndef __JNIUTILITIES_H
 #define __JNIUTILITIES_H

 #include "jni.h"
 #include "jni_util.h"

 #import <Cocoa/Cocoa.h>

 /********        LOGGING SUPPORT    *********/

 #define LOG_NULL(dst_var, name) \
    if (dst_var == NULL) { \
        NSLog(@"Bad JNI lookup %s\n", name); \
        NSLog(@"%@",[NSThread callStackSymbols]); \
        if ([NSThread isMainThread] == NO) { \
            if ((*env)->ExceptionOccurred(env) == NULL) { \
               JNU_ThrowInternalError(env, "Bad JNI Lookup"); \
            } \
        } else { \
               if ((*env)->ExceptionOccurred(env) != NULL) { \
                   (*env)->ExceptionDescribe(env); \
            } \
        } \
        [NSException raise:NSGenericException format:@"JNI Lookup Exception"];  \
     }

 /********        GET CLASS SUPPORT    *********/

 #define GET_CLASS(dst_var, cls) \
      if (dst_var == NULL) { \
          dst_var = (*env)->FindClass(env, cls); \
          if (dst_var != NULL) dst_var = (*env)->NewGlobalRef(env, dst_var); \
      } \
      LOG_NULL(dst_var, cls); \
      CHECK_NULL(dst_var);

 #define DECLARE_CLASS(dst_var, cls) \
     static jclass dst_var = NULL; \
     GET_CLASS(dst_var, cls);

 #define GET_CLASS_RETURN(dst_var, cls, ret) \
      if (dst_var == NULL) { \
          dst_var = (*env)->FindClass(env, cls); \
          if (dst_var != NULL) dst_var = (*env)->NewGlobalRef(env, dst_var); \
      } \
      LOG_NULL(dst_var, cls); \
      CHECK_NULL_RETURN(dst_var, ret);

 #define DECLARE_CLASS_RETURN(dst_var, cls, ret) \
     static jclass dst_var = NULL; \
     GET_CLASS_RETURN(dst_var, cls, ret);


 /********        GET METHOD SUPPORT    *********/

 #define GET_METHOD(dst_var, cls, name, signature) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetMethodID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL(dst_var);

 #define DECLARE_METHOD(dst_var, cls, name, signature) \
      static jmethodID dst_var = NULL; \
      GET_METHOD(dst_var, cls, name, signature);

 #define GET_METHOD_RETURN(dst_var, cls, name, signature, ret) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetMethodID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL_RETURN(dst_var, ret);

 #define DECLARE_METHOD_RETURN(dst_var, cls, name, signature, ret) \
      static jmethodID dst_var = NULL; \
      GET_METHOD_RETURN(dst_var, cls, name, signature, ret);

 #define GET_STATIC_METHOD(dst_var, cls, name, signature) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetStaticMethodID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL(dst_var);

 #define DECLARE_STATIC_METHOD(dst_var, cls, name, signature) \
      static jmethodID dst_var = NULL; \
      GET_STATIC_METHOD(dst_var, cls, name, signature);

 #define GET_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetStaticMethodID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL_RETURN(dst_var, ret);

 #define DECLARE_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret) \
      static jmethodID dst_var = NULL; \
      GET_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret);

 /********        GET FIELD SUPPORT    *********/


 #define GET_FIELD(dst_var, cls, name, signature) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetFieldID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL(dst_var);

 #define DECLARE_FIELD(dst_var, cls, name, signature) \
      static jfieldID dst_var = NULL; \
      GET_FIELD(dst_var, cls, name, signature);

 #define GET_FIELD_RETURN(dst_var, cls, name, signature, ret) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetFieldID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL_RETURN(dst_var, ret);

 #define DECLARE_FIELD_RETURN(dst_var, cls, name, signature, ret) \
      static jfieldID dst_var = NULL; \
      GET_FIELD_RETURN(dst_var, cls, name, signature, ret);

 #define GET_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret) \
      if (dst_var == NULL) { \
          dst_var = (*env)->GetStaticFieldID(env, cls, name, signature); \
      } \
      LOG_NULL(dst_var, name); \
      CHECK_NULL_RETURN(dst_var, ret);

 #define DECLARE_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret) \
      static jfieldID dst_var = NULL; \
      GET_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret);

 /*********       EXCEPTION_HANDLING    *********/

 /*
  * Some explanation to set context of the bigger picture.
  * Before returning to Java from JNI, NSExceptions are caught - so long as
  * the body of the native method is wrapped in the ENTER/EXIT macros.
  * So if we want to directly return to Java from some nested Objective-C
  * function when detecting a Java exception, we just need to raise an
  * NSException. Then clear that right before returning to Java,
  * leaving the Java exception to be seen back in Java-land.
  *
  * But if the current thread is the Appkit thread we might as well clear
  * the Java Exception right now since there's nothing to receive it.
  * In such a case control will propagate back to the run loop which might
  * terminate the application. One drawback of that is that the location of
  * termination does not show where the NSException originated.
  * And for whatever reason, something swallows that exception.
  * So as a debugging aid, when on the AppKit thread we can provide a
  * way (via an env. var.) to log the location.
  * Additionally provide a similar way to prevent the NSException being
  * raised and instead just clear the Java Exception.
  * Together these provide alternate behaviours for more debugging info
  * or maybe a way for the app to continue running depending on the exact
  * nature of the problem that has been detected and how survivable it is.
  */
 #define CHECK_EXCEPTION() \
     if ((*env)->ExceptionOccurred(env) != NULL) { \
         if ([NSThread isMainThread] == YES) { \
             if (getenv("JNU_APPKIT_TRACE")) { \
                 (*env)->ExceptionDescribe(env); \
                 NSLog(@"%@",[NSThread callStackSymbols]); \
               } else { \
                   (*env)->ExceptionClear(env); \
               } \
          }  \
         if (getenv("JNU_NO_COCOA_EXCEPTION") == NULL) { \
             [NSException raise:NSGenericException format:@"Java Exception"]; \
         } else { \
             (*env)->ExceptionClear(env); \
         } \
     };

 #define CHECK_EXCEPTION_NULL_RETURN(x, y) \
     CHECK_EXCEPTION(); \
     if ((x) == NULL) { \
        return y; \
     };

 /* Create a pool and initiate a try block to catch any exception */
 #define JNI_COCOA_ENTER(env) \
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; \
  @try {

 /* Don't allow NSExceptions to escape to Java.
  * If there is a Java exception that has been thrown that should escape.
  * And ensure we drain the auto-release pool.
  */
 #define JNI_COCOA_EXIT(env) \
  } \
  @catch (NSException *e) { \
      NSLog(@"%@", [e callStackSymbols]); \
  } \
  @finally { \
     [pool drain]; \
  };

 /* Same as above but adds a clean up action.
  * Requires that whatever is being cleaned up is in scope.
  */
 #define JNI_COCOA_EXIT_WITH_ACTION(env, action) \
  } \
  @catch (NSException *e) { \
      { action; }; \
      NSLog(@"%@", [e callStackSymbols]); \
  } \
  @finally { \
     [pool drain]; \
  };

 /********        STRING CONVERSION SUPPORT    *********/

 JNIEXPORT NSString* JavaStringToNSString(JNIEnv *env, jstring jstr);

 JNIEXPORT jstring NSStringToJavaString(JNIEnv* env, NSString *str);

 JNIEXPORT NSString* NormalizedPathNSStringFromJavaString(JNIEnv *env, jstring pathStr);

 JNIEXPORT jstring NormalizedPathJavaStringFromNSString(JNIEnv* env, NSString *str);

 #endif /* __JNIUTILITIES_H */
	/*
	* Copyright (c) 2020, 2021, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	#ifndef __JNIUTILITIES_H
	#define __JNIUTILITIES_H

	#include "jni.h"
	#include "jni_util.h"

	#import <Cocoa/Cocoa.h>

	/****** LOGGING SUPPORT *******/

	#define LOG_NULL(dst_var, name) \
	if (dst_var == NULL) { \
	NSLog(@"Bad JNI lookup %s\n", name); \
	NSLog(@"%@",[NSThread callStackSymbols]); \
	if ([NSThread isMainThread] == NO) { \
	if ((*env)->ExceptionOccurred(env) == NULL) { \
	JNU_ThrowInternalError(env, "Bad JNI Lookup"); \
	} \
	} else { \
	if ((*env)->ExceptionOccurred(env) != NULL) { \
	(*env)->ExceptionDescribe(env); \
	} \
	} \
	[NSException raise:NSGenericException format:@"JNI Lookup Exception"]; \
	}

	/****** GET CLASS SUPPORT *******/

	#define GET_CLASS(dst_var, cls) \
	if (dst_var == NULL) { \
	dst_var = (*env)->FindClass(env, cls); \
	if (dst_var != NULL) dst_var = (*env)->NewGlobalRef(env, dst_var); \
	} \
	LOG_NULL(dst_var, cls); \
	CHECK_NULL(dst_var);

	#define DECLARE_CLASS(dst_var, cls) \
	static jclass dst_var = NULL; \
	GET_CLASS(dst_var, cls);

	#define GET_CLASS_RETURN(dst_var, cls, ret) \
	if (dst_var == NULL) { \
	dst_var = (*env)->FindClass(env, cls); \
	if (dst_var != NULL) dst_var = (*env)->NewGlobalRef(env, dst_var); \
	} \
	LOG_NULL(dst_var, cls); \
	CHECK_NULL_RETURN(dst_var, ret);

	#define DECLARE_CLASS_RETURN(dst_var, cls, ret) \
	static jclass dst_var = NULL; \
	GET_CLASS_RETURN(dst_var, cls, ret);


	/****** GET METHOD SUPPORT *******/

	#define GET_METHOD(dst_var, cls, name, signature) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetMethodID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL(dst_var);

	#define DECLARE_METHOD(dst_var, cls, name, signature) \
	static jmethodID dst_var = NULL; \
	GET_METHOD(dst_var, cls, name, signature);

	#define GET_METHOD_RETURN(dst_var, cls, name, signature, ret) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetMethodID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL_RETURN(dst_var, ret);

	#define DECLARE_METHOD_RETURN(dst_var, cls, name, signature, ret) \
	static jmethodID dst_var = NULL; \
	GET_METHOD_RETURN(dst_var, cls, name, signature, ret);

	#define GET_STATIC_METHOD(dst_var, cls, name, signature) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetStaticMethodID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL(dst_var);

	#define DECLARE_STATIC_METHOD(dst_var, cls, name, signature) \
	static jmethodID dst_var = NULL; \
	GET_STATIC_METHOD(dst_var, cls, name, signature);

	#define GET_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetStaticMethodID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL_RETURN(dst_var, ret);

	#define DECLARE_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret) \
	static jmethodID dst_var = NULL; \
	GET_STATIC_METHOD_RETURN(dst_var, cls, name, signature, ret);

	/****** GET FIELD SUPPORT *******/


	#define GET_FIELD(dst_var, cls, name, signature) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetFieldID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL(dst_var);

	#define DECLARE_FIELD(dst_var, cls, name, signature) \
	static jfieldID dst_var = NULL; \
	GET_FIELD(dst_var, cls, name, signature);

	#define GET_FIELD_RETURN(dst_var, cls, name, signature, ret) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetFieldID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL_RETURN(dst_var, ret);

	#define DECLARE_FIELD_RETURN(dst_var, cls, name, signature, ret) \
	static jfieldID dst_var = NULL; \
	GET_FIELD_RETURN(dst_var, cls, name, signature, ret);

	#define GET_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret) \
	if (dst_var == NULL) { \
	dst_var = (*env)->GetStaticFieldID(env, cls, name, signature); \
	} \
	LOG_NULL(dst_var, name); \
	CHECK_NULL_RETURN(dst_var, ret);

	#define DECLARE_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret) \
	static jfieldID dst_var = NULL; \
	GET_STATIC_FIELD_RETURN(dst_var, cls, name, signature, ret);

	/******* EXCEPTION_HANDLING *******/

	/*
	* Some explanation to set context of the bigger picture.
	* Before returning to Java from JNI, NSExceptions are caught - so long as
	* the body of the native method is wrapped in the ENTER/EXIT macros.
	* So if we want to directly return to Java from some nested Objective-C
	* function when detecting a Java exception, we just need to raise an
	* NSException. Then clear that right before returning to Java,
	* leaving the Java exception to be seen back in Java-land.
	*
	* But if the current thread is the Appkit thread we might as well clear
	* the Java Exception right now since there's nothing to receive it.
	* In such a case control will propagate back to the run loop which might
	* terminate the application. One drawback of that is that the location of
	* termination does not show where the NSException originated.
	* And for whatever reason, something swallows that exception.
	* So as a debugging aid, when on the AppKit thread we can provide a
	* way (via an env. var.) to log the location.
	* Additionally provide a similar way to prevent the NSException being
	* raised and instead just clear the Java Exception.
	* Together these provide alternate behaviours for more debugging info
	* or maybe a way for the app to continue running depending on the exact
	* nature of the problem that has been detected and how survivable it is.
	*/
	#define CHECK_EXCEPTION() \
	if ((*env)->ExceptionOccurred(env) != NULL) { \
	if ([NSThread isMainThread] == YES) { \
	if (getenv("JNU_APPKIT_TRACE")) { \
	(*env)->ExceptionDescribe(env); \
	NSLog(@"%@",[NSThread callStackSymbols]); \
	} else { \
	(*env)->ExceptionClear(env); \
	} \
	} \
	if (getenv("JNU_NO_COCOA_EXCEPTION") == NULL) { \
	[NSException raise:NSGenericException format:@"Java Exception"]; \
	} else { \
	(*env)->ExceptionClear(env); \
	} \
	};

	#define CHECK_EXCEPTION_NULL_RETURN(x, y) \
	CHECK_EXCEPTION(); \
	if ((x) == NULL) { \
	return y; \
	};

	/* Create a pool and initiate a try block to catch any exception */
	#define JNI_COCOA_ENTER(env) \
	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; \
	@try {

	/* Don't allow NSExceptions to escape to Java.
	* If there is a Java exception that has been thrown that should escape.
	* And ensure we drain the auto-release pool.
	*/
	#define JNI_COCOA_EXIT(env) \
	} \
	@catch (NSException *e) { \
	NSLog(@"%@", [e callStackSymbols]); \
	} \
	@finally { \
	[pool drain]; \
	};

	/* Same as above but adds a clean up action.
	* Requires that whatever is being cleaned up is in scope.
	*/
	#define JNI_COCOA_EXIT_WITH_ACTION(env, action) \
	} \
	@catch (NSException *e) { \
	{ action; }; \
	NSLog(@"%@", [e callStackSymbols]); \
	} \
	@finally { \
	[pool drain]; \
	};

	/****** STRING CONVERSION SUPPORT *******/

	JNIEXPORT NSString* JavaStringToNSString(JNIEnv *env, jstring jstr);

	JNIEXPORT jstring NSStringToJavaString(JNIEnv* env, NSString *str);

	JNIEXPORT NSString* NormalizedPathNSStringFromJavaString(JNIEnv *env, jstring pathStr);

	JNIEXPORT jstring NormalizedPathJavaStringFromNSString(JNIEnv* env, NSString *str);

	#endif /* __JNIUTILITIES_H */