| /* |
| * Copyright (c) 2018, 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. |
| * |
| * 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. |
| */ |
| |
| #include <jni.h> |
| |
| // boolean flag for static versus non-static |
| #define STATIC 1 |
| #define NON_STATIC 0 |
| |
| // Helper methods to get class/method/field IDs |
| |
| static void getClassID(JNIEnv *env, |
| jstring defining_class_name, |
| jclass* clazz) { |
| const char* name = (*env)->GetStringUTFChars(env, defining_class_name, NULL); |
| if (name != NULL) { |
| *clazz = (*env)->FindClass(env, name); |
| (*env)->ReleaseStringUTFChars(env, defining_class_name, name); |
| } |
| } |
| |
| static void getClassAndMethodID(JNIEnv *env, |
| int is_static, |
| jstring defining_class_name, |
| jstring method_name, |
| const char* sig, |
| jmethodID* m_id, jclass* clazz) { |
| getClassID(env, defining_class_name, clazz); |
| if (*clazz != NULL) { |
| const char* name = (*env)->GetStringUTFChars(env, method_name, NULL); |
| if (name != NULL) { |
| if (is_static) { |
| *m_id = (*env)->GetStaticMethodID(env, *clazz, name, sig); |
| } else { |
| *m_id = (*env)->GetMethodID(env, *clazz, name, sig); |
| } |
| (*env)->ReleaseStringUTFChars(env, method_name, name); |
| } |
| } |
| } |
| |
| static void getClassAndFieldID(JNIEnv *env, |
| int is_static, |
| jstring defining_class_name, |
| jstring field_name, |
| const char* sig, |
| jfieldID* m_id, jclass* clazz) { |
| getClassID(env, defining_class_name, clazz); |
| if (*clazz != NULL) { |
| const char* name = (*env)->GetStringUTFChars(env, field_name, NULL); |
| if (name != NULL) { |
| if (is_static) { |
| *m_id = (*env)->GetStaticFieldID(env, *clazz, name, sig); |
| } else { |
| *m_id = (*env)->GetFieldID(env, *clazz, name, sig); |
| } |
| (*env)->ReleaseStringUTFChars(env, field_name, name); |
| } |
| } |
| } |
| |
| JNIEXPORT void JNICALL |
| Java_NestmatesJNI_callVoidVoid(JNIEnv *env, jclass unused, |
| jobject target, |
| jstring defining_class_name, |
| jstring method_name, |
| jboolean virtual) { |
| |
| // Lookup "void method_name()" in defining_class_name, and if it exists |
| // call target.method_name() using a virtual or non-virtual invocation |
| |
| jmethodID m_id = NULL; |
| jclass clazz = NULL; |
| getClassAndMethodID(env, NON_STATIC, defining_class_name, method_name, |
| "()V", &m_id, &clazz); |
| if (m_id != NULL && clazz != NULL) { |
| if (!virtual) { |
| (*env)->CallNonvirtualVoidMethod(env, target, clazz, m_id); |
| } else { |
| (*env)->CallVoidMethod(env, target, m_id); |
| } |
| } |
| } |
| |
| JNIEXPORT jobject JNICALL |
| Java_NestmatesJNI_callStringVoid(JNIEnv *env, jclass unused, |
| jobject target, |
| jstring defining_class_name, |
| jstring method_name, |
| jboolean virtual) { |
| |
| // Lookup "String method_name()" in defining_class_name, and if it exists |
| // call target.method_name() using a virtual or non-virtual invocation |
| |
| jmethodID m_id = NULL; |
| jclass clazz = NULL; |
| getClassAndMethodID(env, NON_STATIC, defining_class_name, method_name, |
| "()Ljava/lang/String;", &m_id, &clazz); |
| if (m_id != NULL && clazz != NULL) { |
| if (!virtual) { |
| return (*env)->CallNonvirtualObjectMethod(env, target, clazz, m_id); |
| } else { |
| return (*env)->CallObjectMethod(env, target, m_id); |
| } |
| } |
| return NULL; |
| } |
| |
| JNIEXPORT jobject JNICALL |
| Java_NestmatesJNI_newInstance0(JNIEnv *env, jclass unused, |
| jstring defining_class_name, |
| jstring method_name, |
| jstring sig, |
| jobject outerThis) { |
| |
| // Lookup the no-user-arg constructor in defining_class_name using sig, |
| // and use it to create an instance of the class, and return it. For |
| // inner classes we need an outerThis reference to pass to the constructor. |
| |
| jmethodID m_id = NULL; |
| jclass clazz = NULL; |
| const char* _sig = (*env)->GetStringUTFChars(env, sig, NULL); |
| getClassAndMethodID(env, NON_STATIC, defining_class_name, method_name, |
| _sig, &m_id, &clazz); |
| (*env)->ReleaseStringUTFChars(env, sig, _sig); |
| if (m_id != NULL && clazz != NULL) { |
| return (*env)->NewObject(env, clazz, m_id, outerThis); |
| } |
| return NULL; |
| } |
| |
| JNIEXPORT void JNICALL |
| Java_NestmatesJNI_callStaticVoidVoid(JNIEnv *env, jclass unused, |
| jstring defining_class_name, |
| jstring method_name) { |
| |
| // Lookup "static void method_name()" in defining_class_name, and if it exists |
| // invoke it. |
| |
| jmethodID m_id = NULL; |
| jclass clazz = NULL; |
| getClassAndMethodID(env, STATIC, defining_class_name, method_name, |
| "()V", &m_id, &clazz); |
| if (m_id != NULL && clazz != NULL) { |
| (*env)->CallStaticVoidMethod(env, clazz, m_id); |
| } |
| } |
| |
| JNIEXPORT jint JNICALL |
| Java_NestmatesJNI_getIntField(JNIEnv *env, jclass unused, |
| jobject target, |
| jstring defining_class_name, |
| jstring field_name) { |
| |
| // Lookup field field_name in defining_class_name, and if it exists |
| // return its value. |
| |
| jfieldID f_id = NULL; |
| jclass clazz = NULL; |
| getClassAndFieldID(env, NON_STATIC, defining_class_name, field_name, |
| "I", &f_id, &clazz); |
| if (f_id != NULL && clazz != NULL) { |
| return (*env)->GetIntField(env, target, f_id); |
| } |
| return -1; |
| } |
| |
| JNIEXPORT void JNICALL |
| Java_NestmatesJNI_setIntField(JNIEnv *env, jclass unused, |
| jobject target, |
| jstring defining_class_name, |
| jstring field_name, |
| jint newVal) { |
| |
| // Lookup field field_name in defining_class_name, and if it exists |
| // set it to newVal. |
| |
| jfieldID f_id = NULL; |
| jclass clazz = NULL; |
| getClassAndFieldID(env, NON_STATIC, defining_class_name, field_name, |
| "I", &f_id, &clazz); |
| if (f_id != NULL && clazz != NULL) { |
| (*env)->SetIntField(env, target, f_id, newVal); |
| } |
| } |
| |
| JNIEXPORT jint JNICALL |
| Java_NestmatesJNI_getStaticIntField(JNIEnv *env, jclass unused, |
| jstring defining_class_name, |
| jstring field_name) { |
| |
| // Lookup field field_name in defining_class_name, and if it exists |
| // return its value. |
| |
| jfieldID f_id = NULL; |
| jclass clazz = NULL; |
| getClassAndFieldID(env, STATIC, defining_class_name, field_name, |
| "I", &f_id, &clazz); |
| if (f_id != NULL && clazz != NULL) { |
| return (*env)->GetStaticIntField(env, clazz, f_id); |
| } |
| return -1; |
| } |
| |
| JNIEXPORT void JNICALL |
| Java_NestmatesJNI_setStaticIntField(JNIEnv *env, jclass unused, |
| jstring defining_class_name, |
| jstring field_name, |
| jint newVal) { |
| |
| // Lookup field field_name in defining_class_name, and if it exists |
| // set it to newVal. |
| |
| jfieldID f_id = NULL; |
| jclass clazz = NULL; |
| getClassAndFieldID(env, STATIC, defining_class_name, field_name, |
| "I", &f_id, &clazz); |
| if (f_id != NULL && clazz != NULL) { |
| (*env)->SetStaticIntField(env, clazz, f_id, newVal); |
| } |
| } |
