Cache jclass/jmethodID/jfieldID references

[vpp.git] / vpp-japi / japi / vppjni_env.h

diff --git a/vpp-japi/japi/vppjni_env.h b/vpp-japi/japi/vppjni_env.h
new file mode 100644 (file)
index 0000000..fe9767b
--- /dev/null
+++ b/vpp-japi/japi/vppjni_env.h
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Utilities for accessing Java classes/method/fields in an efficient
+ * manner.
+ */
+
+/*
+ * A potentially-uninitialized reference to a Java class
+ */
+typedef struct vppjni_class {
+    // Fully-Qualified Class Name
+    const char          *fqcn;
+    // Constructor signature
+    const char          *init_sig;
+    // Global reference to class handle
+    jclass              jclass;
+    // Constructor method handle
+    jmethodID           jinit;
+    // Next item in linked list
+    struct vppjni_class *next;
+} vppjni_class_t;
+
+typedef struct jenv_field {
+    // Field name
+    const char           *name;
+    // Field type
+    const char           *type;
+    // Defining class reference
+    const vppjni_class_t *clsref;
+    // Field handle
+    jfieldID             jfield;
+    // Next item in linked list
+    struct jenv_field    *next;
+} vppjni_field_t;
+
+#define VPPJNI_CLASS_SYMBOL(name) vppjni_class_##name
+#define VPPJNI_CLASS_INIT(name) vppjni_class_##name##_init
+#define BIND_JAPI_CLASS(name, sig) \
+    static vppjni_class_t VPPJNI_CLASS_SYMBOL(name); \
+    static void VPPJNI_CLASS_INIT(name)(void) __attribute__((__constructor__)); \
+    static void VPPJNI_CLASS_INIT(name)() \
+    { \
+        VPPJNI_CLASS_SYMBOL(name).fqcn = "org/openvpp/vppjapi/" #name; \
+        VPPJNI_CLASS_SYMBOL(name).init_sig = sig; \
+        vppjni_register_class(&VPPJNI_CLASS_SYMBOL(name)); \
+    } \
+    static __attribute__((unused)) jobject name##Array(JNIEnv *env, jsize length) \
+    { \
+        return (*env)->NewObjectArray(env, length, VPPJNI_CLASS_SYMBOL(name).jclass, NULL); \
+    } \
+    static jobject name##Object(JNIEnv *env, ...) \
+    { \
+        va_list ap; \
+        va_start(ap, env); \
+        jobject obj = vppjni_new_object(env, &VPPJNI_CLASS_SYMBOL(name), ap); \
+        va_end(ap); \
+        return obj; \
+    }
+
+#define VPPJNI_FIELD_SYMBOL(cls, name) vppjni_field_##cls##_##name
+#define VPPJNI_FIELD_INIT(cls, name) vppjni_field_##cls##_##name##_init
+#define BIND_JAPI_FIELD(cls, field, sig) \
+    static vppjni_field_t VPPJNI_FIELD_SYMBOL(cls, field); \
+        static void VPPJNI_FIELD_INIT(cls, field)(void) __attribute__((__constructor__)); \
+    static void VPPJNI_FIELD_INIT(cls, field)() \
+    { \
+        VPPJNI_FIELD_SYMBOL(cls, field).name = #field; \
+        VPPJNI_FIELD_SYMBOL(cls, field).type = sig; \
+        VPPJNI_FIELD_SYMBOL(cls, field).clsref = &VPPJNI_CLASS_SYMBOL(cls); \
+        vppjni_register_field(&VPPJNI_FIELD_SYMBOL(cls, field)); \
+    }
+#define BIND_JAPI_BOOL_FIELD(cls, field) \
+    BIND_JAPI_FIELD(cls, field, "Z"); \
+    static void set_##cls##_##field(JNIEnv *env, jobject obj, jboolean value) \
+    { \
+        (*env)->SetBooleanField(env, obj, VPPJNI_FIELD_SYMBOL(cls, field).jfield, value); \
+    }
+#define BIND_JAPI_BYTE_FIELD(cls, field) \
+    BIND_JAPI_FIELD(cls, field, "B"); \
+    static void set_##cls##_##field(JNIEnv *env, jobject obj, jbyte value) \
+    { \
+        (*env)->SetByteField(env, obj, VPPJNI_FIELD_SYMBOL(cls, field).jfield, value); \
+    }
+#define BIND_JAPI_INT_FIELD(cls, field) \
+    BIND_JAPI_FIELD(cls, field, "I"); \
+    static void set_##cls##_##field(JNIEnv *env, jobject obj, jint value) \
+    { \
+        (*env)->SetIntField(env, obj, VPPJNI_FIELD_SYMBOL(cls, field).jfield, value); \
+    }
+#define BIND_JAPI_OBJ_FIELD(cls, field, sig) \
+    BIND_JAPI_FIELD(cls, field, sig); \
+    static void set_##cls##_##field(JNIEnv *env, jobject obj, jobject value) \
+    { \
+        (*env)->SetObjectField(env, obj, VPPJNI_FIELD_SYMBOL(cls, field).jfield, value); \
+    }
+#define BIND_JAPI_STRING_FIELD(cls, field) \
+    BIND_JAPI_OBJ_FIELD(cls, field, "Ljava/lang/String;")
+
+jobject vppjni_new_object(JNIEnv *env, const vppjni_class_t *ptr, va_list ap);
+void vppjni_register_class(vppjni_class_t *ptr);
+void vppjni_register_field(vppjni_field_t *ptr);
+int vppjni_init(JNIEnv *env);
+void vppjni_uninit(JNIEnv *env);
+