Cache jclass/jmethodID/jfieldID references

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

diff --git a/vpp-japi/japi/vppjni_env.c b/vpp-japi/japi/vppjni_env.c
new file mode 100644 (file)
index 0000000..84991ee
--- /dev/null
+++ b/vpp-japi/japi/vppjni_env.c
@@ -0,0 +1,111 @@
+/*
+ * 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.
+ */
+#include <jni.h>
+
+#include "vppjni_env.h"
+
+// Head of the class registration list.
+static vppjni_class_t *class_head;
+// Head of the class registration list.
+static vppjni_field_t *field_head;
+
+void vppjni_init_register_class(vppjni_class_t *ptr)
+{
+    vppjni_class_t **where = &class_head;
+    while (*where != NULL) {
+        where = &((*where)->next);
+    }
+    *where = ptr;
+}
+
+void vppjni_register_field(vppjni_field_t *ptr) {
+    vppjni_field_t **where = &field_head;
+    while (*where != NULL) {
+        where = &((*where)->next);
+    }
+    *where = ptr;
+}
+
+jobject vppjni_init_new_object(JNIEnv *env, const vppjni_class_t *ptr, va_list ap) {
+    jobject obj = (*env)->NewObjectV(env, ptr->jclass, ptr->jinit, ap);
+    if ((*env)->ExceptionCheck(env)) {
+        (*env)->ExceptionDescribe(env);
+        return NULL;
+    }
+
+    return obj;
+}
+
+int vppjni_env_init(JNIEnv *env)
+{
+    vppjni_class_t *cwlk;
+    vppjni_field_t *fwlk;
+
+    for (cwlk = class_head; cwlk != NULL; cwlk = cwlk->next) {
+        jclass cls;
+        jmethodID method;
+
+        cls = (*env)->FindClass(env, cwlk->fqcn);
+        if ((*env)->ExceptionCheck(env)) {
+            (*env)->ExceptionDescribe(env);
+            vppjni_uninit(env);
+            return JNI_ERR;
+        }
+
+        method = (*env)->GetMethodID(env, cls, "<init>", cwlk->init_sig);
+        if ((*env)->ExceptionCheck(env)) {
+            (*env)->ExceptionDescribe(env);
+            vppjni_uninit(env);
+            return JNI_ERR;
+        }
+
+        cwlk->jclass = (*env)->NewGlobalRef(env, cls);
+        if (cwlk->jclass == NULL) {
+            vppjni_uninit(env);
+            return JNI_ERR;
+        }
+        cwlk->jinit = method;
+    }
+
+    for (fwlk = field_head; fwlk != NULL; fwlk = fwlk->next) {
+        fwlk->jfield = (*env)->GetFieldID(env, fwlk->clsref->jclass, fwlk->name, fwlk->type);
+        if ((*env)->ExceptionCheck(env)) {
+            (*env)->ExceptionDescribe(env);
+            vppjni_uninit(env);
+            return JNI_ERR;
+        }
+    }
+
+    return 0;
+}
+
+void vppjni_env_uninit(JNIEnv *env) {
+    vppjni_class_t *cwlk;
+    vppjni_field_t *fwlk;
+
+    for (fwlk = field_head; fwlk != NULL; fwlk = fwlk->next) {
+        fwlk->jfield = NULL;
+    }
+
+    for (cwlk = class_head; cwlk != NULL; cwlk = cwlk->next) {
+        if (cwlk->jclass != NULL ) {
+            (*env)->DeleteGlobalRef(env, cwlk->jclass);
+        }
+
+        cwlk->jclass = NULL;
+        cwlk->jinit = NULL;
+    }
+}
+