Add JNI code

dreiss · dreiss · commit fcef9bdba2f1 · 2018-01-18T16:32:23.000-08:00
Now all of the major modules have a JNI component.
diff --git a/src/com/facebook/example/animals/BUCK b/src/com/facebook/example/animals/BUCK
@@ -3,6 +3,7 @@ android_library(
     manifest = "manifest.xml",
     srcs = glob(["*.java"]),
     deps = [
+        "//src/com/facebook/example/animals/jni:jni",
         "//src/com/facebook/example/habitat:habitat",
         "//src/com/facebook/example/mammals:mammals",
     ],
diff --git a/src/com/facebook/example/animals/Penguin.java b/src/com/facebook/example/animals/Penguin.java
@@ -19,11 +19,13 @@
 import com.facebook.example.habitat.Ice;
 
 public class Penguin {
+  static {
+    System.loadLibrary("animals");
+  }
+
   public static String getDescription() {
     return getName() + " on " + Ice.getName();
   }
 
-  private static String getName() {
-    return "penguin";
-  }
+  private static native String getName();
 }
diff --git a/src/com/facebook/example/animals/jni/BUCK b/src/com/facebook/example/animals/jni/BUCK
@@ -0,0 +1,8 @@
+cxx_library(
+    name = "jni",
+    soname = "libanimals.$(ext)",
+    srcs = glob(["*.c"]),
+    visibility = [
+        "//src/com/facebook/example/animals:animals",
+    ],
+)
diff --git a/src/com/facebook/example/animals/jni/animals.c b/src/com/facebook/example/animals/jni/animals.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018-present, Facebook, Inc.
+ *
+ * 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 <stddef.h>
+#include <jni.h>
+
+static jstring nativeGetName(JNIEnv* env, jclass cls) {
+  return (*env)->NewStringUTF(env, "penguin");
+}
+
+JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+  JNIEnv* env;
+  if ((*vm)->GetEnv(vm, (void**)&env, JNI_VERSION_1_6)) {
+    return JNI_ERR;
+  }
+
+  jclass penguinClass = (*env)->FindClass(env, "com/facebook/example/animals/Penguin");
+  if (penguinClass == NULL) {
+    return JNI_ERR;
+  }
+  JNINativeMethod methods[] = {
+    {"getName", "()Ljava/lang/String;", nativeGetName},
+  };
+  size_t nMethods = sizeof(methods) / sizeof(methods[0]);
+  jint result = (*env)->RegisterNatives(env, penguinClass, methods, nMethods);
+  if (result != 0) {
+    return JNI_ERR;
+  }
+
+  return JNI_VERSION_1_6;
+}
diff --git a/src/com/facebook/example/habitat/BUCK b/src/com/facebook/example/habitat/BUCK
@@ -2,6 +2,7 @@ java_library(
     name = "habitat",
     srcs = glob(["*.java"]),
     deps = [
+        "//src/com/facebook/example/habitat/jni:jni",
     ],
     visibility = ["PUBLIC"],
 )
diff --git a/src/com/facebook/example/habitat/Ice.java b/src/com/facebook/example/habitat/Ice.java
@@ -17,9 +17,11 @@
 package com.facebook.example.habitat;
 
 public class Ice {
+  static {
+    System.loadLibrary("habitat");
+  }
+
   private static int dxWorkaround = 0;
 
-  public static String getName() {
-    return "ice";
-  }
+  public static native String getName();
 }
diff --git a/src/com/facebook/example/habitat/jni/BUCK b/src/com/facebook/example/habitat/jni/BUCK
@@ -0,0 +1,8 @@
+cxx_library(
+    name = "jni",
+    soname = "libhabitat.$(ext)",
+    srcs = glob(["*.c"]),
+    visibility = [
+        "//src/com/facebook/example/habitat:habitat",
+    ],
+)
diff --git a/src/com/facebook/example/habitat/jni/habitat.c b/src/com/facebook/example/habitat/jni/habitat.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018-present, Facebook, Inc.
+ *
+ * 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 <stddef.h>
+#include <jni.h>
+
+static jstring nativeGetName(JNIEnv* env, jclass cls) {
+  return (*env)->NewStringUTF(env, "ice");
+}
+
+JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+  JNIEnv* env;
+  if ((*vm)->GetEnv(vm, (void**)&env, JNI_VERSION_1_6)) {
+    return JNI_ERR;
+  }
+
+  jclass iceClass = (*env)->FindClass(env, "com/facebook/example/habitat/Ice");
+  if (iceClass == NULL) {
+    return JNI_ERR;
+  }
+  JNINativeMethod methods[] = {
+    {"getName", "()Ljava/lang/String;", nativeGetName},
+  };
+  size_t nMethods = sizeof(methods) / sizeof(methods[0]);
+  jint result = (*env)->RegisterNatives(env, iceClass, methods, nMethods);
+  if (result != 0) {
+    return JNI_ERR;
+  }
+
+  return JNI_VERSION_1_6;
+}
diff --git a/src/com/facebook/example/mammals/BUCK b/src/com/facebook/example/mammals/BUCK
@@ -2,6 +2,7 @@ java_library(
     name = "mammals",
     srcs = glob(["*.java"]),
     deps = [
+        "//src/com/facebook/example/mammals/jni:jni",
     ],
     visibility = ["PUBLIC"],
 )
diff --git a/src/com/facebook/example/mammals/SeaLion.java b/src/com/facebook/example/mammals/SeaLion.java
@@ -17,11 +17,13 @@
 package com.facebook.example.mammals;
 
 public class SeaLion {
+  static {
+    System.loadLibrary("mammals");
+  }
+
   public static String getDescription() {
     return "just a " + getName();
   }
 
-  private static String getName() {
-    return "sea lion";
-  }
+  private static native String getName();
 }
diff --git a/src/com/facebook/example/mammals/jni/BUCK b/src/com/facebook/example/mammals/jni/BUCK
@@ -0,0 +1,8 @@
+cxx_library(
+    name = "jni",
+    soname = "libmammals.$(ext)",
+    srcs = glob(["*.c"]),
+    visibility = [
+        "//src/com/facebook/example/mammals:mammals",
+    ],
+)
diff --git a/src/com/facebook/example/mammals/jni/mammals.c b/src/com/facebook/example/mammals/jni/mammals.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018-present, Facebook, Inc.
+ *
+ * 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 <stddef.h>
+#include <jni.h>
+
+static jstring nativeGetName(JNIEnv* env, jclass cls) {
+  return (*env)->NewStringUTF(env, "sea lion");
+}
+
+JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+  JNIEnv* env;
+  if ((*vm)->GetEnv(vm, (void**)&env, JNI_VERSION_1_6)) {
+    return JNI_ERR;
+  }
+
+  jclass seaLionClass = (*env)->FindClass(env, "com/facebook/example/mammals/SeaLion");
+  if (seaLionClass == NULL) {
+    return JNI_ERR;
+  }
+  JNINativeMethod methods[] = {
+    {"getName", "()Ljava/lang/String;", nativeGetName},
+  };
+  size_t nMethods = sizeof(methods) / sizeof(methods[0]);
+  jint result = (*env)->RegisterNatives(env, seaLionClass, methods, nMethods);
+  if (result != 0) {
+    return JNI_ERR;
+  }
+
+  return JNI_VERSION_1_6;
+}
