1 files changed, 52 insertions, 0 deletions
diff --git a/third_party/java/proguard/proguard5.3.3/examples/annotations/examples/NativeCallBack.java b/third_party/java/proguard/proguard5.3.3/examples/annotations/examples/NativeCallBack.java
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index 0000000000..a4e5583e18
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+++ b/third_party/java/proguard/proguard5.3.3/examples/annotations/examples/NativeCallBack.java
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+import proguard.annotation.*;
+
+/**
+ * This application illustrates the use of annotations for configuring ProGuard.
+ *
+ * You can compile it with:
+ *     javac -classpath ../lib/annotations.jar NativeCallBack.java
+ * You can then process it with:
+ *     java -jar ../../../lib/proguard.jar @ ../examples.pro
+ *
+ * The annotation will preserve the class and its main method,
+ * as a result of the specifications in lib/annotations.pro.
+ */
+@KeepApplication
+public class NativeCallBack
+{
+    /**
+     * Suppose this is a native method that computes an answer.
+     *
+     * The -keep option for native methods in the regular ProGuard
+     * configuration will make sure it is not removed or renamed when
+     * processing this code.
+     */
+    public native int computeAnswer();
+
+
+    /**
+     * Suppose this method is called back from the above native method.
+     *
+     * ProGuard would remove it, because it is not referenced from java.
+     * The annotation will make sure it is preserved anyhow.
+     */
+    @Keep
+    public int getAnswer()
+    {
+        return 42;
+    }
+
+
+    /**
+     * The main entry point of the application.
+     *
+     * The @KeepApplication annotation of this class will make sure it is not
+     * removed or renamed when processing this code.
+     */
+    public static void main(String[] args)
+    {
+        int answer = new NativeCallBack().computeAnswer();
+
+        System.out.println("The answer is " + answer);
+    }
+}