[#8890] Temporary: forcefully bind Java9ClassLoader in System.bootLayer

pinpoint-apm · Jun 2, 2022 · 536710d · 536710d
1 parent ad1d936
commit 536710d
Showing 1 changed file with 34 additions and 0 deletions.
diff --git a/...a9/src/main/java/com/navercorp/pinpoint/bootstrap/java9/classloader/Java9ClassLoader.java b/...a9/src/main/java/com/navercorp/pinpoint/bootstrap/java9/classloader/Java9ClassLoader.java
@@ -18,6 +18,8 @@
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.Enumeration;
@@ -45,6 +47,38 @@ public Java9ClassLoader(String name, URL[] urls, ClassLoader parent, List<String
         Objects.requireNonNull(libClass, "libClass");
 
         this.profilerLibClass = new ProfilerLibClass(libClass);
+
+        TEMPORARY_bindClassLoaderToBootLayerInOpenJ9(this);
+    }
+
+    /**
+     * It forcefully executes `System.bootLayer.bindToLoader(classLoader)` in openj9
+     * @param classLoader classLoader to bind to bootLayer
+     */
+    private void TEMPORARY_bindClassLoaderToBootLayerInOpenJ9(ClassLoader classLoader) {
+        final String vmName = System.getProperty("java.vm.name");
+        if (!vmName.toLowerCase().contains("openj9")) {
+            System.out.printf("java.vm.name: %s, skip binding Java9ClassLoader to bootLayer\n", vmName);
+            return;
+        } else {
+            System.out.printf("java.vm.name: %s, binding Java9ClassLoader to bootLayer\n", vmName);
+        }
+
+        try {
+            // Pull System.bootLayer
+            final Field field = System.class.getDeclaredField("bootLayer");
+            field.setAccessible(true);
+            final ModuleLayer bootLayer = (ModuleLayer) field.get(null);
+            field.setAccessible(false);
+
+            // Invoke ModuleLayer::bindToLoader
+            final Method bindToLoader = ModuleLayer.class.getDeclaredMethod("bindToLoader", ClassLoader.class);
+            bindToLoader.setAccessible(true);
+            bindToLoader.invoke(bootLayer, classLoader);
+            bindToLoader.setAccessible(false);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
     }
 
     @Override