hide BlockHoundRuntime from public API

agent/src/main/java/reactor/blockhound/BlockHoundRuntime.java

@@ -22,15 +22,15 @@
 // Warning!!! This class MUST NOT be loaded by any classloader other than the bootstrap one.
 // Otherwise, non-bootstrap classes will be referring to it, but only the bootstrap one gets
 // initialized.
-public class BlockHoundRuntime {
+class BlockHoundRuntime {
 
     @SuppressWarnings("unused")
-    public static volatile Consumer<Object[]> blockingMethodConsumer;
+    static volatile Consumer<Object[]> blockingMethodConsumer;
 
     @SuppressWarnings("unused")
-    public static volatile Predicate<Thread> threadPredicate;
+    static volatile Predicate<Thread> threadPredicate;
 
-    public static final ThreadLocal<Boolean> IS_ALLOWED = ThreadLocal.withInitial(() -> {
+    static final ThreadLocal<Boolean> IS_ALLOWED = ThreadLocal.withInitial(() -> {
         if (threadPredicate.test(Thread.currentThread())) {
             return false;
         }
@@ -41,7 +41,7 @@ public class BlockHoundRuntime {
     });
 
     @SuppressWarnings("unused")
-    public static void checkBlocking(String internalClassName, String methodName, int modifiers) {
+    static void checkBlocking(String internalClassName, String methodName, int modifiers) {
         if (Boolean.FALSE == IS_ALLOWED.get()) {
             blockingMethodConsumer.accept(new Object[] {
                     internalClassName.replace("/", "."),

agent/src/main/java/reactor/blockhound/InstrumentationUtils.java

@@ -16,6 +16,13 @@
 
 package reactor.blockhound;
 
+import net.bytebuddy.jar.asm.ClassReader;
+import net.bytebuddy.jar.asm.ClassVisitor;
+import net.bytebuddy.jar.asm.ClassWriter;
+import net.bytebuddy.jar.asm.FieldVisitor;
+import net.bytebuddy.jar.asm.MethodVisitor;
+import net.bytebuddy.jar.asm.Opcodes;
+
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -35,19 +42,59 @@ static void injectBootstrapClasses(Instrumentation instrumentation, String... cl
         try (ZipOutputStream zipOutputStream = new ZipOutputStream(new FileOutputStream(tempJarFile))) {
             for (String className : classNames) {
                 String classFile = className.replace(".", "/") + ".class";
-                InputStream inputStream = classLoader.getResourceAsStream(classFile);
-                ZipEntry e = new ZipEntry(classFile);
-                zipOutputStream.putNextEntry(e);
-
-                byte[] buf = new byte[4096];
-                int n;
-                while ((n = inputStream.read(buf)) > 0) {
-                    zipOutputStream.write(buf, 0, n);
+                try (InputStream inputStream = classLoader.getResourceAsStream(classFile)) {
+                    ZipEntry entry = new ZipEntry(classFile);
+                    zipOutputStream.putNextEntry(entry);
+
+                    ClassReader cr = new ClassReader(inputStream);
+                    ClassWriter cw = new ClassWriter(cr, 0);
+
+                    cr.accept(new MakePublicClassVisitor(cw), 0);
+
+                    zipOutputStream.write(cw.toByteArray());
                 }
 
                 zipOutputStream.closeEntry();
             }
         }
         instrumentation.appendToBootstrapClassLoaderSearch(new JarFile(tempJarFile));
     }
+
+    /**
+     * Makes the class, fields and methods public
+     */
+    static class MakePublicClassVisitor extends ClassVisitor {
+
+        MakePublicClassVisitor(ClassWriter cw) {
+            super(Opcodes.ASM7, cw);
+        }
+
+        @Override
+        public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+            super.visit(version, access | Opcodes.ACC_PUBLIC, name, signature, superName, interfaces);
+        }
+
+        @Override
+        public FieldVisitor visitField(int access, String name, String descriptor, String signature, Object value) {
+            switch (name) {
+                case "blockingMethodConsumer":
+                case "threadPredicate":
+                case "IS_ALLOWED":
+                    access = access | Opcodes.ACC_PUBLIC;
+                    break;
+            }
+            return super.visitField(access, name, descriptor, signature, value);
+        }
+
+        @Override
+        public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
+            switch (name) {
+                case "checkBlocking":
+                    access = access | Opcodes.ACC_PUBLIC;
+                    break;
+            }
+
+            return super.visitMethod(access, name, descriptor, signature, exceptions);
+        }
+    }
 }