コード例 #1
0
  @Override
  public boolean transform(
      ClassLoader loader,
      String className,
      Class<?> classBeingRedefined,
      ProtectionDomain protectionDomain,
      ClassFile file)
      throws IllegalClassFormatException, BadBytecode {

    /**
     * Hack up the proxy factory so it stores the proxy ClassFile. We need this to regenerate
     * proxies.
     */
    if (file.getName().equals("org.jboss.weld.bean.proxy.ProxyFactory")) {
      for (final MethodInfo method : (List<MethodInfo>) file.getMethods()) {
        if (method.getName().equals("createProxyClass")) {
          final MethodInvokationManipulator methodInvokationManipulator =
              new MethodInvokationManipulator();
          methodInvokationManipulator.replaceVirtualMethodInvokationWithStatic(
              ClassLoader.class.getName(),
              WeldProxyClassLoadingDelegate.class.getName(),
              "loadClass",
              "(Ljava/lang/String;)Ljava/lang/Class;",
              "(Ljava/lang/ClassLoader;Ljava/lang/String;)Ljava/lang/Class;",
              loader);
          methodInvokationManipulator.replaceVirtualMethodInvokationWithStatic(
              "org.jboss.weld.util.bytecode.ClassFileUtils",
              WeldProxyClassLoadingDelegate.class.getName(),
              "toClass",
              "(Ljavassist/bytecode/ClassFile;Ljava/lang/ClassLoader;Ljava/security/ProtectionDomain;)Ljava/lang/Class;",
              "(Ljavassist/bytecode/ClassFile;Ljava/lang/ClassLoader;Ljava/security/ProtectionDomain;)Ljava/lang/Class;",
              loader);
          HashSet<MethodInfo> modifiedMethods = new HashSet<MethodInfo>();
          methodInvokationManipulator.transformClass(file, loader, true, modifiedMethods);
          for (MethodInfo m : modifiedMethods) {
            m.rebuildStackMap(ClassPool.getDefault());
          }
          return true;
        } else if (method.getName().equals("<init>")) {

          Integer beanArgument = null;
          int count = 0;
          for (final String paramType :
              DescriptorUtils.descriptorStringToParameterArray(method.getDescriptor())) {
            if (paramType.equals("javax/enterprise/inject/spi/Bean")) {
              beanArgument = count;
              break;
            } else if (paramType.equals("D") || paramType.equals("J")) {
              count += 2;
            } else {
              count++;
            }
          }
          if (beanArgument == null) {
            log.error(
                "Constructor org.jboss.weld.bean.proxy.ProxyFactory.<init>"
                    + method.getDescriptor()
                    + " does not have a bean parameter, proxies produced by this factory will not be reloadable");
            continue;
          }

          // similar to other tracked instances
          // but we need a strong ref
          Bytecode code = new Bytecode(file.getConstPool());
          code.addAload(0);
          code.addAload(beanArgument);
          code.addInvokestatic(
              WeldClassChangeAware.class.getName(),
              "addProxyFactory",
              "(Lorg/jboss/weld/bean/proxy/ProxyFactory;)V");
          CodeIterator it = method.getCodeAttribute().iterator();
          it.skipConstructor();
          it.insert(code.get());
        }
      }
    }
    return false;
  }
コード例 #2
0
  public boolean transformClass(ClassFile file, ClassLoader loader, boolean modifiableClass) {
    Set<Integer> methodCallLocations = new HashSet<Integer>();
    Integer newCallLocation = null;
    Integer methodReflectionLocation = null;
    Integer fakeCallRequiredLocation = null;
    // first we need to scan the constant pool looking for
    // CONSTANT_method_info_ref structures
    ConstPool pool = file.getConstPool();
    for (int i = 1; i < pool.getSize(); ++i) {
      // we have a method call
      if (pool.getTag(i) == ConstPool.CONST_Methodref) {
        String className = pool.getMethodrefClassName(i);
        String methodName = pool.getMethodrefName(i);

        if (className.equals(Method.class.getName())) {
          if (methodName.equals("invoke")) {
            // store the location in the const pool of the method ref
            methodCallLocations.add(i);
            // we have found a method call

            // if we have not already stored a reference to our new
            // method in the const pool
            if (newCallLocation == null) {
              methodReflectionLocation =
                  pool.addClassInfo("org.fakereplace.reflection.MethodReflection");
              int nt = pool.addNameAndTypeInfo("fakeCallRequired", "(Ljava/lang/reflect/Method;)Z");
              fakeCallRequiredLocation = pool.addMethodrefInfo(methodReflectionLocation, nt);
              newCallLocation = pool.addNameAndTypeInfo(METHOD_NAME, REPLACED_METHOD_DESCRIPTOR);
            }
          }
        }
      }
    }

    // this means we found an instance of the call, now we have to iterate
    // through the methods and replace instances of the call
    if (newCallLocation != null) {
      List<MethodInfo> methods = file.getMethods();
      for (MethodInfo m : methods) {
        try {
          // ignore abstract methods
          if (m.getCodeAttribute() == null) {
            continue;
          }
          CodeIterator it = m.getCodeAttribute().iterator();
          while (it.hasNext()) {
            // loop through the bytecode
            int index = it.next();
            int op = it.byteAt(index);
            // if the bytecode is a method invocation
            if (op == CodeIterator.INVOKEVIRTUAL) {
              int val = it.s16bitAt(index + 1);
              // if the method call is one of the methods we are
              // replacing
              if (methodCallLocations.contains(val)) {
                Bytecode b = new Bytecode(file.getConstPool());
                // our stack looks like Method, instance,params
                // we need Method, instance, params , Method
                b.add(Opcode.DUP_X2);
                b.add(Opcode.POP);
                b.add(Opcode.DUP_X2);
                b.add(Opcode.POP);
                b.add(Opcode.DUP_X2);
                b.addInvokestatic(
                    methodReflectionLocation, "fakeCallRequired", "(Ljava/lang/reflect/Method;)Z");
                b.add(Opcode.IFEQ);
                JumpMarker performRealCall = JumpUtils.addJumpInstruction(b);
                // now perform the fake call
                b.addInvokestatic(methodReflectionLocation, "invoke", REPLACED_METHOD_DESCRIPTOR);
                b.add(Opcode.GOTO);
                JumpMarker finish = JumpUtils.addJumpInstruction(b);
                performRealCall.mark();
                b.addInvokevirtual(Method.class.getName(), METHOD_NAME, METHOD_DESCRIPTOR);
                finish.mark();
                it.writeByte(CodeIterator.NOP, index);
                it.writeByte(CodeIterator.NOP, index + 1);
                it.writeByte(CodeIterator.NOP, index + 2);
                it.insert(b.get());
              }
            }
          }
          m.getCodeAttribute().computeMaxStack();
        } catch (Exception e) {
          log.error("Bad byte code transforming " + file.getName());
          e.printStackTrace();
        }
      }
      return true;
    } else {
      return false;
    }
  }