检测类文件时出错 (asm.ClassWriter.getCommonSuperClass)

Question

在仪器上出现错误

java.lang.RuntimeException: java.lang.ClassNotFoundException: Deposit
    at org.objectweb.asm.ClassWriter.getCommonSuperClass(Unknown Source)
    at org.objectweb.asm.ClassWriter.a(Unknown Source)
    at org.objectweb.asm.Frame.a(Unknown Source)
    at org.objectweb.asm.Frame.a(Unknown Source)
    at org.objectweb.asm.MethodWriter.visitMaxs(Unknown Source)
    at com.jConSequence.instrumentor.methodProber.AdddataBaseDetailsInstructions$AdddataBaseDetailsMethodInstructions.visitMaxs(AdddataBaseDetailsInstructions.java:131)
    at org.objectweb.asm.ClassReader.accept(Unknown Source)
    at org.objectweb.asm.ClassReader.accept(Unknown Source)
    at com.jConSequence.instrumentor.PrintLoadedClasses.print(PrintLoadedClasses.java:31)
    at com.jConSequence.tooGUI.RevEnggToolGUI.jButton1ActionPerformed(RevEnggToolGUI.java:487)
    at com.jConSequence.tooGUI.RevEnggToolGUI.access$0(RevEnggToolGUI.java:471)
    at com.jConSequence.tooGUI.RevEnggToolGUI$1.actionPerformed(RevEnggToolGUI.java:127)
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
    at java.awt.Component.processMouseEvent(Unknown Source)
    at javax.swing.JComponent.processMouseEvent(Unknown Source)
    at java.awt.Component.processEvent(Unknown Source)
    at java.awt.Container.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$000(Unknown Source)
    at java.awt.EventQueue$1.run(Unknown Source)
    at java.awt.EventQueue$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$2.run(Unknown Source)
    at java.awt.EventQueue$2.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

在检测课程时

D:\workspaces\workspace\bankManagement\bin\Account.class
D:\workspaces\workspace\bankManagement\bin\ATM.class
D:\workspaces\workspace\bankManagement\bin\ATMCaseStudy.class
D:\workspaces\workspace\bankManagement\bin\BalanceInquiry.class
D:\workspaces\workspace\bankManagement\bin\BankDatabase.class
D:\workspaces\workspace\bankManagement\bin\CashDispenser.class
D:\workspaces\workspace\bankManagement\bin\Deposit.class
D:\workspaces\workspace\bankManagement\bin\DepositSlot.class
D:\workspaces\workspace\bankManagement\bin\Keypad.class
D:\workspaces\workspace\bankManagement\bin\Screen.class
D:\workspaces\workspace\bankManagement\bin\Transaction.class

我正在使用 apache commonsIO 将上面的一组类作为字节流读取。

然后使用 asm 库检测它们。

最后它们被转换成类文件。

正是在这一点上，我收到了这个错误任何人都可以解释原因和可能的解决方案。

Answer 1

发生此错误是因为 ASM 正在生成堆栈映射帧，并且对于某些字节码，堆栈映射帧必须包含两个类的公共超类。 默认情况下，ASM通过 Class.forName加载类来实现这一点，然后使用反射实现适当的算法。 据推测，ASM 库无法从其类加载器加载您的 Deposit 类。

为避免该错误，您需要使用 SKIP_FRAMES（注意：Java 7 使用的类文件版本 51.0 需要堆栈映射帧，因此如果您生成 Java 7 字节码，这是不可选择的），或者您需要继承 ClassWriter 并覆盖 getCommonSuperClass。 根据您的代码在做什么，也许您可以使用字符串比较对答案进行硬编码，或者您可以采用 ASM 实现并重写它以使用您指定的 ClassLoader。

Answer 2

我也遇到了这个问题。 在尝试编写自己的 ClassWriter 并在 Internet 上搜索之后，我终于找到了一个非常适合我的实现： SafeClassWriter.java

希望它会有所帮助。