java.lang.VerifyError: Bad type on operand stack

Exception in thread "main" java.lang.VerifyError: Bad type on operand stack 出现这个错误，如何更改

Exception in thread "main" java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    org/apache/poi/hwpf/HWPFDocument.write(Ljava/io/File;)V @8: invokespecial
  Reason:
    Type 'org/apache/poi/poifs/filesystem/POIFSFileSystem' (current frame, stack[1]) is not assignable to 'org/apache/poi/poifs/filesystem/NPOIFSFileSystem'
  Current Frame:
    bci: @8
    flags: { }
    locals: { 'org/apache/poi/hwpf/HWPFDocument', 'java/io/File', 'org/apache/poi/poifs/filesystem/POIFSFileSystem' }
    stack: { 'org/apache/poi/hwpf/HWPFDocument', 'org/apache/poi/poifs/filesystem/POIFSFileSystem', integer }
  Bytecode:
    0x0000000: 2bb8 00a9 4d2a 2c04 b700 a72c b600 a8b1
    0x0000010:                                        

    at com.primeton.knowledge.word.zhword.appWord(zhword.java:68)
    at com.primeton.knowledge.word.zhword.main(zhword.java:51)

代码有吗？？
错误表示 Java 编译器检测到字节码文件中存在非法的类型转换或非法的方法调用

你是不是单独修改某个类后然后单独编译了