java.lang.NullPointerException at dao.booDAO.addbook(booDAO.
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java.lang.NullPointerException at dao.booDAO.addbook(booDAO.java:23) at org.apache.jsp.addbookok_js
![java.lang.NullPointerException at dao.booDAO.addbook(booDAO.](/uploads/image/z/17976852-36-2.jpg?t=java.lang.NullPointerException+at+dao.booDAO.addbook%28booDAO.)
你的booDAO对象为null
检查你的代码
检查你的代码
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