The NodeList NodeList method has no error Nodelist.item (0). Gettextcontent ()

When importing other people's source code, encountered a problem:

Show Nodelist.item (0). Gettextcontent () requires a cast, but the cast is prompted after casting:

This is done online because there are two classes with the same package name and class name in the jar package in the imported jar and in the JDK. At this point, the first class is introduced in the preceding class with a jar package. So the introduced class is not the error caused by the class we want.

The specific solution is as follows: Project Right--->build path-to-Configure build path--and order and export move the jar package that you want to call to the opposite. Here I need to refer to the JDK, after moving as shown:

Finally, the problem is solved.