if sentence error. compare string NullPointerException [duplicate]

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• What is a Null Pointer Exception, and how do I fix it? 12 answers

i´m trying to compare 2 String, if string are equals, a warning appears. But if the string aren´t equals insert data into a database but a error message appears:

The code is this:

I don't understand, if i quit the line 274 the code run. Please help!!! Thank You