Fileinputstream NullPointerException Java

Question

I searched for this error on StackOverflow but any topic seens to solve my problem. I have this code that opens a .txt file and inicialize objects variables and this error appears.

public void lerDoArquivo() {
    try {
        FileReader ler = new FileReader("Menu_de_itens.txt");
        BufferedReader reader = new BufferedReader(ler);
        String linha;

        while ((linha = reader.readLine()) != null) {
            processaEntrada(linha);
        }

        reader.close();
    } 
    catch (IOException e) {
        e.printStackTrace();
    }  
}

This is my stracktrace:

Exception in thread "main" java.lang.NullPointerException
    at java.io.FileInputStream.<init>(FileInputStream.java:130)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)
    at java.io.FileReader.<init>(FileReader.java:58)
    at ItemMenuDAOTxt.lerDoArquivo(ItemMenuDAOTxt.java:22)
    at ItemMenuDAO.<init>(ItemMenuDAO.java:16)
    at ItemMenuDAOTxt.<init>(ItemMenuDAOTxt.java:14)
    at ControleDeMenu.<init>(ControleDeMenu.java:21)
    at FastFoodOO.main(FastFoodOO.java:11)

file not found. read about classpath during runtime and use `getClass().getResource` or `getClassLoader().getResource` or their stream variants — UninformedUser, Jun 11 '19 at 17:56
`new FileReader` would only throw `NullPointerException` if you pass in a `null` value. If it was because the file didn't exist, as others have suggested, you'd get `FileNotFoundException`. — Andreas, Jun 11 '19 at 17:56
I agree with @Andreas. Is there something you didn't post here? — black panda, Jun 11 '19 at 18:25
As already said, unless you pass in a null parameter value, you shouldn't get that exception. But, if you disagree, why not grab your handy IDE and have a look at line 130 of the source for class `FileInputStream`, to see what that line does, and why it causes NPE? Or, my oh my, step through the code with the IDE's built-in debugger and see for yourself what the values are and what's going on? — Andreas, Jun 11 '19 at 20:12

score 0 · Answer 1 · answered Jun 11 '19 at 17:55

0

confirm you can read the file, most likely the file is no found.

 assert new File("./resources/Menu_de_itens.txt").canRead();

answered Jun 11 '19 at 17:55

Jeryl Cook

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Fileinputstream NullPointerException Java

1 Answers1