用getResourceAsStream替换FileInputStream

Question

I am currently reading in a public key file using the following code:

    // Read Public Key.
    File filePublicKey = new File(path + "/public.key");
    FileInputStream fis = new FileInputStream(path + "/public.key");
    byte[] encodedPublicKey = new byte[(int) filePublicKey.length()];
    fis.read(encodedPublicKey);
    fis.close();

However, I wish to include the key files in with my jar. I have dragged the key files into my project in eclipse and I am trying to load the public key using the following to replace what is above:

    InputStream is = getClass().getResourceAsStream( "/RSAAlgorithm2/public.key" );
    byte[] encodedPublicKey = new byte[(int) 2375];
    is.read(encodedPublicKey);
    is.close();

However I keep getting a NullPointerException.

java.lang.NullPointerException at RSA.LoadKeyPair(RSA.java:122) at RSA.main(RSA.java:31)

Is this because I am incorrectly loading in the file? Can files be dragged into eclipse and loaded like this or is it a requirement to have them seperate from the JAR?

Answer 1

Check if is is null after doing getResourceAsStream . If it is, the resource has not been found. In this case check the path to the file, it is relative to your classpath. I don't know your project setup but I would try to simply use "/public.key" …

Answer 2

With this name, you have to put the "public.key" file in the RSAAlgorithm2 package. That means in your "jar" file, you should see an entry named "RSAAlgorithm2/public.key".