Resource loading using ClassLoader

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I have a resource file I need to load at runtime...it is in src/main/resources

I have successfully loaded the file to an inputStream using :

LoadSAC.class.getClassLoader().getResourceAsStream("someFile.txt");

LoadSAC is the class name ...

However, PMD complains about this suggests I use 

Thread.currentThread().getContextClassLoader().getResource(...)

I have tried numerous combinations and can never get the file to be located... Any thoughts... I have trolled a number of searches with plenty of suggestions but none seem to work...

Any thoughts ?

classloader java
1 Answers

If someFile.txt is in the same folder than LoadSAC.java, you can do:

InputStream is = LoadSAC.class.getResourceAsStream("someFile.txt");

If someFile.txt is in a subfolder subdir, you can do:

InputStream is = LoadSAC.class.getResourceAsStream("subdir/someFile.txt");

If your method in LoadSAC.java is non-static, you can replace LoadSAC.class.getResourceAsStream... by getClass().getResourceAsStream...

Be careful when compiling with ant or maven, by default, only .java file are copied as .class files in the build directory.

You have to write some rules to include someFile.txt in the final jar.

In your resource directory, you can add a little helper class like this:

import java.io.InputStream;
import java.net.URL;

import javax.activation.DataSource;
import javax.activation.URLDataSource;

public abstract class ResourceHelper {

    public static URL getURL(String name) {
        return ResourceHelper.class.getResource(name);
    }

    public static InputStream getInputStream(String name) {
        return ResourceHelper.class.getResourceAsStream(name);
    }

    public static DataSource getDataSource(String name) {
        return new URLDataSource(getURL(name));
    }
}

In LoadSAC.java just call:

InputStream is = ResourceHelper.getInputStream("someFile.txt");
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