Searching an ArrayList for a matching parameter

Question

I have two classes Museum and Painting. Painting class is working as expected, but I am having issues with the Museum class. The purpose of the method is to return an ArrayList of paintings the museum has, which matches the parameter string.

When I try to compile the code, I am getting lots of error messages and clearly I am not compiling the code correctly.

For example, if there is a Painting by Picasso - it should just return all those paintings and nothing else.

I think I may have missed a step - potentially by creating a local variable to store it in first, but I'm at a bit of a brick wall. I also wonder if String is correct when the ArrayList uses the Painting object.

Does anyone know what I'm missing here?

public class Museum  {
    //creating the fields
    private ArrayList<Painting> paintings;
    private String name;

    /**
     * Create a Museum Class 
     */
    public Museum(String aMuseum) {
        paintings = new ArrayList<>();
        name = aMuseum;
    }

    public String listMatches(String searchString)
    {
        if(filename.equals(searchString)) {
            return filename;
        }
    }
}

Answer 1

Searching paintings by artist should return a sublist of paintings (it may be empty if no painting is found):

public List<Painting> listMatches(String artist) {
    List<Painting> matches = new ArrayList<>();
    for (Painting painting : paintings) {
        if (artist.equals(painting.getArtist())) {
            matches.add(painting);
        }
    }

    return matches;
}

---

Stream API may be used for this (more concise and functional style):

public List<Painting> listMatches(String artist) {
    return paintings.stream()
        .filter(p -> artist.equals(p.getArtist()))
        .collect(Collectors.toList());
}