CrimeLab.java

package ru.orlovph.criminalintent2020;

import android.content.Context;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

//  Singleton class - a class that allows only one
//  instance of itself to be created
public class CrimeLab {
    private static CrimeLab sCrimeLab;

    private List<Crime> mCrimes;

    public static CrimeLab get(Context context) {
        if (sCrimeLab == null) {
            sCrimeLab = new CrimeLab(context);
        }
        return sCrimeLab;
    }

    private CrimeLab(Context context) {
        mCrimes = new ArrayList<>();
    }

    public void addCrime(Crime crime){
        mCrimes.add(crime);
    }

    public List<Crime> getCrimes(){
        return mCrimes;
    }

    public Crime getCrime(UUID id){
        for(Crime crime: mCrimes){
            if (crime.getId().equals(id)){
                return crime;
            }
        }
        return null;
    }

}