patternjavaMinor

Get object in a Set that is an instance of a generically specified type

Submitted by: @import:stackexchange-codereview·Mar 10, 2026·

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genericallytypeinstancegetthatobjectsetspecified

Problem

Are there ways to simplify the getLoadComponent(Class type) method? The call LoadComponentFX lcfx = l.getLoadComponent(LoadComponentFX.class); seams a bit clumsy to me.

Here is my code:

public abstract class LoadComponent {}

public class LoadComponentFX extends LoadComponent {}

public class Load {
    Set lc;

    public  T getLoadComponent(Class type) {
        for (final LoadComponent l : lc) {
            if (type.isInstance(l)) {
                return (T) l;
            }
        }
        return null;
    }
}

Test code:

public class LoadTest {
    public static void main(final String[] args) {
        Load l = new PointLoad();

        LoadComponentFX lcfx = l.getLoadComponent(LoadComponentFX.class);
    }
}

Solution

As your current code now indirectly forces the set to only contain one of each component, then you could use a Map instead. This would also reduce the need for the loop

public class Load {
    Map, LoadComponent> lc;

    public  T getLoadComponent(Class type) {
        return (T) lc.get(type);
    }
}

Other comments:

Make sure the Map is set to private final

lc is not a good name. There's really no need to save bytes by shortening variable names. A better name would be loadComponents

When adding items to the map, you can use loadComponents.put(obj.getClass(), obj);

Code Snippets

public class Load {
    Map<Class<? extends LoadComponent>, LoadComponent> lc;

    public <T extends LoadComponent> T getLoadComponent(Class<T> type) {
        return (T) lc.get(type);
    }
}

Context

StackExchange Code Review Q#61546, answer score: 4

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