public class EzyActionFrame5Seconds extends EzyActionFrame {

    public EzyActionFrameSecond() {
        this(Integer.MAX_VALUE);
    }

    public EzyActionFrameSecond(long maxActions) {
        super(maxActions);
    }

    public EzyActionFrameSecond(long maxActions, long startTime) {
        super(maxActions, startTime);
    }

    @Override
    protected final int getExistsTime() {
        return 5000;
    }

    @Override
    public final EzyActionFrame nextFrame() {
        return new EzyActionFrame5Seconds(maxActions, endTime);
    }
}

You can take a look here and here to see how to use

1. Yes, it's correct
2. I don't understand what do exactly you mean about: 1/6, 2/7 but you can create many frame for many time frame that you want

Firstly, I will create an instance of EzyActionFrame3Seconds (start:0/end:0+3/capacity:4). A request comes (second 0.5), add to the frame. Next request comes (second 1), add to the frame. 3rd request comes (second 2), add to he frame. 4th request comes (second 3 == endTime), add to the frame. This point, the first frame will end its life without violate the rule.

5th request comes (second 4), create second EzyActionFrame3Seconds(start:3/end:3+3), add to this frame. 6th request comes (second 4.1), add to the frame. 7th request comes (second 4.2), add to the frame. 8th request comes (second 4.3), add to the frame.

The second frame does not break the rule, right?

But the rule actually are break! From second 2 to second 4.3, it take 4.3 - 2 = 2.3 seconds, within 3 seconds; and from second 2 to second 4.3, there are 5 requests (4,5,6,7,8) (>4).

Am I wrong?

if (frame.isInvalid()) it should be if (frame.isValid()), right?

But even so, the result is not my expectation.

This bellow code is my test case for the above example

package com.example.ratelimiting;

import lombok.Getter;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class EzyCompositeActionFrame {

    private final int seconds;
    private long totalActions;
    private final long maxActions;
    private final List<EzyActionFrame> inSecondFrames;

    public EzyCompositeActionFrame(int seconds, long maxActions) {
        this.seconds = seconds;
        this.maxActions = maxActions;
        this.inSecondFrames = new ArrayList<>();

    }

    public synchronized boolean addActions(int actions) {
        final long currentTime = System.currentTimeMillis();
        final long minStartTime = currentTime - seconds;
        final Iterator<EzyActionFrame> iterator = inSecondFrames.iterator();
        while (iterator.hasNext()) {
            final EzyActionFrame frame = iterator.next();
            if (frame.getStartTime() < minStartTime) {
                iterator.remove();
            } else {
                break;
            }
        }
        EzyActionFrame currentFrame = null;
        for (EzyActionFrame frame : inSecondFrames) {
            if (frame.isValid()) {
                currentFrame = frame;
                break;
            }
        }
        if (currentFrame == null) {
            currentFrame = new EzyActionFrameSecond(
                    maxActions,
                    currentTime
            );
            inSecondFrames.add(currentFrame);
        }
        currentFrame.addActions(actions);
        totalActions = inSecondFrames
                .stream()
                .mapToLong(EzyActionFrame::getActions)
                .sum();
        return totalActions > maxActions;
    }

    public synchronized boolean isInvalid() {
        return totalActions > maxActions;
    }

    @Override
    public String toString() {
        final long startTime = inSecondFrames.isEmpty()
                ? System.currentTimeMillis()
                : inSecondFrames.get(0).startTime;
        final long endTime = startTime + seconds;
        final SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss.SSS");
        return df.format(startTime) +
                " -> " +
                df.format(endTime) +
                ", actions: " + totalActions +
                ", maxActions: " + maxActions +
                ", tooManyRequest: " + isInvalid();
    }

    @Getter
    static abstract class EzyActionFrame {

        protected final long endTime;
        protected final long startTime;
        protected final long maxActions;
        protected volatile long actions;

        public EzyActionFrame(long maxActions) {
            this(maxActions, System.currentTimeMillis());
        }

        public EzyActionFrame(long maxActions, long startTime) {
            this.maxActions = maxActions;
            this.startTime = startTime;
            this.endTime = startTime + getExistsTime();
        }

        protected abstract int getExistsTime();

        public boolean addActions(long actions) {
            return (this.actions += actions) > maxActions;
        }

        public boolean isExpired() {
            return System.currentTimeMillis() > endTime;
        }

        public boolean isInvalid() {
            return actions > maxActions;
        }

        public boolean isValid() {
            return !isInvalid();
        }

        public abstract EzyActionFrame nextFrame();

        @Override
        public String toString() {
            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss.SSS");
            return getClass().getSimpleName() +
                    ": " +
                    df.format(startTime) +
                    " -> " +
                    df.format(endTime);
        }
    }

    static class EzyActionFrameSecond extends EzyActionFrame {

        public EzyActionFrameSecond() {
            this(Integer.MAX_VALUE);
        }

        public EzyActionFrameSecond(long maxActions) {
            super(maxActions);
        }

        public EzyActionFrameSecond(long maxActions, long startTime) {
            super(maxActions, startTime);
        }

        @Override
        protected final int getExistsTime() {
            return 1000;
        }

        @Override
        public final EzyActionFrame nextFrame() {
            return new EzyActionFrameSecond(maxActions, endTime);
        }
    }

    public static void main(String[] args) throws Exception {
        final EzyCompositeActionFrame frame = new EzyCompositeActionFrame(3, 4);
        // 1st request comes (second ~0.5)
        Thread.sleep(500);
        System.out.println("add 1st actions");
        frame.addActions(1);
        System.out.println(frame);

        // 2nd request comes (second ~1)
        Thread.sleep(450);
        System.out.println("add 2nd actions");
        frame.addActions(2);
        System.out.println(frame);

        // 3th request comes (second ~2)
        Thread.sleep(1000);
        System.out.println("add 3th actions");
        frame.addActions(3);
        System.out.println(frame);

        // 4th request comes (second ~3)
        Thread.sleep(1000);
        System.out.println("add 4th actions");
        frame.addActions(4);
        System.out.println(frame);

        // 5th request comes (second ~4)
        Thread.sleep(1000);
        System.out.println("add 5th actions");
        frame.addActions(5);
        System.out.println(frame);

        // 6th request comes (second ~4.1)
        Thread.sleep(100);
        System.out.println("add 6th actions");
        frame.addActions(6);
        System.out.println(frame);

        // 7th request comes (second ~4.2)
        Thread.sleep(100);
        System.out.println("add 7th actions");
        frame.addActions(7);
        System.out.println(frame);

        // 8th request comes (second ~4.3)
        Thread.sleep(100);
        System.out.println("add 8th actions");
        frame.addActions(8);
        System.out.println(frame);
    }
}

Result:

add 1st actions
2022-10-14 19-39-13.346 -> 2022-10-14 19-39-13.349, actions: 1, maxActions: 4, tooManyRequest: false
add 2nd actions
2022-10-14 19-39-13.914 -> 2022-10-14 19-39-13.917, actions: 2, maxActions: 4, tooManyRequest: false
add 3th actions
2022-10-14 19-39-14.927 -> 2022-10-14 19-39-14.930, actions: 3, maxActions: 4, tooManyRequest: false
add 4th actions
2022-10-14 19-39-15.940 -> 2022-10-14 19-39-15.943, actions: 4, maxActions: 4, tooManyRequest: false
add 5th actions
2022-10-14 19-39-16.953 -> 2022-10-14 19-39-16.956, actions: 5, maxActions: 4, tooManyRequest: true
add 6th actions
2022-10-14 19-39-17.063 -> 2022-10-14 19-39-17.066, actions: 6, maxActions: 4, tooManyRequest: true
add 7th actions
2022-10-14 19-39-17.172 -> 2022-10-14 19-39-17.175, actions: 7, maxActions: 4, tooManyRequest: true
add 8th actions
2022-10-14 19-39-17.280 -> 2022-10-14 19-39-17.283, actions: 8, maxActions: 4, tooManyRequest: true

Expected result:

add 1st actions
2022-10-14 19-39-13.346 -> 2022-10-14 19-39-13.349, actions: 1, maxActions: 4, tooManyRequest: false
add 2nd actions
2022-10-14 19-39-13.914 -> 2022-10-14 19-39-13.917, actions: 2, maxActions: 4, tooManyRequest: false
add 3th actions
2022-10-14 19-39-14.927 -> 2022-10-14 19-39-14.930, actions: 3, maxActions: 4, tooManyRequest: false
add 4th actions
2022-10-14 19-39-15.940 -> 2022-10-14 19-39-15.943, actions: 4, maxActions: 4, tooManyRequest: false
add 5th actions
2022-10-14 19-39-16.953 -> 2022-10-14 19-39-16.956, actions: 5, maxActions: 4, tooManyRequest: false
add 6th actions
2022-10-14 19-39-17.063 -> 2022-10-14 19-39-17.066, actions: 6, maxActions: 4, tooManyRequest: false
add 7th actions
2022-10-14 19-39-17.172 -> 2022-10-14 19-39-17.175, actions: 7, maxActions: 4, tooManyRequest: false
add 8th actions
2022-10-14 19-39-17.280 -> 2022-10-14 19-39-17.283, actions: 8, maxActions: 4, tooManyRequest: true