minecraft-source/src/com/mojang/realmsclient/KeyCombo.java

package com.mojang.realmsclient;

import java.util.Arrays;

public class KeyCombo {
    private final char[] chars;
    private int matchIndex;
    private final Runnable onCompletion;
    
    public KeyCombo(final char[] arr, final Runnable runnable) {
        this.onCompletion = runnable;
        if (arr.length < 1) {
            throw new IllegalArgumentException("Must have at least one char");
        }
        this.chars = arr;
    }
    
    public boolean keyPressed(final char character) {
        if (character == this.chars[this.matchIndex++]) {
            if (this.matchIndex == this.chars.length) {
                this.reset();
                this.onCompletion.run();
                return true;
            }
        }
        else {
            this.reset();
        }
        return false;
    }
    
    public void reset() {
        this.matchIndex = 0;
    }
    
    @Override
    public String toString() {
        return "KeyCombo{chars=" + Arrays.toString(this.chars) + ", matchIndex=" + this.matchIndex + '}';
    }
}