main--

public override System.Collections.Generic.IEnumerable<FigurePosition> GetPossibleTargets(BoardState state)
{
    for (FigurePosition pos = Position; pos.IsValid() && !state.IsPositionOccupied(pos, false); pos += new Vector(1, 1))
        yield return pos;
    for (FigurePosition pos = Position; pos.IsValid() && !state.IsPositionOccupied(pos, false); pos += new Vector(-1, 1))
        yield return pos;
    for (FigurePosition pos = Position; pos.IsValid() && !state.IsPositionOccupied(pos, false); pos += new Vector(1, -1))
        yield return pos;
    for (FigurePosition pos = Position; pos.IsValid() && !state.IsPositionOccupied(pos, false); pos += new Vector(-1, -1))
        yield return pos;

main--

package me.main__.nanotech.dirty;

import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtMethod;
import me.main__.nanotech.NanoTech;
import org.bukkit.Bukkit;

import java.lang.reflect.Array;
import java.lang.reflect.Constructor;

main--

package com.onarandombox.mvapi;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

public final class EMF {
    private static final EntityManagerFactory emfInstance =
        Persistence.createEntityManagerFactory("transactions-optional");

    private EMF() {}

main--

Before the change

Bukkit plugin

• accesses only the bukkit API
• doesn't care about the implementation/doesn't touch it
• limited possibilities because things like packet manipulation can't go into Bukkit
• (almost) fully downwards compatible