java - 尝试减少/优化 if/else block 以提高可读性

Question

我有以下代码块。基本上，它决定了棒球中一名球员是否获得了多个垒，以及根据某人是否在第一/第二/第三上垒而发生的情况。我用蛮力做到了这一点，但是有没有办法重写它以大幅减少行数？我一直没能想出一个好的方法来做到这一点。

    int runsScored = 0;
    switch (action) {
        case 0:
            break;
        case 1:
            if (third) {
                if (second) {
                    if (first) {
                        runsScored = 2;
                        second = false;
                    } else {
                        runsScored = 2;
                        first = true;
                        second = false;
                        third = false;
                    }
                } else {
                    if (first) {
                        runsScored = 1;
                        second = true;
                        third = false;
                    } else {
                        runsScored = 1;
                        first = true;
                        third = false;
                    }
                }
            } else {
                if (second) {
                    if (first) {
                        third = true;
                    } else {
                        first = true;
                    }
                } else {
                    if (first) {
                        second = true;
                    } else {
                        first = true;
                    }
                }
            }
            break;
        case 2:
            if (third) {
                if (second) {
                    if (first) {
                        runsScored = 2;
                        first = false;
                    } else {
                        runsScored = 2;
                        third = false;
                    }
                } else {
                    if (first) {
                        runsScored = 1;
                        second = true;
                    } else {
                        runsScored = 1;
                        second = true;
                        third = false;
                    }
                }
            } else {
                if (second) {
                    if (first) {
                        runsScored = 1;
                        third = true;
                        second = true;
                        first = false;
                    } else {
                        runsScored = 1;
                    }
                } else {
                    if (first) {
                        first = false;
                        second = true;
                        third = true;
                    } else {
                        second = true;
                    }
                }
            }
            break;
        case 3:
            if (third) {
                if (second) {
                    if (first) {
                        runsScored = 3;
                        first = false;
                        second = false;
                        third = true;
                    } else {
                        runsScored = 2;
                        second = false;
                    }
                } else {
                    if (first) {
                        runsScored = 2;
                        first = false;
                    } else {
                        runsScored = 1;
                    }
                }
            } else {
                if (second) {
                    if (first) {
                        runsScored = 2;
                        third = true;
                        second = false;
                        first = false;
                    } else {
                        runsScored = 1;
                        second = false;
                        third = true;
                    }
                } else {
                    if (first) {
                        runsScored = 1;
                        first = false;
                        second = false;
                        third = true;
                    } else {
                        third = true;
                    }
                }
            }
            break;
        case 4:
            if (third) {
                if (second) {
                    if (first) {
                        runsScored = 4;
                        first = false;
                        second = false;
                        third = false;
                    } else {
                        runsScored = 3;
                        second = false;
                        third = false;
                    }
                } else {
                    if (first) {
                        runsScored = 3;
                        first = false;
                        third = false;
                    } else {
                        runsScored = 2;
                        third = false;
                    }
                }
            } else {
                if (second) {
                    if (first) {
                        runsScored = 3;
                        third = false;
                        second = false;
                        first = false;
                    } else {
                        runsScored = 2;
                        second = false;
                        third = false;
                    }
                } else {
                    if (first) {
                        runsScored = 2;
                        first = false;
                        second = false;
                        third = false;
                    } else {
                        runsScored = 1;
                    }
                }
            }
            break;
        default:
            throw new AssertionError();
    }
    return runsScored;

Answer 1

好吧，我会用类来描述这一点并让它自行管理，但这是一个很好的第一步。

        if (third) {
            if (second) {
                if (first) {
                    runsScored = 2;
                    second = false;
                } else {
                    runsScored = 2;
                    first = true;
                    second = false;
                    third = false;
                }

        if (third) {
            if (second) {
                    runsScored = 2;
                    second = false;
                if (!first) {
                    first = true;
                    third = false;
                }

即在 else 的两侧分解出相同的代码。一旦你清除了一些灌木丛，一些更简单的东西可能就会变得可见。