在Eclipse / Java中重构:应用"提取方法" (Alt + Shift + M)之后

时间:2014-06-29 11:06:41

标签: java eclipse refactoring

我想知道是否可以通过调用之前提取的方法来替换某些代码。

例如,我有一个类似模式的类:

public class ExtractMethodDemo {
    public void doSequence() {
        long n1; n2;
        // Compute and print count
        n1 = 70;
        n2 = compute(n1);                                        // <-- 1st
        System.out.printf("Input %4s, output = %s.%n", n1, n2);  // <-- occurrence
        ....
        // Compute and print count again
        n2 = n2 % 100;
        n1 = compute(n2);                                        // <-- Nth
        System.out.printf("Input %4s, output = %s.%n", n2, n1);  // <-- occurrence
    }
}

refactor using a method但由于某些原因,某些事件仍然没有重构(如果取消选中Replace additional occurrences...,或者稍后粘贴了相同的代码,则可能):

public void doSequence() {
    long n1; n2;
    // Compute and print count
    n1 = 70;
    n2 = doAll(n1);                                          // <--- method extracted
    // ....
    // Compute and print count again
    n2 = n2 % 100;
    n1 = compute(n2);                                        // <--- oops! this one is
    System.out.printf("Input %4s, output = %s.%n", n2, n1);  // <--- still old style
}

private long doAll(long n) {
    long n2; // (BTW: not the n2 declared in doSequence!)
    n2 = compute(n);
    System.out.printf("Input %4s, output = %s.%n", n, n2);
    return n2;
}

之后是否可以重构重新定序序列:

public void doSequence() {
    long n1; n2;
    // Compute and print count
    n1 = 70;
    n2 = doAll(n1);
    // ....
    // Compute and print count again
    n2 = n2 % 100;
    n1 = doAll(n2);    // <--- would be great to apply same refactoring afterwards
}

1 个答案:

答案 0 :(得分:1)

可能比重新编写代码更好一点就是在新代码的整个主体上提取方法,并检查Replace Additional Occurrences,然后从原始调用内联新方法。这样,您选择错误行的风险就会降低。

更新:以下是一个例子:

你从

开始
extractableCode(1);
extractableCode(2);
extractableCode(3);

并提取原始块,留下

extractedMethod(1);
extractableCode(2);
extractableCode(3);
...
function extractedMethod(int i) {
    extractableCode(i);
}

您的方法是内联extractMethod,然后使用Replace All Occurrences重复提取。我建议你从extractedMethod()内部提取:

extractedMethod(1);
secondExtractedMethod(2);
secondExtractedMethod(3);
...
function extractedMethod(int i) {
    secondExtractedMethod(i);
}
function secondExtractedMethod(int i) {
    extractableCode(i);
}

然后将原始调用内联到第一个提取的方法:

secondExtractedMethod(1);
secondExtractedMethod(2);
secondExtractedMethod(3);
...
function secondExtractedMethod(int i) {
    extractableCode(i);
}

然后,可能重命名第二个提取的方法。它与您最初的建议略有不同,但它可能更可靠。