理解:”移除双重否定”是指把代码中的双重否定语句修改成简单的肯定语句,这样即让代码可读,同时也给维护带来了方便. 详解:避免双重否定重构本身非常容易实现,但我们却在太多的代码中见过因为双重否定降低了代码的可读性以致于非常让人容易误解真正意图.存在双重否定的代码具有非常大的危害性,因为这种类型的代码容易引起错误的假设,错误的假设又会导致书写出错误的维护代码,最终会导致bug产生.具体可以看下面的代码: public class Order { public void Checkout(IEnume…
理解:移除重复的代码,顾名思义就是把多处重复的代码搬移到一个公共的地方,来减少代码量,提高代码可维护性. 详解:看下面的例子就很容易理解 重构前code using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; namespace ReflectorDemo { public class MedicalRecord { public…
Given an array nums and a value val, remove all instances of that value in-place and return the new length. Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory. The order of ele…
Given several boxes with different colors represented by different positive numbers. You may experience several rounds to remove boxes until there is no box left. Each time you can choose some continuous boxes with the same color (composed of k boxes…
尽管我在很多代码中发现了这种严重降低可读性并往往传达错误意图的坏味道,但这种重构本身还是很容易实现的.这种毁灭性的代码所基于的假设导致了错误的代码编写习惯,并最终导致bug.如下例所示: public class Order { public void Checkout(List<Product> products, Customer customer) { if (!customer.getNotFlagged()) { // the customer account is flagged…
公众号:爱写bug 给定一个数组 nums 和一个值 val,你需要原地移除所有数值等于 val 的元素,返回移除后数组的新长度. 不要使用额外的数组空间,你必须在原地修改输入数组并在使用 O(1) 额外空间的条件下完成. 元素的顺序可以改变.你不需要考虑数组中超出新长度后面的元素. Given an array nums and a value val, remove all instances of that value in-place and return the new length.…
2009年,Sean Chambers在其博客中发表了31 Days of Refactoring: Useful refactoring techniques you have to know系列文章,每天发布一篇,介绍一种重构手段,连续发文31篇,故得名“重构三十一天:你应该掌握的重构手段”.此外,Sean Chambers还将这31篇文章[即31种重构手段]整理成一本电子书, 以下是博客原文链接和电子书下载地址: 博客原文:http://lostechies.com/seanchamber…
Make changes on existing code for subsequent and constant changes of requirement. Reference:http://www.refactoring.com/catalog/index.html Ways of Refactorings Add Parameter Change Bidirectional Association to Unidirectional Change Reference to Value…
1 public class CollectionTest { 2 3 @Test 4 public void test3(){ 5 HashSet set = new HashSet(); 6 Person p1 = new Person(1001,"AA"); 7 Person p2 = new Person(1002,"BB"); 8 9 set.add(p1); 10 set.add(p2); 11 System.out.println(set); 12 /…
