kieran的专栏

Strng字符串的值比较。字符串的比较有值比较、对象比较。值比较主要比较两个字符串的字符序列，有equals()和compareTo()。equals()：字符序列相同结果则为true。compareTo()：基于unicode值逐个字符比较。返回首次出现的不同字符的差值，如M和m，M比m小32，返回-32。                            如果长度不同，且短

最新整理的面试题合集，包括Java、前端、web开发、HTTP、数据库、操作系统等，用markdown语法编辑。https://github.com/PoldiChen/questions

1. windows下安装maven配置及集成到myeclipse系统变量添加MAVEN_HOME，值是maven解压的目录。path变量添加maven的bin目录，%MAVEN_HOME%\bin验证，打开cmd窗口，命令mvn -version，打印出版本信息即为配置成功。settings.xml配置本地仓库的目录 <settings>节点下添加 <local...

StringBuffer和StringBuilder都继承自AbstractStringBuilder，而AbstractStringBuilder和String都实现了CharSequence接口。StringBuilder是非线程安全的，StringBuffer是线程安全的，很多方法都用synchronized修饰，所以效率较低。StringBuffer的append方法p

Vector的实现和ArrayList十分类似，不同的是Vector是线程安全的，很多方法都用synchronized修饰。还有一个不同点是Vector每次扩容都是增加1倍，而ArrayList则是增加50%。/** * Appends the specified element to the end of this Vector. * * @param e

/** * A constant holding the minimum value an {@code int} can * have, -231. */ public static final int MIN_VALUE = 0x80000000; // 最小值，-2的31次方 /** * A constant holding th

/** * Priority queue represented as a balanced binary heap: the two * children of queue[n] are queue[2*n+1] and queue[2*(n+1)]. The * priority queue is ordered by comparator, or by the

// Red-black mechanics private static final boolean RED = false; // 基于红黑树的数据结构 private static final boolean BLACK = true;插入元素/** * Associates the specified value with the speci

/** * The backing map. */ private transient NavigableMap m; // 引用了一个NavigableMap类型的变量，用来存储set的值 // Dummy value to associate with an Object in the backing Map private static fina

private transient HashMap map; // 维护了一个HashMap的变量 // Dummy value to associate with an Object in the backing Map private static final Object PRESENT = new Object(); // 虚设的值添加元素/**

添加元素/** * Associates the specified value with the specified key in this map. * If the map previously contained a mapping for the key, the old * value is replaced. * * @param

transient int size = 0; // 数组长度 /** * Pointer to first node. * Invariant: (first == null && last == null) || * (first.prev == null && first.item != null) */ tra

/** * Default initial capacity. */ private static final int DEFAULT_CAPACITY = 10; // 默认的容量，10 /** * Shared empty array instance used for empty instances. */ private s

/**     * Compares this string to the specified object.  The result is {@code     * true} if and only if the argument is not {@code null} and is a {@code     * String} object that represents the

1. int和Integer的区别？int是基础数据类型，Integer是类型，是int的包装类。装箱：把int包装成IntegerInteget a = 100;拆箱：把Integer类型的对象简化成int类型int a = new Integer(100);

地址http://139.159.193.165/前端ReactMaterial-UI（Google的一款React组件库，自称是世界上最受欢迎的React组件库。国内的蚂蚁金服的Ant Design也很不错）源码：https://github.com/PoldiChen/know-about-me后台：Spring BootMyBatisMySQL源码：https://git...