如何在Java中生成特定范围内的随机整数? 在Java中覆盖equals和hashCode时应该考虑哪些问题? 如何使用Servlets和Ajax? 如何在Java中生成特定范围内的随机整数? 在Java 1.7或更高版本中,执行此操作的标准方法如下: import java.util.concurrent.ThreadLocalRandom; // nextInt is normally exclusive of the top value, // so add 1 to make it inclusive int randomNum = ThreadLocalRandom.current().nextInt(min, max + 1); 在Java 1.7之前,执行此操作的标准方法如下: import java.util.Random; /** * Returns a pseudo-random number between min and max, inclusive. * The difference between min and max can be at most * <code>Integer.MAX_VALUE - 1</code>. * * @param min Minimum value * @param max Maximum value. Must be greater than min. * @return Integer between min and max, inclusive. * @see java.util.Random#nextInt(int) */ public static int randInt(int min, int max) { // NOTE: This will (intentionally) not run as written so that folks // copy-pasting have to think about how to initialize their // Random instance. Initialization of the Random instance is outside // the main scope of the question, but some decent options are to have // a field that is initialized once and then re-used as needed or to // use ThreadLocalRandom (if using at least Java 1.7). // // In particular, do NOT do 'Random rand = new Random()' here or you // will get not very good / not very random results. Random rand; // nextInt is normally exclusive of the top value, // so add 1 to make it inclusive int randomNum = rand.nextInt((max - min) + 1) + min; return randomNum; } 在Java中覆盖equals和hashCode时应该考虑哪些问题? 如何使用Servlets和Ajax?