Object[] args = pjp.getArgs(); // 3、校验每个参数 for (int i = 0; i < parameters.length; i++) { Parameter parameter = parameters[i]; // 3.1、获取参数注解 CheckNull annotation = parameter.getAnnotation(CheckNull.class); // 3.1、不存在@NotNull,忽略 if (Objects.isNull(annotation)) ...
importjava.util.Optional;Optional<Object>optional=Optional.ofNullable(object);if(optional.isPresent()){// 对象不为空时执行的代码}else{// 对象为空时执行的代码} 1. 2. 3. 4. 5. 6. 7. 8. 9. 4. 使用Objects类判断 Java 7引入了Objects类,提供了一些静态方法来处理对象的操作。其中的isNull()...
TheIntegerclass, which is a wrapper class for theintprimitive type, can be used to check if the value isnull. Understanding whether anIntegerobject isnullbecomes important in scenarios where the presence or absence of a value needs to be determined before performing operations on it. ...
isEmpty())) return false; //内层循环,负责worker数量+1 for (;;) { int wc = workerCountOf(c); //worker数量 //如果worker数量>线程池最大上限CAPACITY(即使用int低29位可以容纳的最大值) //或者( worker数量>corePoolSize 或 worker数量>maximumPoolSize ),即已经超过了给定的边界 if (wc >= ...
* @return 是否为数组对象,如果为{@code null} 返回false */publicstaticbooleanisArray(Object obj){if(null==obj){// throw new NullPointerException("Object check for isArray is null");returnfalse;}// 反射 获得类型returnobj.getClass().isArray();}...
StpUtil.checkLogin();return""; }/** * 当前会话注销登录 * *@return*/@GetMapping("logout")publicStringlogout(){ StpUtil.logout();return"已注销"; }/** * 获取当前会话账号id, 如果未登录,则抛出异常:`NotLoginException` * *@return*/@GetMapping("getLoginId")publicStringgetLoginId(){Objectlo...
for (int i = 0; i < 5; i++) { System.out.println("Count is: " + i); } } } 解释 int i = 0:初始化循环计数器 i 为 0。 i < 5:循环条件,只要 i 小于 5,循环就会继续。 i++:在每次循环迭代结束时将 i 的值增加 1。
[Object Copy (ms): Min: 4.9, Avg: 5.1, Max: 5.2, Diff: 0.3, Sum: 20.4] [Termination (ms): Min: 0.0, Avg: 0.0, Max: 0.0, Diff: 0.0, Sum: 0.0] [GC Worker Other (ms): Min: 0.0, Avg: 0.4, Max: 1.3, Diff: 1.3, Sum: 1.4] [GC Worker Total (ms): Min: 6.4, Avg: ...
小结: 1、 This method is used to replace the definition of a class without reference to the existing class file bytes, as one might do when recompiling f
publicElement(int atomicNumber, Color color){ if(color ==null) thrownewIllegalArgumentException("color is null"); this.atomicNumber= atomicNumber; this.color= color; } // rest of the code } 类Element的构造函数未检查atomicNumber是否在 1-118 范围内(所有已知元素的原子序数在 1 到 118 之间)...