下面是一个示例应用,演示了如何使用if语句判断Boolean对象是否为null,并根据判断结果执行相应的操作。 AI检测代码解析 publicclassExample{publicstaticvoidmain(String[]args){Booleanb=null;if(b==null){System.out.println("Boolean对象为null");}elseif(b){System.out.println("Boolean对象的值为true");}else{...
1. 获取Boolean对象 首先,我们需要获取一个Boolean对象,可以通过以下代码来创建一个Boolean对象: BooleanmyBoolean=null;// 创建一个值为null的Boolean对象 1. 2. 判断是否为null 接下来,我们需要判断这个Boolean对象是否为null,可以通过以下代码来实现: if(myBoolean==null){System.out.println("Boolean对象为null"...
✓ 已被采纳 当你有一个 boolean 它可以是 true 或false。 Yet when you have a Boolean it can be either Boolean.TRUE , Boolean.FALSE or null as any other object. In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces th...
}//public boolean isStudent() {//return isStudent;//}///public void setStudent(boolean isStudent) {//this.isStudent = isStudent;//}} 测试类2:(和上面的一样) packagecom.chinalife.utils;importorg.junit.Test;importcom.chinalife.proposal.common.util.CheckObjectIsNullUtils;/*** Description:测...
The if-else approach is a straightforward method to check if a string is null or empty in Java. It involves using conditional statements to evaluate the string and perform appropriate actions based on the result. Here’s how the basic if-else approach works: Firstly, we check if the string...
Learn how to effectively check if a Java string is null, empty, and whitespace. Enhance code reliability and prevent errors. Master string validation in Java now!
boolean 是基本类型,Boolean 是包装类型 boolean 取值为true/false,Boolean 取值为true/false/null 作为属性时,boolean 默认值为 false,Boolean 默认值为 null 2、布尔产生的空指针 //创建一个Switch 类,定义两种布尔类型的属性publicclassSwitch{privateBoolean status;privateboolean isOn;//setters, getters, toString...
}else{// Perform an alternate action when myStr is nullSystem.out.println “Please pass a validstringasan argument” } } 使用三元运算符 //boolean expression ? value1 : value2;StringmyStr = (str ==null) ?"": str.substring(0,20);//If str’s reference is null, myStr will be empty...
* * @return {@code true} if there is a value present, otherwise {@code false} */ public boolean isPresent() { return value != null; } 通过注释可以知道:如果值为null返回false,不为null返回true。 实例如下: if (name.isPresent()) { System.out.println(name.get());//输出javaHuang } ...
if(a == null || a.isEmpty());当然还可以使用org.apache.commons.lang.StringUtils工具。StringUtils...