打印空值，但不抛出异常

public class NullPrintingExample {
    public static void main(String[] args) {
        String str = null;
        
        // 显式检查空值
        if (str == null) {
            System.out.println("The string is null.");
        } else {
            System.out.println("The string is: " + str);
        }
        
        // 默认值处理
        String defaultStr = (str != null) ? str : "Default Value";
        System.out.println("The string is: " + defaultStr);
        
        // 异常捕获
        try {
            System.out.println(str.length());
        } catch (NullPointerException e) {
            System.out.println("Caught NullPointerException: " + e.getMessage());
        }
    }
}