NullPointerException 空指针异常
- 继承结构:
- 代码:
/** * * Thrown when an application attempts to use {@code null} in a * case where an object is required. These include: * <ul> * <li>Calling the instance method of a {@code null} object. * <li>Accessing or modifying the field of a {@code null} object. * <li>Taking the length of {@code null} as if it were an array. * <li>Accessing or modifying the slots of {@code null} as if it * were an array. * <li>Throwing {@code null} as if it were a {@code Throwable} * value. * </ul> * <p> * Applications should throw instances of this class to indicate * other illegal uses of the {@code null} object. * * {@code NullPointerException} objects may be constructed by the * virtual machine as if {@linkplain Throwable#Throwable(String, * Throwable, boolean, boolean) suppression were disabled and/or the * stack trace was not writable}. * * @author unascribed * @since JDK1.0 */ public class NullPointerException extends RuntimeException { private static final long serialVersionUID = 5162710183389028792L; /** * Constructs a {@code NullPointerException} with no detail message. */ public NullPointerException() { super(); } /** * Constructs a {@code NullPointerException} with the specified * detail message. * * @param s the detail message. */ public NullPointerException(String s) { super(s); } }
IllegalArgumentException 参数不合法异常
UnsupportedOperationException 功能不支持异常
IndexOutOfBoundsException 数组下标越界异常
OutOfMemoryError 内存溢出异常
ClassCastException 类型转换异常