public enum color{} //相当于public final class color extends enum{} enum类无法通过new创建实例对象,实例只能在枚举类内定义,且实例名称一般使用纯大写。enum Festival{ SPRING,SUMMER, AUTUMN, WINTER; //上面四个实际上都是枚举类的实例 /*相当于: public final static Festival SPRING=new Festival(); ...
* @param source the source bean * @param target the target bean * @param editable the class (or interface) to restrict property setting to * @param ignoreProperties array of property names to ignore * @throws BeansException if the copying failed * @see BeanWrapper */ private static void co...
Java 7 之前仅能使用 int / char 等小类型的值作为选择因子;从 Java 7 开始,可以在 switch 条件判断语句中使用 String 对象。 截止目前可用选择因子:char、byte、short、int、Character、Byte、Short、Integer、String 或枚举对象 enum AI检测代码解析 String s = "a"; switch (s) { case "a": System.out...
switch 不支持 long,是因为 switch 的设计初衷是对那些只有少数的几个值进行等值判断,如果值过于复杂,那么还是用 if 比较合适。 longx =111;switch(x) {//Incompatible types. Found: 'long', required: 'char, byte, short, int,Character, Byte, Short, Integer, String, or an enum'case111: System.ou...
Here we define four constants of theenum. The constants are given specific values. private int value; private Season(int value) { this.value = value; } When we define the constants, we also have to create a constructor. Constructors will be covered later in the tutorial. ...
Enum This is the common base class of all Java language enumeration classes. EnumConstantNotPresentException Thrown when an application tries to access an enum constant by name and the enum type contains no constant with the specified name. Error An Error is a subclass of Throwable that indic...
Enum<E extends Enum<E>> This is the common base class of all Java language enumeration types. Float The Float class wraps a value of primitive type float in an object. InheritableThreadLocal<T> This class extends ThreadLocal to provide inheritance of values from parent thread to child thread...
UnrecoverableKeyException This exception is thrown if a key in the keystore cannot be recovered. UnresolvedPermission Legacy security code; do not use. Interfaces 展開資料表 Enums 展開資料表 SignatureState Enumerates values returned by several types....
out.println("result:" + divide(a,b)); } private static int divide(int a, int b) { if(b == 0) { throw new IllegalArgumentException("second argument cannot be zero."); } return a / b; } } OutputException in thread "main" java.lang.IllegalArgumentException: second argument cannot...
7164256 core-libs EnumMap clone doesn't clear the entrySet keeping a reference to the original Map 7166055 core-libs Javadoc for WeakHashMap contains misleading advice 7198073 core-libs (prefs) user prefs not saved [macosx] 8011200 core-libs (coll) Optimize empty ArrayList and HashMap ...