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JDK1.5新特性:
Integer iObj = 3;System.out.println(iObj + 12);Integer i1 = 137(-128--127范围时,为true);Integer i2 = 137(-128--127范围时,为true);System.out.println(i1 == i2); //false,但是括号中时却返回ture,原因是Integer采用的是享元模式Integer i3 = Integer.valueOf(213);Integer i4 = Integer.valueOf(213);System.out.println(i3==i4);//同上,另一种包装形式
public class EnumTest {/*** @param args*/public static void main(String[] args) {WeekDay1 weekDay = WeekDay1.MON;System.out.println(weekDay.nextDay());WeekDay weekDay2 = WeekDay.FRI;System.out.println(weekDay2);System.out.println(weekDay2.name());System.out.println(weekDay2.ordinal()); System.out.println(WeekDay.valueOf("SUN").toString());System.out.println(WeekDay.values().length);new Date(300){};}public enum WeekDay{SUN(1),MON(),TUE,WED,THI,FRI,SAT;private WeekDay(){System.out.println("first");}private WeekDay(int day){System.out.println("second");}}public enum TrafficLamp{RED(30){public TrafficLamp nextLamp(){return GREEN;}},GREEN(45){public TrafficLamp nextLamp(){return YELLOW;} },YELLOW(5){public TrafficLamp nextLamp(){return RED;} };public abstract TrafficLamp nextLamp();private int time;private TrafficLamp(int time){this.time = time;}}}
import static java.lang.Math.*;public class StaticImport {public static void main(String[] args){int x = 1;try {x++;} finally {System.out.println("template");}System.out.println(x);System.out.println(max(3, 6));System.out.println(abs(3 - 6));}}
public class VarableParameter {/*** @param args*/public static void main(String[] args) {System.out.println(add(2,3));System.out.println(add(2,3,5)); }public static int add(int x,int... args){int sum = x;/* for(int i=0;i
ReflectPoint pt1 = new ReflectPoint(3,5);BeanInfo beanInfo = Introspector.getBeanInfo(pt1.getClass());PropertyDescriptor[] pds = beanInfo.getPropertyDescriptors();Object retVal = null;for(PropertyDescriptor pd : pds){Method methodGetX = pd.getReadMethod();retVal = methodGetX.invoke(pt1);}
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