的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n ajax Java Java 2000 4500 4000 7000 7000 1 2 3 4 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n blog blog blog Java 1 Java io 97 java public public 10 i 10 i for int j 0 j 10 j System out println i i j j if j 5 break ok boolean found false for int i 0 i 10 i for int j 0 j 10 j System out println i i j j if j 5 found true break 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 42 switch byte long String switch expr1 expr1 int Integer byte short char int long String sitch int swtich 25 short s1 1 s1 s1 1 short s1 1 s1 1 short s1 1 s1 s1 1 s1 1 int short s1 short s1 1 s1 1 java java 55 char char Unicode unicode char unicode char unicode char 44 2 8 2 3 n 2 n 8 3 cpu 2 8 2 3 2 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n byte 1 128 127 1 11111111 1 Java 1 11111110 byte 11111110 2 128 10000000 128 Java 1 00000000 byte 00000000 0 Java byte int a Integer MAX VALUE int b Integer MAX VALUE int sum a b System out println a a b b sum sum long int 2 31 2 1000 1000 1000 20 public class BigInteger int sign byte val public Biginteger String val sign val public BigInteger add BigInteger other public BigInteger subtract BigInteger other public BigInteger multiply BigInteger other 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n public BigInteger divide BigInteger other jdk java math BigInteger 112 final final final StringBuffer a new StringBuffer immutable a new StringBuffer a append broken public void method finalStringBufferparam param append a 101 equals Objet obj new Object obj new Object 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n equals String a new String foo String b new String foo new a b a b a b false a equals b true String input input equals quit equals equals Object equals Object equals boolean equals Object o return this o equals equals Object equals false equals 104 static staticVar staticVar 1 instanceVar instanceVar instanceVar 1 public class VariantTest public static int staticVar 0 public int instanceVar 0 public VariantTest staticVar instanceVar System out println staticVar staticVar instanceVar instanceVar 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 106 static static static static static static static static static static 1 Integer int int java 8 Java Integer java int int 0 Integer null Integer 0 int 0 Integer JSP Integer null el int 0 el 0 int web Integer Integer 26 Math round 11 5 Math round 11 5 Math ceil floor round ceil Math ceil 11 3 12 Math ceil 11 3 11 floor Math ceil 11 6 11 Math ceil 11 6 12 round Math floor x 0 5 0 5 Math round 11 5 12 Math round 11 5 11 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 1 public private protected friendly package package public protected friendly private 4 4 14 Overload Override Overloaded Overload Override Overload Override Overloaded Overloaded Override map remove key remove java 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 40 Constructor override Constructor Override Overload 34 implements concrete class main implements main java 107 clone clone super clone 6 4 1 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n Person class Person String name int age UserDao userDao daofactory getDao UserJdbcDao UserHibernateDao userDao userDao insertUser UserJdbcDao insertUser UserHibernateDao insertUser UserDao userDao daofactory getDao userDao insertUser user 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 102 java 17 abstract class interface abstract class abstract abstract abstract class abstract class abstract class abstract interface public abstract public static final 1 2 3 4 public protected public public abstract 5 6 public static public static 7 Servlet Servlet service public abstract class BaseServlet extends HttpServlet publicvoidservice HttpServletRequestrequest HttpServletResponseresponse throws IOExcetion ServletException if try 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n doService request response catch Excetpion e protected abstract void doService HttpServletRequest request HttpServletResponse response throws IOExcetion ServletException protected public class MyServlet1 extends BaseServlet protectedvoiddoService HttpServletRequestrequest HttpServletResponseresponse throws IOExcetion ServletException Servlet 6 37 abstract method static native synchronized abstract method static static native abstract FileOutputSteam api windows c jdk FileOutputStream open private native void open String name throws FileNotFoundException synchronized abstract synchronized 的T的T的T的T 问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n问ttp查 www客it部ast客部n 3 c public