java_JavaSE知识点记录

1、/ NetMeeting - -conf / IP - -TCP/IP-ipconfig cd dir d: - - - - Path Path Pathavi classpath1Java java-class-ClassLoader(lazy load- (verifier- (interpreter JVM (Compile Once, Run Anywhere Garbage Collector (GC classpath path classpath JVM . java class ×××× HelloWorld one public cla

2、ss in a java file zero or many non-public classin a java file public class name = file name Error Compile Time Error Runtime Error 1 24 google5 BBS6 teacher2boolean true false char Unicode utf-16 / /16 byte short int( long float double(default BigDecimal code - data - stack - heap - new boolean byte

3、 short char int int - long - float - double ( +-*/% + - > < >= <= = != & | ! && | &1 1 | 1 1 1 >> /2 << *2 >>> = += -= + String String x ? y : z if 3if (. ; for(.;.;. while . do while ( ; break continue 1! + 2! + + 10! 1.100 3 101.200 switch case brea

4、k12 copy34 main Fab41 2 3 polymophism, dynamic bind, late bind, runtime bind java class Java class JDK class%JAVA_HOME%/jre/lib/xxx.jar (rt.jar new new5void ClassLoader 1 find class using classpath 2 lazy load TestBirthdate TestCircle * : TestCircle 1 2 3 4 5 6 modifier 7 TestPoint 1: contains 2: 3:

5、 4 Point public boolean containedBy(Circle c return c.containts(this; 1 2 3 4 this this this6setclasspath=%classpath%;D:share01_J2SEjavachapter_3 testpackage echo %classpath%12 1 23 * ( JDK5.07classpath ( xx.java xx.class class package class classpath class classpath classpath classpath jar setclass

6、path=%classpath%;xxxx/xxxx/xxx/xx.jar classpath "." classpathjava.lang rt.jar classpath * access modifiers private default/package protected public class inner class public default/package public private protected default private 50% public 30-40 protected 5-10 extends java C+ java interfa

7、ce C+ copy /Annotation Annotation Override8Override super- super + ( Super ( this( * : Teacher Person * : Student Person Object JavaDocs APIApplication Programming Interface finallize JNI java native interface equals " " String s = newString("aaa" hashCodeinstanceof toString( has

8、hCode hashCode hashCode clone(deep-copy light-copy getClass Class ClassLoader Load Class class9instanceof a instanceof XX a XX XX (polymophism dynamic binding, late bind, runtime bind (extensibility Game/Test.java 1 2 3 4 * final final final final abstract method and class abstract method abstract m

9、ethod abstact class Abstract class cant be instantiated abstract interface public static final public abstract implements Valuable.java interface i public static final , ac ac i10demeter11catch catch finally throw throws throws printStackTrace ( / Java src / src.zip Exception RuntimeException ( Runt

10、imeException NullPointerException 12 java API TestDateSort.java Comparable 3 1 1. 5. 13 3 TestArgs * * 2. 1 6. 192.38 3. 4. API String StringBuffer StringBuilder StringBuffer StringBuilder 2 Math Enum interface 14 Map 1 3 public static final int L = 1; Collection Set List Collection c = new ArrayLis

11、t( Hash equals hashCode ByteArrayOutputStream InputStreamReader / OutputStreamWriter DataInputStream / DataOutputStream PrintStream / PrintWriter ObjectInputStream / ObjectOutputStream 18 Implements runnable /(recommended Extends Thread / / / / Isalive run Set get priority Start Stop Join Sleep getN

12、ame Yield sychronized dead lock TestDeadLock.java live lock producer consumer wait notify notifyAll / ProducerConsumer.java while if class A synchronized m1(; m2(; synchronized m3(; Aa 1:a.m1 a.m3 ( m1 wait m3 2:a.m1 a.m2 wait sleep wait wait sleep 19 TCP/IP IP TCP/UDP Socket TCPSocket BindException talkserver talkclient UDP * TestUDPServer TestUDPClient 20 Component Container Window Panel Frame Dialog Frame Panel Frame new vs extends Frame(Recommended FlowLayout Panel GridLayout BorderLayout Frame / Button ActionEvent TextField ( Window * TFMath : graphics paint paint MyMouseA