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1、Dw/home/sd0807/ Core Java note.txt1 & 44 sunN: SCJP:Ncore java SCJD:+jdbc+swingSCWCD:+servlet+jsp(JAVA EE) SCEA:+EJB+Webserver( )c0J#M!sM Xw;(z) | M !“x”7zYmain.K1#M!ATnc!cMJ9w public static void main(Stringargs).Jjarw1eclipseid!FDif-Export-MD|-Next-Next-dmainm!class-finish1jar!7Dif7zDiM“java -jar .
2、/D|.jar”iA9DJ“D|.sh”9sh!jJ“#MD”G-9shb0D CommentswcMiu+?Q/./* .*/D/* . */Dib5JDK!javadocf,%DN9J#M!RD5javadocHTML!#MD:javadocoptionspackagenamessourcefilesfilesgpw67%POm|!igp|w1. i“_”“$” b . “_”“$”2. M 3. “ ( f4. fQa (p5Q!gp iu Q|b5f,A)5. t5JavaBeans|i7um!q!i set get is add O remove gp | w1. %| T|w“!R
3、Mid+ 7“!RM ( ) class MyFirstClassinterface Weapon2. ” mE w 7“RMi+“M (uo!n) boolean isWomanvoid setName(String name)3. w Mp F“!Ji public final int GREENpublic final int HEAD_ COUNT4. Java(Package)w M package java.awt.eventjava.lang.System.gc(); / java.lang.Runtime.gc(); zB !tY, tU package q!w|fiuDq%0
4、in1qiA“ |.%|”import CACA9!%iwjavac-d !%|.javajava|.%|import java.util.*; /pCAjava.util!n%x import java.*; u%.C; “*”pCA!%i !%(b q)Dw/home/sd0807/ Core Java note.txt2 & 44 g 7gDy 7!&(public)%g D!&%iD| R!&%| g 7D 7YiibCAYg Ye!fc DD! 7g CAYe!fc D i71% g fYiCAYcDy!Yg CAYRDD!n%g 7D !&%g f!&%!Df | Aw5Scann
5、er NA1J2SE 5.0ib5java.util.Scanner%N55P!A b59f,! next() H iNh!AScanner s = new Scanner(System.in); System.out.printf( A= w %s n, s.next(); System.out.printf( A=.w %d n, s.nextInt();Aw5 BufferedReader N5A/5.0 !N _!m BufferedReader Ojava.io.Reader b5java.io.InputStreamReaderA: import java.io.InputStre
6、amReader;import java.io.BufferedReader;class npublic static void main(String args) System.out.println(A7Di zw);BufferedReader s = new BufferedReader(new InputStreamReader(System.in); String next;trynext = s.readLine();/TY i System.out.println( A=Dw + next);catch(Exception e).“mwS.z=;.zggzHg +1S.z.!g
7、(Hg+1)Hgz(=;.)B;.i011(B;)z9(;);.ix0x55(;)z5*16+5(;)%w.u.c%boolean (8bit,!)truefalsechar16bit,0216-1(216=6w6)byte8bit,-2727-1(27=128)short16bit,-215215-1(215=32768)int32bit,-231231-1 (2147483648,20t,10 .)long64bit,-263263-1 (900tt,20 .)float32bit,9 .i.(JA)(. i7 iSii)double64bit,18 .wfloat double !.bi
8、1-.i double i=0.01; if ( i - 0.01 short int long float doublecharwwoj%k(Q%)a,3iwintfloat; longfloat; longdouble. 7! n=;!p 0.1 !;a0ibjava.mathBigDecimal%!mQ%S%k%kwint ti; (byte) ti ;kiP|!iI“final”(“i9P7=inbAP!wfinal int n1= 10;n1=20;9nwSystem.out.println()Qk!System.out.print()wiQkSystem.out.printf()b
9、A % !A%,bA, A % !.uO1 printf ,5 %argument_index$flagswidth.precisionconversion “b”i F.$flags a.aprintf()!A=c#M!3 FormatterxA ScannerxSwwddd138;.Unicode(ddd)uxxxx1416;.Unicode(xxxx)bfnrt(g7),kkgik%d%f%e,%E%a,%A%o%x,%X%s,%S%c,%C%b,%B%t,%T%10;1.iByteShortIntegerLongOBigInteger%10;$.iQ!.cFloatDoubleO Bi
10、gDecimal10;$.i75viiQ!.cFloatDoubleOBigDecimalvi$.,16;1.,10;.,.u%(o)8;1.mi.u%:Byte,Short,Integer,LongOBigIntegerJ$.16;mi.u%JmiQ!.cByteShortCharacterO IntegertrueOfalse(%BTRUEOFALSE);Z,ztrue,z false”/!i1APID/*t!Unicode*/class Testpublic static void main(String args) String s= +0+a; /0=48,9=57/A=65,Z=9
11、0;a=97,z=122;z=32int i = s.codePointAt(0);int j = s.codePointAt(1);/9codePointAt(int index)mSystem.out.printf(%d %d,i,j);Dw/home/sd0807/ Core Java note.txt4 & 44 /*/!w+.z.+zwstr+10+20zzstr102010+20+strzz30str0iwi0iwI( +)(j)( * )b N0iw 2%3=2100%3=10iw( / )N( b )=+=j=*=/=%=(0f!iAo!;0ixint i=10;i-=3*5;
12、0-5)=-0iwD D= D D(g)NH z I1ANH(1 !g-1)f:fQ,f”!,yA%y!f7D2Niy A0( i) y i in.o iS.f 1233 12(33%32) z 121 =6xint 32 ij nfw1 17 Mi w x=y=z=5; 9nx,y,z.5!. 5.0iioj int %n!in!%if(+7double)doublexelse if(+7float)floatxelse if(+7long)longxelse int dwif(.).else.if(.).else if(.).if(.). if(.).!dit5 switchswitch(
13、char c)case c1: .; break;case c2: .; break;.default :.; /*switch! i int %k int !bwbyte,short,char,Integer,Short,Character,Byte long.%(float,double) Stringcase!cU%P(Integer,Character)*/Dw/home/sd0807/ Core Java note.txt5 & 44 Hwfor(;W ;U; ) HY;oC! for 7ifor ! 0 l.bM c booleanin 7cYfor H71H.M!3iwhile
14、().;do.; while ();wwdo y“”iwhile !ibpbreak continuebreak !Hi1UHi!7|Hcontinue 0 HiDJ;7!H bi &H9!Y continue 1H 9 break b1wgVip#MV(vwgU5i& )9DJAVA! goto Yww(?0!)H 9!Pi1H 0 iH 5 1Z7H 9bA 7o|!PiH ,for9! iwfor(int i=0;i10;i+).1 for H0A i i8for(int i=0;i10;i+). ! for(int i=0;i3;i+). H,H 8b for H 9!iR1 wint
15、 i;for (i=0; i10; i+).for HA i i+10( wabstractbooleanbreakbytecasecatchcharclasscontinuedefaultdodoubleelseextendsenumfalsefinalfinallyfloatforifimplementsimportinstanceofintinterface longnativenewnullpackage privateprotected publicreturnshortstaticsuperswitchsynchronizedthisthrowthrowstransient tru
16、etryvoidvolatile whileJava truefalse(,Uboolean%!Pn!(.Mifriendlyisizeofjava!(“wconstigoto w9,:wiP|“w%w7%!wumwu(C .):wStudent s ;9 Ks7 Student%!(DC+! ),7f7 nKT s ws = new Student();7V_z(8Dz)i8Dz“!7Student%!.uUs“!n8Dz!8DPw9z7V,Qa!i“.u!8Dz(s7P)7bStudent s = new Student3D7Qa 3 !Student%!.!APzPAPw117%im!P
17、x2!KSAPJ7%!Dw/home/sd0807/ Core Java note.txt6 & 44 3AP1fQKw1.u 0iW.u falsei % null AP! 1 % i+!%! b zPw11m9!PzP2zP5ciQ6zP3 z P! 1n1!gVi1w! 9z P|f wz PAP|i1z P! 9i+ DAPKbthis.AP|zP.!.!w.!.!“%!.!7.Pb.!i.!iw;:.!w1. 7int.!Pi.!P.! ! int nums;2. 7!.!i7J6Pnums nums = new int7;3. Dint.!77intnums0 = 6; nums1
18、 = 34; nums2 = 23; nums3 = 4; Q.!w1. mwtype Q. arrayNamexw int b = new int 2 1;2. v9z,mww7Qvz:int a = new int23x7Qvzint a = new int2 x /.bfi.7a0 = new int3;a1 = new int5;/aJ7Q.!bz!.!3. ,mw.!ivziw;(7MiOfor.)1.!;wint a = 2,3, 1,5, 3,4;javaQ.!7Q.!i.!7.!i.!.!Q.!Qa z .x(a.length=.x a0.length=.).!ZFmwInt
19、nums = 6,34,23,4,15,0, 57; (java)9m1!biAnums=.n=Int nums = new int 6,34,23,4,15,0, 57;9Y!7 int 9A.i?.qx9Yb int nums;AZ nums = new int. bkk i wInt nums; (C C+)ww short z ; /9w!i7Q.!.!i+x new .!b.!oj:byteshortintlong 0floatdouble 0.0char 0boolean false%null.! length :Dw/home/sd0807/ Core Java note.txt
20、7 & 44 p.!Qai9.!y“!.lengthNijava.lang.ArrayIndexOutOfBoundsException:(9.!g& !)?.wMath.random(); /b?!01 !.,CA Random r = new Random(); num = r.nextInt(100);100?.CA import java.util.Random;bw1#MM9YiUCAjava.util.Random r = rnextInt(2);02 !?.i0 2Arrays.sort(.!|)MiCA impor java.util.Arrays;.!:1. for YiJ.
21、!j wwJ.! a = .!b;Jb! 6a2. System.arraycopy();arraycopy(Object src, int srcPos, Object dest, int destPos, int length)src - .!srcPos - .!dest - qg.!destPos - qg.u!length - !.!.wSystem.arraycopy(a, 0, b, 0, a.length);/.! a.! b 1java(OO)!1k1!i(w!7p1i-B)x2kWwmb5.m.,7S!.%Ml.;bJP.A,%5km!()ws!GiU;!GJavai!YM
22、1. :(argument_list)throws A wpublic String getName()return name;2. f4 i4%c void3. xmf4%4. 4%cm|i+ ibk Dw/home/sd0807/ Core Java note.txt8 & 44 .l1javam#W%li%lll!.u!l l!“.u!8DJava5,9wm5!n.!Timl6!.P!9%!.l!m7PPirP!mO!Jm!.zPiws“m!.;i.Q VS w(.)wD.(Java.m)!zP1.i7A!i.0 ,#M+!P(5Po|), !PiHi w. i6. .!.u(Overl
23、oad)17%i 17!|.i!.b .ib.!%O.i b%.!M 1 m|i.2miD.!vn1%(9bfhz)x3um|m!57%mD.xJ!D !5Pi! !5P.Z6 iU, 9 g4Java!0ijava7!0iString%!“+”ii%+String%0.Stirng%5 w wz17%i b1% !m |!mm! (Override) MDiP%D!m1. !m| . 4%(Java 5 i4%b%)2. n3. n (bnTOn! G iOP G ) (extract Method)=g!ig!bQ1(!gib!gV!mEJf,%(f,%Jf,)i7.mif1eclipse
24、id!gifRefactor-Extract Mathod O(Shift+Alt+M)!U1vz23xmwxmxfi1!”9xm7xm(Nday05! TestCat.java)xm1J!#!mixm7new !xm1wf4(voidf)im|%|(I void PJrm)21Mxmi!xm30J1%gIxm!Xwpublic ClassName()Dw/home/sd0807/ Core Java note.txt9 & 44 xm b+! hhprivate protected default private 7 1 singleton G17!J”xm7i79Ji9xm* T Aifx
25、mbxxmixm!.7iO.MD!xmw- xm!5xm !wg xmi7xmJ.! s7 Mf.!xm|,M=7.!xmi7 7f.!xmi cgQxM %7!xm,.77iKbj9Fxm J( KQ=!xmi!xm=9%D i %xm?%!xmn xmbr this Z7xm(this T c1 7Y)|wiw!mU!Y)w person p1 = new person; p1.shout();MJw new person.shout(); /TmiT| nPJ=zB 5| !3iw1. T 7 m2. T67.this (Nday05 !TestThis.java)mi197 nm! x
26、.ix! thisAPz Pthis.AP| z zP|(JzP6AP)this()p%!+xmi17m!77YxmbrthisZ7xm(thisTc17Y)*super (.ix!%c1xm!7!-7ci- !8D!78Dipn!wE(Encapsulation)D(Inheritance)polymiorphismEw1kw7!9i!i(amumiU(aE5!P!,yE!gn,bbQ2k%wE5!wb!iuvR!get/setmi!mwb!e!7ei!7!3km!U5m!P!,y4kprivate:z%Jbdefault:%h%b(oj)protected:%hh!%public:!w9!o%n1!5 E w i7QR!get/setm w1kB!9#feDw/home/sd0807/ Core Java note.txt10 & 44 2kQ7!&!Thhe.u3kbQ7Dw1 wD71!%x7f%D1!%n9Q%!mi1Ti8b1f%I7Qf!m2 %7 o!(3 D( extendsdog extends Animal :p%D=Q%4 JavaD(javaW! )%