http断点续传简单实现（java)

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0 发表于: 2006-05-10

/*
**SiteFileFetch.java
*/
package NetFox;
import java.io.*;
import java.net.*;

public class SiteFileFetch extends Thread {

SiteInfoBean siteInfoBean = null; //文件信息Bean
long[] nStartPos; //开始位置
long[] nEndPos; //结束位置
FileSplitterFetch[] fileSplitterFetch; //子线程对象
long nFileLength; //文件长度
boolean bFirst = true; //是否第一次取文件
boolean bStop = false; //停止标志
File tmpFile; //文件下载的临时信息
DataOutputStream output; //输出到文件的输出流

//负责整个文件的抓取，控制内部线程（FileSplitterFetch类）
public SiteFileFetch(SiteInfoBean bean) throws IOException
{
siteInfoBean = bean;
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath()));
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info");
if(tmpFile.exists ())
{
bFirst = false;
read_nPos();
}
else
{
nStartPos = new long[bean.getNSplitter()];
nEndPos = new long[bean.getNSplitter()];
}

}

public void run()
{
//获得文件长度
//分割文件
//实例FileSplitterFetch
//启动FileSplitterFetch线程
//等待子线程返回
try{
if(bFirst)
{
nFileLength = getFileSize();
if(nFileLength == -1)
{
System.err.println("File Length is not known!");
}
else if(nFileLength == -2)
{
System.err.println("File is not access!");
}
else
{
for(int i=0;i<nStartPos.length;i++)
{
nStartPos = (long)(i*(nFileLength/nStartPos.length)); )TRDM[u
} }Z0)FU+
for(int i=0;i<nEndPos.length-1;i++) e<iTU?eJM
{ q.Z0Q
nEndPos = nStartPos[i+1]; }@1LFZx
} GbB&kE3KP
nEndPos[nEndPos.length-1] = nFileLength; 6kIq6rWF9
} eUF PzioW
} IQ2<Pinv
ELY$ ]^T
2z )h,<D
//启动子线程 ,ZMYCl]
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; yU .B(|
for(int i=0;i<nStartPos.length;i++) szmjp{g0
{ #cjB <APY
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ^9cqT2:t
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), {Z-5
nStartPos,nEndPos,i); JhB{aW>
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); M&Ycw XV:Z
fileSplitterFetch.start(); q' _
} :V+t|@m5l
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), `pII-dSC%
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ':.d,x)
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", qDcl;{L
nEndPos = " + nFileLength); *2;w;(-s
// fileSplitterFetch[nPos.length-1].start(); ]S;e#u{QE
MzJ5_}
"uZ'oN
//等待子线程结束 8&dmH&
//int count = 0; "* 'rzd
//是否结束while循环 w5qhKu!1
boolean breakWhile = false; v[F_r
ukG1<j7.
1AoBsEnd
while(!bStop) dQ;rO$co
{ M}38uxP
write_nPos(); ^@{'! N
Utility.sleep(500); DrMcE31
breakWhile = true; w :^b3@gd
[DjdR_9*I
}o)GBWqHR
for(int i=0;i<nStartPos.length;i++) (qohb0
{ ,:=E+sS
if(!fileSplitterFetch.bDownOver) "#[Y[t\Ia
{ x`C;
breakWhile = false; k`\DC\0RG
break; nwO;>Qr
} ckhW?T>l
} tk1qgjE(?
if(breakWhile) {wA@5+[
break; BT`/OD@
< >f12pu
{yspNyOx
//count++; /\#qz.c2K
//if(count>4) N;Hf7K
// siteStop(); %v}:#_va]
} .HGEddcC
8V~w3ssz
XPWK"t01
System.err.println("文件下载结束！"); mYa0_P%^
} ~^Vt)/}Q
catch(Exception e){e.printStackTrace ();} HnOp*FP
} ''f
A:NsDEt
7cvbYP\<lv
//获得文件长度 hnE@+(d=qJ
public long getFileSize() $7|0{Dw
{ B;G|2um:$
int nFileLength = -1; {#Gr=iv~N
try{ `[o^w(l:5@
URL url = new URL(siteInfoBean.getSSiteURL()); 8a-[Q
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); S~Nx;sB
httpConnection.setRequestProperty("User-Agent","NetFox"); C7qbofoV
of{wZU\J+9
L & PhABZ
int responseCode=httpConnection.getResponseCode(); LuQ=i`eXx
if(responseCode>=400) u!{P{C
{ nM}X1^PiK"
processErrorCode(responseCode); '1.T-.4>&
return -2; //-2 represent access is error {u9VHAXCf
} 6Y}#vZ
2psLX
,F:l?dfB\I
String sHeader; qx`*]lX
,Sz*]X
"d.qmM
for(int i=1;;i++) ! daXF&q
{ oSy[/Y44a
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); +-8uIqZ
//Utility.log(in.readLine()); CE*@CkC0z
sHeader=httpConnection.getHeaderFieldKey(i); ;t*45
if(sHeader!=null) xj%h-@o6
{ b.ow0WYe
if(sHeader.equals("Content-Length")) (A(d]l
{ D&N5)
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); t3U*rr|A
break; nC[L"%E|se
} npbNUKdz
} na8A}\!<
else skZxR5v3~L
break; WnHf)(J`"
} \[Rh\v&
} cB?HMLbG>
catch(IOException e){e.printStackTrace ();} >cSc
catch(Exception e){e.printStackTrace ();} *K m%Vl
{\lu; b!
rxm!'.+
Utility.log(nFileLength); vco:6Ab$
X$%RJ3t e
ZH~m%sA
return nFileLength; M@{GT/`Pf
} X "1q$xwc
}$iH3#E8
n*bbmG1
//保存下载信息（文件指针位置） KvktC|~?
private void write_nPos() hQl3F6-ud
{ 46}/C5
try{ PtmdUHvD
output = new DataOutputStream(new FileOutputStream(tmpFile)); BnAia3z
output.writeInt(nStartPos.length); Eiz\Nb
for(int i=0;i<nStartPos.length;i++) LFg<j1Gk`
{ Pme`UcE3H
// output.writeLong(nPos); 3go!P])
output.writeLong(fileSplitterFetch.nStartPos); rq2XFSXn
output.writeLong(fileSplitterFetch.nEndPos); o.Q|%&1
} =_L"x~0I-
output.close(); 1Qf5H!5vx
} [ &R-YQ@
catch(IOException e){e.printStackTrace ();} t{84ioJ"$
catch(Exception e){e.printStackTrace ();} 0)9GkHVu(
} uX`Jc:1q3
Cw Z{&
yUEUIPL
//读取保存的下载信息（文件指针位置） !|Vjv}UO
private void read_nPos() u%h]k ,(E
{ |h6)p;`gc
try{ : <m0 GG
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); u5T\_0
int nCount = input.readInt(); %2/WyD$U
nStartPos = new long[nCount]; D~2,0K
nEndPos = new long[nCount]; #lV&U
for(int i=0;i<nStartPos.length;i++) m,)Re8W-
{ 97$y,a{6
nStartPos = input.readLong(); ScM2_k`D
nEndPos = input.readLong(); F"a,[i,[W
} I uhyBo
input.close(); )`;?%N\
} M# S:'WN
catch(IOException e){e.printStackTrace ();} "$ u"Py
catch(Exception e){e.printStackTrace ();} +J.^JXyp0
} 5l{_E:.1
I>ofSaN
8kO|t!?:U
private void processErrorCode(int nErrorCode) a)`h*P5@
{ .Jou09+
System.err.println("Error Code : " + nErrorCode); |$6GpAq!
} uQpV1o5iA
_Se>X=
Xo]FOJ5
//停止文件下载 d{9jd{ _#G
public void siteStop() 7J0PO}N
{ (K0FWTmm
bStop = true; KOwEw~
for(int i=0;i<nStartPos.length;i++) ,uDB]
fileSplitterFetch.splitterStop(); :vV?Yv%P)n
bpKb<c
?WUu@Z
} #(XP=PUj
} iCz,|;w%
//负责部分文件的抓取 =o+t_.)N
**FileSplitterFetch.java Lqwc:%Y:_
*/ g($y4~#
package NetFox; Qv']*C[!z
nA%-<
-+O8v;aC'
import java.io.*; k('2K2P
import java.net.*; &b{L|I'KYT
.,tf[w 71
Lo9+#ITyx
public class FileSplitterFetch extends Thread { ^Z\1z!{R
kdgQ -UN$
3#5sj >
String sURL; //File URL =Z%&jul
long nStartPos; //File Snippet Start Position K<\TF+
long nEndPos; //File Snippet End Position >f}rM20Vm
int nThreadID; //Thread's ID b"{7f
boolean bDownOver = false; //Downing is over Uv5E$Y"e10
boolean bStop = false; //Stop identical !U=;e?o
FileAccessI fileAccessI = null; //File Access interface y{"8VT)
L88oh&M
8G(wYlxi
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ;~xkT'
{ /XnI>
this.sURL = sURL; &hqGGfVsd
this.nStartPos = nStart; U .G*C
this.nEndPos = nEnd; 5RZAs63t
nThreadID = id; <R_3;5J%
fileAccessI = new FileAccessI(sName,nStartPos);//定位 %o*afd
} >W 8!YOc
.XYSO
[+ 1([#
public void run() )mp0k%
{ VYlg+MlT0
while(nStartPos < nEndPos && !bStop) =C5[75z#+
{ h:j-Xd$H+
nD E5A
H^'EY:|
try{ .>h|e_E
URL url = new URL(sURL); VZw("a*TB
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); >;0z-;k6
httpConnection.setRequestProperty("User-Agent","NetFox"); 4[rD|
String sProperty = "bytes="+nStartPos+"-"; !"p,9
httpConnection.setRequestProperty("RANGE",sProperty); !4-NbtT
Utility.log(sProperty); Z`< +8e
]3Mm"7`
F~<$E*&h@
InputStream input = httpConnection.getInputStream(); e|]g?!
//logResponseHead(httpConnection); ezHj?@
Nb(se*Y#
B/pNM81(
byte[] b = new byte[1024]; cUS2*7h
int nRead; `(Ei-$ >U&
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 6n;ewl}
{ N[zI@>x
nStartPos += fileAccessI.write(b,0,nRead); 42Ql^ka
//if(nThreadID == 1) $mp7IZE|
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Lf7iOW9U3
} */?L_\7
x{RTI#a.
$"x(:
Utility.log("Thread " + nThreadID + " is over!"); dp_J*8
bDownOver = true; oLBpG1Va
//nPos = fileAccessI.write (b,0,nRead); WMl_$Fd6
} .DCp)&m l;
catch(Exception e){e.printStackTrace ();} }RW4
} BOfO$J}
} YHCXVu<.b
\h_hd%'G
${e(#bvGZ
//打印回应的头信息 tHhY1[A8m
public void logResponseHead(HttpURLConnection con) 6S]GSS<
{ [yjC@docH
for(int i=1;;i++) iY.~N#Q
{ `M"b L|[R
String header=con.getHeaderFieldKey(i); "eGS~-DVK
if(header!=null) p72+:I
//responseHeaders.put(header,httpConnection.getHeaderField(header)); E/AM<eN
Utility.log(header+" : "+con.getHeaderField(header)); }{E//o:Ta
else [xM07%:
break; SLZv`
} ~+^,o_hT
} p|Z"< I7p(
/"Rh bE
KasOh"W.P
public void splitterStop() +Y 3_)
{ 0-FwHDxw
bStop = true; 7B+?1E(
} h :NHReMT
A+Z3b:}~
$W` &7
} :GGsQ n
D {>,2hC
0Wv9K~F
/* Tz%l9aC
**FileAccess.java ,3N8
*//文件访问(定位，写) j>0S3P,
package NetFox; /A##Yv!biR
import java.io.*; 8>O'_6Joj
Rp.@
;|9VPv/
public class FileAccessI implements Serializable{ AGrGZ7p]
F fl`;M
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 =>-b?F0(c
RandomAccessFile oSavedFile; Zj`eR\7~
long nPos; TX;OA"3=\-
%'^m6^g;
.8.ivfmJh
public FileAccessI() throws IOException )@))3
{ ?86h:9
this("",0); Bg7?1m
} <J`_Qc8C
{"4t`dM
@/|sOF;8W
public FileAccessI(String sName,long nPos) throws IOException swlxV@NQ
{ ^_2Ki
oSavedFile = new RandomAccessFile(sName,"rw"); NW!e@;E+i
this.nPos = nPos; Km\M/j|
oSavedFile.seek(nPos); Uc7X)
} x1A^QIuxO
AO^F6Y/
Y^3tk}yru
public synchronized int write(byte[] b,int nStart,int nLen) X3a:*1N
{ b/ZX}<s(1=
int n = -1; :(I)+;M}P
try{ !?Ow"i-lp
oSavedFile.write(b,nStart,nLen); _k6N(c2Nd
n = nLen; 4Ag+
} U.>n]/&
catch(IOException e) ,9W0fm\t
{ vi lNl|
e.printStackTrace (); ,wZ[Y 3
} xB9^DURr\
R<JI
Hi.JL
return n; >@]E1Qfe
} ;'p0"\SV
73N%_8DH
a.w,@!7
} 1d-j_H`s
%NxNZe
<NS=<'U
/* xbn+9b
**SiteInfoBean.java 4b7}Sr=`
*/ S0p]:r";x
package NetFox; E 8,53$
EHo"y.ODg
Qj3UO]>
public class SiteInfoBean { 17};I7
G_dia6
*OsXjL`f
private String sSiteURL; //Site's URL O#u)~C?)8
private String sFilePath; //Saved File's Path ~ RTjcE
private String sFileName; //Saved File's Name @h^5*M
private int nSplitter; //Count of Splited Downloading File gdkO|x
p4aM`PW8>=
5!y3=.j
public SiteInfoBean() W>1\f0'
{//nSplitter的缺省值为5 rEddX
//default value of nSplitter is 5 S93NsrBbY
this("","","",5); C"0gAN
} bS0^AVA
QouTMS-b
/B}]{bcp$
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Fb-NG.Z#
{ LM*9b
sSiteURL= sURL; CR, Y%0vQ
sFilePath = sPath; a?+) K
sFileName = sName; RsrZ1dhPvV
this.nSplitter = nSpiltter; ?%;uR#4
3zh'5qQ
kTFN.kQx@
} 1u&P,&T
C,fIwqOr3
M_*w)<
public String getSSiteURL() e@F&/c
{ g:f0K2)\r:
return sSiteURL; q:?g?v
} 0imz}Z]
uy`U1>
'# (lq5 c
public void setSSiteURL(String value) ?$r+#'asd(
{ 3&2,[G04
sSiteURL = value; U?>zq!C&R
} V(w[`^I>~
^P{'l^CVX
*23
public String getSFilePath() ,pAMQ5
{ *wh'4i}u
return sFilePath; aD3$z;E
} ;7 IVg[f
Y-9]J(
1J<-P9 vk+
public void setSFilePath(String value) :ye)%UU"|:
{ IM +Dm
sFilePath = value; VN$#y4
} @br%:Nt
L^ +0K}eD
75^-93
public String getSFileName() jhg!K.A
{ A;Zg:
return sFileName; JaIj9KLNX
} }i/{8OuW
0Fi7|
?BWWb
public void setSFileName(String value) 3QXGbu}:h!
{ KTf!Pf?g
sFileName = value; 2etlR
} T /]ayc:
'{7A1yJnY%
kg !@i7
public int getNSplitter() +<3tv&"
{ ]B5\S
return nSplitter; O+'Pq,hn
} @aj"12
5_`.9@eh.
/&kTVuN"(
public void setNSplitter(int nCount) ,'ndQ{\9
{ XeZv%` ?
nSplitter = nCount; ?G8 D6
} kdoE)C
} wvUph[j}J
("{AY?{{
$s) ^zm~
/* j"YJ1R-5
**Utility.java Q |l93Rb`
*/ lGcHfW)Y
package NetFox; 67n1s
x#ouR+<
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public class Utility { ]-ZD;kOr
y:W$~<E`p
g`1*p|
public Utility() `NGCUGQ_7
{ 4!monaB"e
6 #QS5
1F$a My?
} YemOP9
{8UBxFIM(
//线程睡眠 ^U`[P@T
public static void sleep(int nSecond) 0<^K0>lm p
{ Kh5:+n_X
try{ KzM\+yC
Thread.sleep(nSecond); aV>w($tdd
} xDVzHgbf
catch(Exception e) -6
{ @AyC0}
e.printStackTrace (); mFo6f\DHr`
} ZNuyGo;
} Y RA[qc
dXdU4YJX
//日志 sN;U,{
public static void log(String sMsg) yJKezIL\z
{ w[VWk
System.err.println(sMsg); sA` bPhk
} N>gv!z[E
Ii4Byyfx
HD`Gi0
public static void log(int sMsg) R)<>} y
{ 3J[P(G>Q
System.err.println(sMsg); ;w@:
} ~xXB !K~C
} >j$f$*x
s2d;601*b
9@:&E
/* uQ&xoDCB
**TestMethod.java -gC=%0sp\
*/ .JH3,L"S^
package NetFox; !>2s5^JI9
-R:1-0I$
[bv.`
public class TestMethod { xeu] X|,
n#x{~oQc
3[8'pQ!&
public TestMethod() <xc"y|7X
{ ///xx/weblogic60b2_win.exe qWP1i7]=/
try{ Y$'fds4P
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); sG^b_3o)A
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); :v&GAs6H
SiteFileFetch fileFetch = new SiteFileFetch(bean); _b#9^2o
fileFetch.start(); FiIN\
} !H.&"~w@
catch(Exception e){e.printStackTrace ();} u}u2{pO!
3K54:
9{>m04888
} Nf$Y-v?i
Q<78<#I
8LiRZ"
public static void main(String[] args) OP<@Xz
{ wRLkO/Fw
new TestMethod(); Kj'm<]u
} GR|Vwxs<@P
} &<v#^2S3
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