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)); ! fl4"
} dF@)M
for(int i=0;i<nEndPos.length-1;i++) +}kgQ^
{ >,5i60Q
nEndPos = nStartPos[i+1]; #/-_1H
} `dkV_ O0
nEndPos[nEndPos.length-1] = nFileLength; 2Aq~D@,9=:
} N/F$bv
} h0|}TV^UJ
6[ga$nF?
2W<n5o
//启动子线程 <z)m%*lvU
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; g.DLfwI|
for(int i=0;i<nStartPos.length;i++) qRB7Ec_
{ DtxE@,
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), )P Jw+5
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), >)nS2bOE
nStartPos,nEndPos,i); t;q7t!sC]
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); nvq3*
fileSplitterFetch.start(); JMa3btLy(
} V%ii3
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), iz^qR={bW
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); IyUdZ,ba
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", UE0$ o?
nEndPos = " + nFileLength); C*kK)6v`
// fileSplitterFetch[nPos.length-1].start(); Kuw^qX"
ocRdbmS
[3>GGX[Ic
//等待子线程结束 [0;buVU.
//int count = 0; 6z,Dyy]tl
//是否结束while循环 GF<[}
boolean breakWhile = false; V2d,ksKwn
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+Wn&,?3^
while(!bStop) %:9oDK
{ 0~WF{_0|
write_nPos(); J5p8nmb
Utility.sleep(500); gBw^,)Q{0Y
breakWhile = true; '?5j[:QY@
-apXI.
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for(int i=0;i<nStartPos.length;i++) DocbxB={I
{ z%d#@w0X1
if(!fileSplitterFetch.bDownOver) `#s#it'y
{ ~W#sTrK
breakWhile = false; Gwec4D
break; :' #\
} ii|?;
} s95F#>dr
if(breakWhile) m?CZQq,
break; 4mYCSu14:`
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s|yVAt|=
//count++; @tUoD>f
//if(count>4) #Z,E><t
// siteStop(); ':h =*v8a
} 47By`Jh71
T2'RATfG
1+kE!2b;b
System.err.println("文件下载结束！"); mqtg[~dNc
} s}5+3f$f
catch(Exception e){e.printStackTrace ();} .8gl< vX
} f i~I@KJ>
-6~'cm
QrYa%D+
//获得文件长度 XVVD 0^ Q
public long getFileSize() "E*e2W
{ "9y( }
int nFileLength = -1; \1%l^dE@
try{ vv0Q$ O->
URL url = new URL(siteInfoBean.getSSiteURL()); x34f9! 't
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); VRng=,
httpConnection.setRequestProperty("User-Agent","NetFox"); -%c<IX>z9
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Do7=#|bAM
int responseCode=httpConnection.getResponseCode(); Vzlh+R>c
if(responseCode>=400) uBnoQ~Qd[z
{ K!z`
processErrorCode(responseCode); p]G3)s@>
return -2; //-2 represent access is error w!^~<{Kz
} G7LIdn=
]2SF9p_
\fWW'
String sHeader; 'cZN{ZMWG
4\otq%Y
"h"NW[R
for(int i=1;;i++) T<b+s#n4
{ []kN16F
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); A#h/B+
//Utility.log(in.readLine()); |AhF7Mj*
sHeader=httpConnection.getHeaderFieldKey(i); -~f511<
if(sHeader!=null) ]B\H~Kn
{ KP"%Rm`XN
if(sHeader.equals("Content-Length")) `_X;.U.Mv
{ 1=}qBR#scY
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); m6mwyom.
break; ~g;
} d' >>E
} px''.8
else X"MU3]
break; ->{d`-}m'
} <W)u{KS#TY
} x*XH]&V
catch(IOException e){e.printStackTrace ();} wE\3$ s/{D
catch(Exception e){e.printStackTrace ();} sq/]wzT:
eet Q}]
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Utility.log(nFileLength); (7FW9X;
~ Hy,7
,FzeOSy'p
return nFileLength; Y k7-`
} Kn;D?ioY
&BE g
vV?rpe|%
//保存下载信息（文件指针位置） arK_oh0B
private void write_nPos() {No L
{ a`Qot
try{ XM1`x
output = new DataOutputStream(new FileOutputStream(tmpFile)); qO1tj'U<
output.writeInt(nStartPos.length); \00DqL(Oj`
for(int i=0;i<nStartPos.length;i++) vxQ8t!-u
{ ~V=<3X
// output.writeLong(nPos); q%>'4_
output.writeLong(fileSplitterFetch.nStartPos); t(!r8!c u}
output.writeLong(fileSplitterFetch.nEndPos); K4Dp:2/K%
} {svn=H /
output.close(); Y/ot3[
} WG71k8af
catch(IOException e){e.printStackTrace ();} SO\/-]9#
catch(Exception e){e.printStackTrace ();} Q^Ql\
} _,74)l1
">81J5qgd
az;Q"V'6
//读取保存的下载信息（文件指针位置） tvKAIwe
private void read_nPos() T GB_~Bqe
{ BG&cQr
try{ "t=hzn"~%
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Joe_PS
int nCount = input.readInt(); :G w~7v_
nStartPos = new long[nCount]; R8ONcG
nEndPos = new long[nCount]; oPKr* `'
for(int i=0;i<nStartPos.length;i++) K0+.q?8D|
{ owpWz6k7
nStartPos = input.readLong(); 3-n19[zk
nEndPos = input.readLong(); 4674SzL
} r,P1^uHx
input.close(); b^c9po
} ?|{XZQ~
catch(IOException e){e.printStackTrace ();} CWo1.pVw
catch(Exception e){e.printStackTrace ();} '|>9C^E9X
} S"mcUU}}
C#;jYBtT7?
s MN*RKer
private void processErrorCode(int nErrorCode) S/ywA9~3Q
{ M]v=-
System.err.println("Error Code : " + nErrorCode); ?rX]x8iP
} cXMhq<GkAA
G.'+-v=\]
\<0B1m
//停止文件下载 y4:H3Sk
public void siteStop() w9RS)l2FQ
{ M@1r:4CoKH
bStop = true; vR6Bn
for(int i=0;i<nStartPos.length;i++) x3ERCqTR
fileSplitterFetch.splitterStop(); 5l-mW0,MK
YNrp}KQ
PYRd]%X
} ^I6^g
} zjL.Bhiud
//负责部分文件的抓取 ^&/G|
**FileSplitterFetch.java SHb(O<6
*/ I:V0Xxz5t
package NetFox; ]&~]#vB#
{4aWR><
}}<Z,/O
import java.io.*; x_!0.SU
import java.net.*; Il@Y|hK
z\ss4
+y2[msBs
public class FileSplitterFetch extends Thread { }{9&:!uA
+|Hioq*,t
U!%!m'
String sURL; //File URL 5Ky#GuC
long nStartPos; //File Snippet Start Position XNMa0
long nEndPos; //File Snippet End Position gkBdR +
int nThreadID; //Thread's ID CRve.e8J
boolean bDownOver = false; //Downing is over HpEQEIvt
boolean bStop = false; //Stop identical 7`IpBm<
FileAccessI fileAccessI = null; //File Access interface yV3^Qtb!
EVX{ 7%
vKwQXR~C
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Z}A%=Z\/3
{ >>Ts??
this.sURL = sURL; Cp`j/rF
this.nStartPos = nStart; MF3b{|Z
this.nEndPos = nEnd; @4(k(
nThreadID = id; gG%V 9eOQ
fileAccessI = new FileAccessI(sName,nStartPos);//定位 '1fNBH2
} (KZHX5T=
dm"n%
[ao U5;7
public void run() depYqYK7G
{ <WXzh5D2
while(nStartPos < nEndPos && !bStop) +(D$9{y
{ "jecsqCgK0
:f5s4N
+QM@VQ
try{ zOEY6lAwI
URL url = new URL(sURL); pu!dqF<
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); e7fiGl
httpConnection.setRequestProperty("User-Agent","NetFox"); 3($"q]Y
String sProperty = "bytes="+nStartPos+"-"; H+}"q$
httpConnection.setRequestProperty("RANGE",sProperty); @UBjq%z
Utility.log(sProperty); wfL-oi'5
8E&XbqP+
uJR%0E7!
InputStream input = httpConnection.getInputStream(); U`Jy!x2m
//logResponseHead(httpConnection); .O*bILU
Ko&hj XHx
!}\4utHY
byte[] b = new byte[1024]; 3bqC\i^[\m
int nRead; m+{K^kr[
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) BYW^/B Y)
{ @''GPL@
nStartPos += fileAccessI.write(b,0,nRead); (\"k&O{
//if(nThreadID == 1) 6ZgU"!|r
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); <D&)OxEn\
} =z?%;4'|
&bqT/H18
8;y&Pb~)
Utility.log("Thread " + nThreadID + " is over!"); rV({4cIe9R
bDownOver = true; f\;65k_jq
//nPos = fileAccessI.write (b,0,nRead); G1t\Q-|l0
} p_ Fy>j
catch(Exception e){e.printStackTrace ();} ]Q "p\@\!
} /MB{Pmk$R
} }~h'FHCC+
IvpcSam'
bsxTqJ
//打印回应的头信息 t:JI!DR
public void logResponseHead(HttpURLConnection con) Iu~\L0R427
{ -IlJ^Al4
for(int i=1;;i++) ;TcvA
{ %xlqF<
String header=con.getHeaderFieldKey(i); v{i7h|e
if(header!=null) =.|J!x
//responseHeaders.put(header,httpConnection.getHeaderField(header)); OI} &m^IOo
Utility.log(header+" : "+con.getHeaderField(header)); 7@.cOB`y@3
else S1_6C:^k
break; qj01]
} H4OhIxK
} ky>wOaTmN6
NVIK>cT6
o ]Jv;Iy@?
public void splitterStop() s{ V*1$e~
{ Q "oI])r
bStop = true; \^1+U JU
} L.xZ_ 6
_<$>*i R
krq/7|
} Z'^U ad6
(nW67YTr
PCd0 ?c
/* KucV3-I
**FileAccess.java /$n ~lf
*//文件访问(定位，写) c[}(OH
package NetFox; C ]Si|D
import java.io.*; 6m.k;'
ES<1tG
,=(Z00#(
public class FileAccessI implements Serializable{ xE}VTHFo'
hA 3HVP_
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 SUWD]k>PH
RandomAccessFile oSavedFile; 6#}93Dgv4
long nPos; L_Q#(in
d;Hn#2C
+^rh[>W
public FileAccessI() throws IOException W$JebW<z(
{ 9 7%0;a8
this("",0); JB</euyV
} BY\:dx)mK
oRN-xng
%CZ-r"A
public FileAccessI(String sName,long nPos) throws IOException }}QTHR
{ G{aT2c
oSavedFile = new RandomAccessFile(sName,"rw"); TUL_TR
this.nPos = nPos; 0Q"u#V Sp
oSavedFile.seek(nPos); @L84>3O
} #6+FY+/
rA0,`}8\
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public synchronized int write(byte[] b,int nStart,int nLen) 6*9}4`
{ h:XzUxL\
int n = -1; 8,?v?uE
try{ Xf=XBoN|
oSavedFile.write(b,nStart,nLen); H-rWDN#
n = nLen; |6J ?8y
} 4@ILw
catch(IOException e) |{g+Y
{ GwsY-jf
e.printStackTrace (); HhA -[p
} |VOg\[f
D+V7hpH-
Mv|ykJoz"
return n; e{({|V '
} @/J[t
He0=-AR8
ufa41$B'yG
} ]"AyAkT(
QVZD/shq
d "BW/%m|g
/* @Un/c:n
**SiteInfoBean.java r#WT`pav
*/ va/m~k|i
package NetFox; HLQ"?OFlz
w&Dv8Wv+Oq
?&WYjTU]H
public class SiteInfoBean { C2]Kc{4
B;Nl~Y|\
^Yr0@pE
private String sSiteURL; //Site's URL TAL/a*7\
private String sFilePath; //Saved File's Path W]<$0
private String sFileName; //Saved File's Name K.tlo^#^B[
private int nSplitter; //Count of Splited Downloading File "Z,q?Fc
J?)RfK|!
|sqZ$Mu
public SiteInfoBean() R~L0{` 0
{//nSplitter的缺省值为5 tc_f;S`k
//default value of nSplitter is 5 5OM?3M
this("","","",5); |6biq8|$3V
} 2.}R
!=Y;h[J.p
CR4rDh8za
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ?tf&pgo
{ 78n}rT%k1
sSiteURL= sURL; 3HG;!D~m;
sFilePath = sPath; y-?>*fNo
sFileName = sName; dYFzye
this.nSplitter = nSpiltter; @$Qof1j'%
mOll5O7VW
fbrp#G71y
} (A k\Lm
,zcQS-e2
lw8"'0
public String getSSiteURL() (J$\-a7<f
{ z^* '@
return sSiteURL; <dA8 '7^
} u%|zc=
\`'KlF2
Qx|H1_6
public void setSSiteURL(String value) `znB7VQ0
{ q)u2Y]
sSiteURL = value; @b&84Gn2 r
} 3K/Df#
ske@uzAz
# jYpVc{]
public String getSFilePath() !Gs} tiMH
{ }`/gX=91
return sFilePath; A)nW
} R U"/2i
V|Tud
]*"s\ix
public void setSFilePath(String value) XY7Qa!>7j
{ Ar9nBJ`
sFilePath = value; /k\01hc`
} }m]q}r
33l>{(y
2H#N{>7
public String getSFileName() H(+<)qH
{ l'4AF| p
return sFileName; "vF MSY
} _68BP)nz>.
:LJ7ru2
U0B2WmT~Q
public void setSFileName(String value) ~m=EM;
{ *}b]rjsj
sFileName = value; uPyVF-i
} jdRq6U^
3&&+YX
bPD)D'Hs
public int getNSplitter() 9 wa,k
{ ]o.vB}WsY
return nSplitter; (ClhbfzD
} V*n==Nb5L
5vp|?-\h>
A;K(J4y*
public void setNSplitter(int nCount) g9tu%cIkR
{ %Tcf6cK"
nSplitter = nCount; -<f/\U
} 0Vv9BL{
} *DeTqO65
HB& &
sLh0&R7
/* Iq'O
**Utility.java ,4F,:w
*/ 9V!-ZG
package NetFox; N{akg90
HQVh+(
0A$SYF$O+[
public class Utility { oN2=DYC41
,\ldz(D?+
CDg AGy
public Utility() 60B-ay0e$b
{ nnCug
6XUuGxQV/
``4wX-y
} *_hLD5K!
WO</Q6+
//线程睡眠 2wpjU&8W!
public static void sleep(int nSecond) W?,$!]0
{ W|c.l{A5Q
try{ OD9 yxN>P
Thread.sleep(nSecond); /0==pLa4
} ~uaP$*B[
catch(Exception e) (i`(>I.(/
{ +cg {[f,J;
e.printStackTrace (); L@)&vn]
} <)#kq1b?
} %]4-{%v
us{nyil1
//日志 hY8#b)l~lu
public static void log(String sMsg) /A(NuB<Pq
{ w+UV"\!G)Q
System.err.println(sMsg); h8}8Lp(/'
} g'lT
8OAg~mQ15(
(!zM\sF
public static void log(int sMsg) Z!\@%`0$
{ xfHyC'?
System.err.println(sMsg); !Tfij(91
} Aka^e\Y@6*
} 1kFjas`g
R_e)mkE
g()m/KS<
/* xPQL?.
**TestMethod.java jXIEp01
*/ bEpMaBN
package NetFox; J/Q|uRpmqr
j7/(sf
"bX4Q4Dq
public class TestMethod { |-kEGLH[*V
jxY-u+B
b7$}JCn
public TestMethod() U6{dI@|B
{ ///xx/weblogic60b2_win.exe 4;<DJ.XlN=
try{ h5onRa*7
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); pMN<p[MB
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); *8\(FVyG^
SiteFileFetch fileFetch = new SiteFileFetch(bean); |~$7X
fileFetch.start(); z+"0>ZN&
} b=LF%P
catch(Exception e){e.printStackTrace ();} <5ZJ]W
c4|so=
:C%47qv
} Dd/}Ya(Gi
\Hum}0[
lO2k<
public static void main(String[] args) zqGYOm$r
{ |=3 *;}
new TestMethod(); Fk$@Yy+}e
} Y><(?
} D@hmO]5c
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