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)); 4bE42c=Ca7
} ]bf'
for(int i=0;i<nEndPos.length-1;i++) 4^0\dq
{ xiEcEz'lk
nEndPos = nStartPos[i+1]; . c#90RP
} Oxpo6G
nEndPos[nEndPos.length-1] = nFileLength; 58 kv#;j
} )eVzSj>MT
} zI(xSX@
5[1@`6j
.iN-4"_j1
//启动子线程 vs*>onCf
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; e<kpcF5{\
for(int i=0;i<nStartPos.length;i++) XadG\_?t`
{ .[#xQ=9`
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), LE<:.?<Z-
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ^kc>m$HY
nStartPos,nEndPos,i); -?[O"D"c
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Tq.MubaO
fileSplitterFetch.start(); iOKr9%9?Z
} y/z9Ce*>
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), p!C_:Z5i
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ^*HVP*
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", {`($Q$Q1
nEndPos = " + nFileLength); QziN]
// fileSplitterFetch[nPos.length-1].start(); 'W}~)+zK
g9M')8a n
llHN2R%(
//等待子线程结束 4fZY8
//int count = 0; 8moUK3w
//是否结束while循环 ?0? x+
boolean breakWhile = false; l# }As.o}
:PHUsy
;OQ#@|D
while(!bStop) )Uc$t${en
{ )r-T=
write_nPos(); *xEI Zx
Utility.sleep(500); zuK/(qZ
breakWhile = true; F">Nrj-bs
0~Um^q*'3
+oE7~64LL
for(int i=0;i<nStartPos.length;i++) 5w]DncdQ~
{ &19lk
if(!fileSplitterFetch.bDownOver) L[`R8n1C
{ SJso'6 g
breakWhile = false; )e@01l
break; Z|V"8jE
} C3&17O6
} "bv,I-\
if(breakWhile) EI[e+@J
break; xgZV0!%
SH .9!lQv
Gw{Gt]liq
//count++; Np|:dP9#}
//if(count>4) =>gyc;{2K<
// siteStop(); !%SdTaC{T
} Fr1;)WV
{JCSR2BB
dt`9RB$
System.err.println("文件下载结束！"); jydp4ek_n
} MzBfHt'Rk
catch(Exception e){e.printStackTrace ();} RTdD]pE8Q
} G1`mn$`kq
w`H.ey
[Q2S3szbt6
//获得文件长度 DLwC5Iir
public long getFileSize() <~IH`
{ 0X] ekq
int nFileLength = -1; ?^+#pcX]t|
try{ 4d{"S02h
URL url = new URL(siteInfoBean.getSSiteURL()); x!Z:K5%O
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); F{a0X0ru~
httpConnection.setRequestProperty("User-Agent","NetFox"); S!`4Bl
U89]?^|bb
:F!dTD$
int responseCode=httpConnection.getResponseCode(); 8:3oH!n
if(responseCode>=400) YyQf
{ @lb=-oR!~
processErrorCode(responseCode); pgLzFY['
return -2; //-2 represent access is error 2?#y |/
} M"$jpBN*
pfJVE
3{N p 9y.
String sHeader; <>&e/
J4Q)`Y\~
T U"K#V&u
for(int i=1;;i++) rw}5nv
{ qv ;1$
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); :IP;FrcMP
//Utility.log(in.readLine()); $S($97IU=
sHeader=httpConnection.getHeaderFieldKey(i); ~pX(w!^
if(sHeader!=null) ?~]1Gd
{ .N-'; %8
if(sHeader.equals("Content-Length")) #z-iL!?
{ V7KtbL#
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ]yj4~_&O
break; #Tgz,e9
} (Fbm9(q$d
} } K+Q9<~u
else 7gZVg@
break; {kRDegby
} Skr\a\ J
} 0`g}(}'L
catch(IOException e){e.printStackTrace ();} `JY>v io
catch(Exception e){e.printStackTrace ();} |p=.Gg=2
$v?! 6:
n]6}yJJo
Utility.log(nFileLength); @4 Os?_gJ\
E7Gi6w~\
%>I?'y^
return nFileLength; >[E|p6jgT
} ei|*s+OZu
"c!oOaA
kMJQeo79
//保存下载信息（文件指针位置） (>+k3
private void write_nPos() 5tgILxSK
{ Hb@G*L$
try{ 4$q)e<-
output = new DataOutputStream(new FileOutputStream(tmpFile)); e GqvnNv
output.writeInt(nStartPos.length); '5OVs:)"^
for(int i=0;i<nStartPos.length;i++) lD;,I^Lt6
{ \Z6gXO_
// output.writeLong(nPos); !S >|Qh
output.writeLong(fileSplitterFetch.nStartPos); }jyS\drJ
output.writeLong(fileSplitterFetch.nEndPos); xsY>{/C
} dEAAm=K,<
output.close(); =Nv=Q mO
} +,{Wcb
catch(IOException e){e.printStackTrace ();} 98b9%Z'2f
catch(Exception e){e.printStackTrace ();} vxzf[
} =?`y(k4a
fn?6%q,!ls
CwEWW\Bu
//读取保存的下载信息（文件指针位置） w ;s ]n
private void read_nPos() ]\os`At
{ :>er^\
try{ -UD~>s
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); NZ%~n:/V#
int nCount = input.readInt(); X,JWLS J
nStartPos = new long[nCount]; 0,L$x*Nj5
nEndPos = new long[nCount]; H[_uVv;}6
for(int i=0;i<nStartPos.length;i++) K#6`LL m
{ iEJQ#5))0
nStartPos = input.readLong(); Ei?9M^w
nEndPos = input.readLong(); ^]sMy7X0IK
} )kY_"= d
input.close(); 23u1nU[0
} ffoo^1}1
catch(IOException e){e.printStackTrace ();} 4MF}FS2)
catch(Exception e){e.printStackTrace ();} Q 2SSJ
} n[MIa]dK
jN'fm
t\|K"
private void processErrorCode(int nErrorCode) asmW W8lz
{ abJ@>7V
System.err.println("Error Code : " + nErrorCode); d'x<F[`O
} "e7$q&R |
F)<G]i8n~
h2/1S{/n]
//停止文件下载 (-Ct!aW|
public void siteStop() L9unhx
{ K+\0}qn
bStop = true; ]\9B?W(#
for(int i=0;i<nStartPos.length;i++) 2t`9_zqLw
fileSplitterFetch.splitterStop(); .5[LQR
8a$jO+UvN
c[d'1=Qiy
} m^oi4mV
} jO3u]5}.6
//负责部分文件的抓取 T>uWf#&pjs
**FileSplitterFetch.java VqO<+~M,E
*/ <cfH'~
package NetFox; @<w9fzi
W1vAK
XpAq=p0;
import java.io.*; Z\gg<Q
import java.net.*; \,cKt_{ u
Q3'B$,3O^
1~xn[acy
public class FileSplitterFetch extends Thread { ]x(2}h^S
6L6~IXL>
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String sURL; //File URL U37?P7i's
long nStartPos; //File Snippet Start Position <11Tqb
long nEndPos; //File Snippet End Position ";Ig%]
int nThreadID; //Thread's ID s3E~X
boolean bDownOver = false; //Downing is over 8$jT#\_
boolean bStop = false; //Stop identical n.qxxzEN
FileAccessI fileAccessI = null; //File Access interface Nec(^|[
@Jn:!8U0
QVRokI`BF
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException F+y`4>x
{ G$kwc F'C
this.sURL = sURL; qpwh #^2
this.nStartPos = nStart; !%\To(r[
this.nEndPos = nEnd; RWPdS
nThreadID = id; w3bH|VnU8;
fileAccessI = new FileAccessI(sName,nStartPos);//定位 k| cI!
} QKaj4?p$|S
\/4%[Q2QDm
^Er`{|o6u
public void run() ZO0]+Ko
{ E+c3KqM
while(nStartPos < nEndPos && !bStop) z&vms
{ n]fbV/x
DUliU8B}\
|{LaZXU&
try{ @]"9EW 0
URL url = new URL(sURL); GV@E<dg$R
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); pBnf^Ew1
httpConnection.setRequestProperty("User-Agent","NetFox"); Vh2/Ls5
String sProperty = "bytes="+nStartPos+"-"; l}-`E@w
httpConnection.setRequestProperty("RANGE",sProperty); |QTqa~~B
Utility.log(sProperty); /FV6lR!0^
g2>u]3&W
wJR i;fvi
InputStream input = httpConnection.getInputStream(); %+B-Z/1}
//logResponseHead(httpConnection); m;+1;B
O*/-I pM
GJt9hDM$0
byte[] b = new byte[1024]; 5a|m}2IX
int nRead; 8lGgp&ey
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Wk6&TrWlY
{ 7Z~szD
nStartPos += fileAccessI.write(b,0,nRead); lnSE+YJ>
//if(nThreadID == 1) '*;eFnmvs:
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); aq\TO?
} +siNU#!
8Y~T$Yj^
[%,=0P}
Utility.log("Thread " + nThreadID + " is over!"); PyxN_agf
bDownOver = true; .:!x*v
//nPos = fileAccessI.write (b,0,nRead); -XIvj'u
} y$9t!cx
catch(Exception e){e.printStackTrace ();} dB/I2uGl>
} safS>wM]
} ~I|R}hS
8[`<u[Iv
`[:1!I.}-
//打印回应的头信息 YIUmCx0a
public void logResponseHead(HttpURLConnection con) &Wz:-G7<n
{ +pViHOJu&V
for(int i=1;;i++) (ai-n,y
{ |A/_Qe|s2
String header=con.getHeaderFieldKey(i); PjZvLK@a9)
if(header!=null) J*&=J6
//responseHeaders.put(header,httpConnection.getHeaderField(header)); /~huTKA}
Utility.log(header+" : "+con.getHeaderField(header)); LF.~rmPa
else HtYR 0J
break; 4m!3P"$
} j?hyN@ns
} }e=GvWGa
Pc4cSw#5
1gej$G@
public void splitterStop() J7^T!7V.
{ xQ 3u
bStop = true; U9sub6w6
} '?GZ"C2
@5VZ
uOqDJM'RM
} !Ocg
tU/NwA"
a(T4WDl^
/* }M@Jrq+7
**FileAccess.java 6-}e-H
*//文件访问(定位，写) .V:<w~=b
package NetFox; < ^!eaBR4
import java.io.*; *LdH/C.LIf
pytfsVM
,5uDEXpt{
public class FileAccessI implements Serializable{ ibUPd."W
v$/i5kcWx
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 B_jI!i{N%o
RandomAccessFile oSavedFile; }C`0" 1
long nPos; 8&hn$~ate
{:OVBX
[7w_.(f#
public FileAccessI() throws IOException &YP>"<
{ k\Tm?^L)
this("",0); `9{C/qB
} .h^Ld,Chj
I19F\ L`4
2czL 1Ci
public FileAccessI(String sName,long nPos) throws IOException abP?Dj&
{ N ] /d
oSavedFile = new RandomAccessFile(sName,"rw"); 3"D00~
this.nPos = nPos; >8t[EsW/
oSavedFile.seek(nPos); &`2*6 )qa
} [;8fL
Xb 1^Oj
;K-t
public synchronized int write(byte[] b,int nStart,int nLen) :S6 <v0`Z
{ vJ}
int n = -1; 2DdLqZY#
try{ Cms"OkN
oSavedFile.write(b,nStart,nLen); 8^i,M^f^{
n = nLen; S9055`v5
} )X$n'E
catch(IOException e) ^qr[?ky]&
{ tO3B_zC
e.printStackTrace (); "z4E|s
} yE{UV>ry
UpBYL?+L
RVy87_J1
return n; >&Lu0oHH
} iPNsEQ0We
k rjd:*E
baGI(Dk
} k-0e#"B
o!0a8i
NH6!|T
/* czi!q1<vg
**SiteInfoBean.java <)rH8]V
*/ ?IO/zkeXg
package NetFox; 3_-m>J**
W7>_nK+g?
:Xr3 3
public class SiteInfoBean { 74wa
D)6||z}
RlIqH;n
private String sSiteURL; //Site's URL oC>~r1.j
private String sFilePath; //Saved File's Path 1&nrZG9
private String sFileName; //Saved File's Name * OFT)S
private int nSplitter; //Count of Splited Downloading File o62gLO]z@
wj~8KHan
hV>Ey^Ty
public SiteInfoBean() ^E*C~;^S
{//nSplitter的缺省值为5 )A;<'{t #L
//default value of nSplitter is 5 f89<o#bm7h
this("","","",5); 36UWoo
} Yy1Pipv
||NCVGJG
C.p*mO&N
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) w=2X[V}
{ Hb4rpAeP
sSiteURL= sURL; (b!DJ;(O9
sFilePath = sPath; ePdzQsnVe
sFileName = sName; k Er7,c
this.nSplitter = nSpiltter; gRSG[GMV
4}j}8y2)H
e#{L~3
} 0C_Qp%Z
V^5 t~)#46
Cvy;O~)
public String getSSiteURL() Id1[}B-T
{ /m:}rD
return sSiteURL; 2N#L'v@g=+
} T3Fh7S /
:6{HFMf"
rR;Om1 -,
public void setSSiteURL(String value) Gu=bPQOj
{ ktb.fhO
sSiteURL = value; ${3OQG
} \02e zG
B[h9epU]K
c8MNo'h
public String getSFilePath() G&-h,"yo^
{ :#;?dMkTY
return sFilePath; ) 'KHUa9
} " OtLJ
Dr609(zg^
f}4h}Cq
public void setSFilePath(String value) A}# Mrb
{ -B!pg7>'##
sFilePath = value; rKxk?}
} ,"v%
9X~^w_cdk
2(|V1]6D?
public String getSFileName() I+SL0
{ ;2}Gqh)Yr
return sFileName; 2"T&Fp<
} FSk:J~Z;
AS;{{^mM(
~XRr }z_Lq
public void setSFileName(String value) suwj1qYJ4
{ 7[\B{N9&W
sFileName = value; z=sqO'~
} To+{9"$,
8*ysuL#
Lb/_ULo6-V
public int getNSplitter() ebchHnOd
{ ,58[WZG
return nSplitter; 3z<t#
} tuSgh!
`,O^=HBM
xM,3F jF
public void setNSplitter(int nCount) s zg1.&
{ rO~D{)Nu
nSplitter = nCount; t30V_`eQ
} A(B2XBS!?
} as8<c4:v
2},}R'aR
s_N!6$tS
/* 0=iJT4IEJ
**Utility.java 1/HZY0em
*/ vL7}0n>tz
package NetFox; 5+r#]^eQY-
Tq+pFEgQ`@
wP i=+
public class Utility { |(N4x(xl
%lxo?s@GE
01$SvLn:
public Utility() {*m?t 7
{ K+Qg=vGY
1<F/boF~
=Ev } v
} q b'ka+X
&uM?DQ`o8
//线程睡眠 dxA=gL2
public static void sleep(int nSecond) $f%_ 4 =
{ 03xQ%"TU<
try{ bCsQWsj^NW
Thread.sleep(nSecond); s`{O-
} ]=/f`
catch(Exception e) Hd:ZE::Q'#
{ "6ZatRUd
e.printStackTrace (); .d2s4q\
} CH2o[&
} Msf yIB
zy.Ok 49
//日志 XjC+kH
public static void log(String sMsg) $]9d((u4
{ I'!KWpYJT
System.err.println(sMsg); _%x|,vo`(
} {5*5tCIt
n\QG-?%Pi
i^8Zp;O"f
public static void log(int sMsg) 4-o$OI>
{ @!-= :<h
System.err.println(sMsg); ,^3D"Tky
} 6^p6v
} +um; eL7
82$^pg>
*{ .u\BL5
/* hZy"@y3Yq
**TestMethod.java tY7u\Y;^
*/ 49CMRO,T
package NetFox; sx9N8T3n
iU &V}p
X(8]9
public class TestMethod { 2/GH5b(
tqHXzmsjW
niFjsTA.Z
public TestMethod() 0Y\u,\GrxW
{ ///xx/weblogic60b2_win.exe .w0?
try{ DQ,QyV
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Y$N|p{Z
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); 9:P)@UF
SiteFileFetch fileFetch = new SiteFileFetch(bean); 6ik6JL$AI
fileFetch.start(); 9TeDLp
} 7Kn=[2J5k'
catch(Exception e){e.printStackTrace ();} iVFnt!
E*kS{2NAq
]xuq2MU,l
} @sVBG']p
-V9Cx_]y
v^e[`]u(
public static void main(String[] args) I%%$O'S
{ Z*JZUbo-Q
new TestMethod(); C?zC|0
} (bXCc
} i22R3&C
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