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)); 0Zg%+)iy@
} '}9JCJ
for(int i=0;i<nEndPos.length-1;i++) Lco&Fp
{ Gw1@KKg
nEndPos = nStartPos[i+1]; :Lz\yARpk
} F;>!&[h}G
nEndPos[nEndPos.length-1] = nFileLength; \nP>:5E1
} D$x_o!JT
} gmm.{%1_I;
?^N3&ukkyo
O]m+u
//启动子线程 'g{9@PkGn
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; S<J}[I7V
for(int i=0;i<nStartPos.length;i++) > %KuNy{
{ bAx?&$
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), `HBf&Z
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), OD_W8!-
nStartPos,nEndPos,i); _l1NKk
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); `ta7Gc/:UY
fileSplitterFetch.start(); *Aa?yg:=
} !3ctB3eJ
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Exk\8,EGqS
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); $r3i2N-I
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", F_4n^@M
nEndPos = " + nFileLength); ^k\e8F/
// fileSplitterFetch[nPos.length-1].start(); p l&Muv
]EpWSs!"g
x|5k<CiA
//等待子线程结束 b4pm_Um
//int count = 0; =ha{Ziryo
//是否结束while循环 &:7ZQ1
boolean breakWhile = false; k%G1i-]4
o-Ga3i 8
ZR'H\Z
while(!bStop) vz!s~cAt
{ h3;bxq!q
write_nPos(); RG4sQ0
Utility.sleep(500); /7YF mI/0
breakWhile = true; YSe.t_K2C
9tqF8pb7v
PV=5UyjW
for(int i=0;i<nStartPos.length;i++) Gmz6$^D
{ ?pzaG{
if(!fileSplitterFetch.bDownOver) 5;{H&O9Q
{ @n": w2^B
breakWhile = false; FeTL&$O
break; piZJJYv t
} Zg.&V
} _:VB}>
if(breakWhile) :*2ud(
break; lO_UPC\@fw
%p0xM
a 7,C>%I
//count++; AoI/n4T^
//if(count>4) xoR;=ph
// siteStop(); # m *J&
} :dqn h
LoGVwRmoC
Y(cGk#0
System.err.println("文件下载结束！"); #&7}-"Nd
} 2m2;t0
catch(Exception e){e.printStackTrace ();} =7o"u3hG
} P->y_4O
wg]j+r@
aX}P|l
//获得文件长度 GF^071]G
public long getFileSize() Mwr"~?\\
{ .uk>QMs1
int nFileLength = -1; yT,.z 0
try{ ok4@N @
URL url = new URL(siteInfoBean.getSSiteURL()); 1{r)L{]
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); }7.PH'.8
httpConnection.setRequestProperty("User-Agent","NetFox"); ;y2/-tL?
d:U9pC$
[`):s= FC
int responseCode=httpConnection.getResponseCode(); #gcF"L||
if(responseCode>=400) se>MQM5 )
{ '&|=0TDd+
processErrorCode(responseCode); _Iv6pNd/
return -2; //-2 represent access is error %$Aqle[
} heK7pH7;d
n;T7=1_"
UZpIcj cL
String sHeader; a)'5Nw9*
%&Q$dzgb_
aWY gR
for(int i=1;;i++) !!? Mw
{ BFOq8}fX2
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); jE/AA!DC#
//Utility.log(in.readLine()); GJqJlgHe
sHeader=httpConnection.getHeaderFieldKey(i); :65~[$2
if(sHeader!=null) os]8BScx
{ <"r#:Wr
if(sHeader.equals("Content-Length")) %GS(:]{n
{ #: [<iSk
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); Ch3jxgQY
break; 7F{3*`/6
} 6gs01c,BA
} |]X
else k<\$OoOZ
break; la+[bm<v
} SrK)t.oK
} 8{X"h#
catch(IOException e){e.printStackTrace ();} N/K.%<h
catch(Exception e){e.printStackTrace ();} 9B7^lR
9^G/8<^^>
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Utility.log(nFileLength); S :<Nc{C
gY8>6'~mS
!_cg\KU#
return nFileLength; p$3sME$L
} _ "VkGG
SF<c0bR9
%Va!\#
//保存下载信息（文件指针位置） `.Qi?* ^
private void write_nPos() pxh"B\"4*
{ bq:(u4 3
try{ L=sYLC6d
output = new DataOutputStream(new FileOutputStream(tmpFile)); z3;*Em8Ir
output.writeInt(nStartPos.length); Tap.5jHL
for(int i=0;i<nStartPos.length;i++) h9G RI
{ MfWyc_
// output.writeLong(nPos); (j3xAA
output.writeLong(fileSplitterFetch.nStartPos); YS*9t Q{
output.writeLong(fileSplitterFetch.nEndPos); 65aK2MS@
} !74S
output.close(); W|g4z7Pb
} hj.a&%
catch(IOException e){e.printStackTrace ();} bKN@j'M
catch(Exception e){e.printStackTrace ();} j?x>_#tIY
} +yD`3` E
?}U(3
"\o+v|;
//读取保存的下载信息（文件指针位置） )j0TeE1R
private void read_nPos() In<n&ib
{ 7OJ'){R$
try{ n+A?"`6*#
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); =t H:,SH
int nCount = input.readInt(); WL?\5?G9l
nStartPos = new long[nCount]; U_n9]Z
nEndPos = new long[nCount]; ([m mPyp>L
for(int i=0;i<nStartPos.length;i++) Lja>8m
{ yooX$
nStartPos = input.readLong(); ;CPr]avY
nEndPos = input.readLong(); 2bkX}FWd;
} "C{}Z
input.close(); h_+dT
} vRHd&0
catch(IOException e){e.printStackTrace ();} xk5@d6Y{r
catch(Exception e){e.printStackTrace ();} HV{wI1
} m0;CH/D0
P;ci9vk
+ |#O@k
private void processErrorCode(int nErrorCode) *&^:T~|=!
{ \Ani}qQ%|
System.err.println("Error Code : " + nErrorCode); |m^k_d!d
} G2Qlt@.T
|n,<1QY
iA'lon
//停止文件下载 y+c|vdW%
public void siteStop() {_ i\f ]L
{ Kk-S}.E
bStop = true; G <i@ 5\#
for(int i=0;i<nStartPos.length;i++) iiS-9>]/
fileSplitterFetch.splitterStop(); ]);%wy{Ho
Hn%xDJ'
Vt".%d/`7
} +~mA}psr
} ~l]ve,W[
//负责部分文件的抓取 {pnS Q
**FileSplitterFetch.java 3@M|m<_R$
*/ { + Zd*)M[
package NetFox; Pa V@aM~3
`\#B18eU
`OXpU,Z 6U
import java.io.*; j/f?"VEr
import java.net.*; [d1mLJAR
&h^9}>rVjV
4'a=pnE$
public class FileSplitterFetch extends Thread { p8h9Ng*&`
;;C?{
d9;g]uj`
String sURL; //File URL oPXkYW
long nStartPos; //File Snippet Start Position o:3dfO%nuM
long nEndPos; //File Snippet End Position z8SmkL
int nThreadID; //Thread's ID e%@~MQ-
boolean bDownOver = false; //Downing is over >aj7||K
boolean bStop = false; //Stop identical > dI LF
FileAccessI fileAccessI = null; //File Access interface UQC=g
Vr^n1sgE}r
4{rZppm
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException S||}nJ0
{ ;>?rP88t
this.sURL = sURL; GzI yP(U
this.nStartPos = nStart; {MCi<7j<?
this.nEndPos = nEnd; #xQr<p$L6
nThreadID = id; iS WU'K
fileAccessI = new FileAccessI(sName,nStartPos);//定位 R3;Tk^5A
} CohDO
Rv$[)`&T
&U5{Hm9Ynr
public void run() _m gHJ0v'
{ {B?Wu3-
while(nStartPos < nEndPos && !bStop) !'&n-Q
{ @` 1Ds
*E/`KUG]
{=!b/l;@
try{ QLEKsX7p>
URL url = new URL(sURL); ktFhc3);!
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); k@f g(}6
httpConnection.setRequestProperty("User-Agent","NetFox"); qln3 k`
String sProperty = "bytes="+nStartPos+"-"; p?);eJtV/
httpConnection.setRequestProperty("RANGE",sProperty); beRVD>T
Utility.log(sProperty); r&R B9S@*h
El[)?+;D
+;N2p1ZBf
InputStream input = httpConnection.getInputStream(); %)|9E>fP]N
//logResponseHead(httpConnection); bF"G[pD
%,6#2X nX%
Sa?ksD2IaB
byte[] b = new byte[1024]; g*e
int nRead; #LL?IRH9^
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) _aad=BrMK
{ k.vBj~xU
nStartPos += fileAccessI.write(b,0,nRead); 9F)z4
//if(nThreadID == 1) J'SZ
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); wVicyiY]
} ZUVA EH%
PE}:ybsX
2jg-
Utility.log("Thread " + nThreadID + " is over!"); P@$/P99
bDownOver = true; G7qG$wd8h
//nPos = fileAccessI.write (b,0,nRead); @eD):Y
} tD(7^GuR
catch(Exception e){e.printStackTrace ();} +cgSC5nR
} RrX[|GLSJ
} 2ORNi,_I
\ 3wfwu.q
7\$qFF-y
//打印回应的头信息 x(etb<!jd
public void logResponseHead(HttpURLConnection con) )Dw,q~xgg0
{ 8\^}~s$$A
for(int i=1;;i++) V5sg#|&
{ =j5MFX.-o
String header=con.getHeaderFieldKey(i); -Zf@VW,NI
if(header!=null) ;aI[=?<x
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 6*B19+-
Utility.log(header+" : "+con.getHeaderField(header)); <>s`\ %
else >}`:Ac
break; q3.j"WaP
} `k[-M2[
} Szq/hv=Q
< Z{HX[y
L;VoJf
public void splitterStop() Co (.:z~
{ Q&wB$*u
bStop = true; v(B<Nb
} HJXT9;w
!UG 7Uer
4 N H
} # {w9s0:
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[ oL.+
/* hU`wVy
**FileAccess.java Gn|F`F
*//文件访问(定位，写) 0E,8R{e
package NetFox; 0fF(Z0R,
import java.io.*; Pz>s6 [ob
!c}O5TI|#
'(f&P=[b
public class FileAccessI implements Serializable{ \>jLRb|7Ts
(]0%}$Fo
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 SB1upTn
RandomAccessFile oSavedFile; @.b+av4J
long nPos; ])|d"[ur=
//T>G_1
)PG6gZYW
public FileAccessI() throws IOException T]t+E'sQ
{ A )^`?m3
this("",0); J7=+
} IE;~?W"
_hRcc"MS`
f!oT65Vmi
public FileAccessI(String sName,long nPos) throws IOException p2n0Z\2
{ @hJ%@(
oSavedFile = new RandomAccessFile(sName,"rw"); |]J>R
this.nPos = nPos; l>Z5 uSG
oSavedFile.seek(nPos); "^w]_^GD$d
} 0Sle
q*\x0"mS/
p<TpK )
public synchronized int write(byte[] b,int nStart,int nLen) ?]Pmxp H}
{ CN#+U,NZV
int n = -1; QW$G
try{ oFy=-p+C
oSavedFile.write(b,nStart,nLen); `tHvD=`m.
n = nLen; i`QKH
} |zQ4u
catch(IOException e) P;P%n
{ g .onTFwN
e.printStackTrace (); lJu;O/
} 9z}uc@#D=m
M)eO6oX|
B:gjAb}9T
return n; /4a._@1h[y
} (8Bk;bd
x^kp^ /f
&xa(BX%,c
} .q%WuQw
B8B; y^b>i
b4E:Wn9x
/* lV1G<qP
**SiteInfoBean.java [`^a=:*
*/ ,_Z5m;
package NetFox; ^cczJOxB
\^ZlG.
k 8UO9r[
public class SiteInfoBean { 1u: gFUb
6^]!gR#B
E"+QJ~!
private String sSiteURL; //Site's URL Svondc 4
private String sFilePath; //Saved File's Path LXbP 2
private String sFileName; //Saved File's Name t?}zdI(4
private int nSplitter; //Count of Splited Downloading File Min ^>
ebT:/wu,2
=x<ge_Y
public SiteInfoBean() {DU`[:SQZg
{//nSplitter的缺省值为5 k p<OJy
//default value of nSplitter is 5 3[O=xXB
this("","","",5); pPcTrN'
} |/09<F:L[
x$1]M DAGb
fb{``,nO
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) RLbKD>
{ m=}B,']O
sSiteURL= sURL; :?/cPg'D
sFilePath = sPath; 8-BflejX
sFileName = sName; l-SAC3qhG
this.nSplitter = nSpiltter; &;+-?k|
KVD8YfF
[-\%4
} ^:#D0[
h{AII
OY:,D
public String getSSiteURL() Zn ''_fjh
{ 5[A@gw0u
return sSiteURL; ~ vJ,`?
} W7 Cc
Zy o[(`y
~xD={9BL
public void setSSiteURL(String value) VO$ iNK
{ S<4c r
sSiteURL = value; /% M/
} @^T1XX
_~piZmkG$
nHm}zOLc
public String getSFilePath() MFb9H{LA
{ ;~"FLQg@
return sFilePath; SzjkI+-$:
} p4'G$]#
%@.v2 cT
kg'o&^/=
public void setSFilePath(String value) {vuZ{IJa
{ ;j^H)."A\
sFilePath = value; cUvz2TK
} .ox8*OO<
%d?cP}V
.7l&1C)i
public String getSFileName() *g6n
{ qWODs
return sFileName; Z@3i$8
} ynE)Xdh
kP-3"ACG
7PtN?;rP
public void setSFileName(String value) ^R# E:3e
{ I~ok4L?VB
sFileName = value; zxC#0@qX07
} E;+O($bA
UazP6^{L
|NpP2|4h
public int getNSplitter() Zg'Q>.:
{ XDFx.)t
return nSplitter; ~zJ?H<>
} Ib+Y~ XYR
V+VkY3
4<k9?)~(J
public void setNSplitter(int nCount) /+@p7FqlE
{ }Q=!Y>Tc
nSplitter = nCount; X4 A<[&F/
} q U]gj@R
} kzt(i Y_6
<})2#sZO!
w-Da~[J
/* vTJ}8
**Utility.java %k'!Iq+
*/ c.>oe*+
package NetFox; (=* cK-3
R,pX:H&#+
TrLu~4
public class Utility { U$_xUG
~ xft
>D(RYI
public Utility() +\F'iAs@
{ ,u`B<heoLU
"4uS3h2r
C/TF-g-_Y
} e>(<eu~P
TWQG591
//线程睡眠 f!!V${)X
public static void sleep(int nSecond) X@K-^8
{ P!+'1KR
try{ cm&I* 0\
Thread.sleep(nSecond); J6L K
} DX"xy
catch(Exception e) p2DrEId
{ .ys6"V|31
e.printStackTrace (); %<an9WMF
} D"ND+*Q[X
} b\-&sM(W"
f]JM /
//日志 K }Vv4x1U
public static void log(String sMsg) XqW@rU
{ l}]t~!X=
System.err.println(sMsg); 5[* qi?w=
} _Jme!Oaa
}Rz3<eON
eC[$B99\
public static void log(int sMsg) kH]yl 2
{ fO0XA"=
System.err.println(sMsg); +eFFSt
} y5do1Z
} n~A%q,DmF
x)rM/Kq
{j:hod@-:5
/* W!?7D0q
**TestMethod.java bpKZ3}U
*/ L"{JRbh[
package NetFox; Y6Lf@}2(i
(fCXxyZrr
mo[Zb0>
public class TestMethod { ?sMP~RHQ
6y6<JR-V2k
~:3QBMk::
public TestMethod() DsT>3
{ ///xx/weblogic60b2_win.exe 34d3g
try{ l,,>& F
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ,0hA'cp
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); <-,gAk)u
SiteFileFetch fileFetch = new SiteFileFetch(bean); V??dYB(
fileFetch.start(); u"d~!j1
} AO=h 23ZI
catch(Exception e){e.printStackTrace ();} *T~Ve;3h;
ub;ZtsM,%
$D}{]MN.
} Mi/&f
WnGGo'Z
}jVSlCF@t
public static void main(String[] args) /4vG3
{ :1iqT)&|8F
new TestMethod(); wYQ&C{D%
} tb$LriN
} brdmz}
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