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)); Gcp!"y=i
} "D[/o8Hk
for(int i=0;i<nEndPos.length-1;i++) CoTe$C7
{ |\6Ff/O
nEndPos = nStartPos[i+1]; zwJK|Sk
} NsUP0B}.
nEndPos[nEndPos.length-1] = nFileLength; Lf0Wc'9{
} E`gUNAKQ
} -0:Equ?pz
Eq/oq\(/6
4#Id0['
//启动子线程 gf^XqTLs
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; u~\l~v^mj
for(int i=0;i<nStartPos.length;i++) @; 0t+
{ ~xakz BE
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 1b`WzoJgH
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), M#o'hc
nStartPos,nEndPos,i); :~4M9
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); .xV^%e?H
fileSplitterFetch.start(); 3.E3}Jz`
} fUa[3)I
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 4elA<<
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Jx3fS2
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", o~tL;(sz
nEndPos = " + nFileLength); >Q% FW
// fileSplitterFetch[nPos.length-1].start(); ^Y?Y5`!Q
Ew>lk9La(
$4u8"ne)
//等待子线程结束 =+"=|cQ
//int count = 0; K3-Cuku
//是否结束while循环 AroYDR,3+
boolean breakWhile = false; |Wz`#<t
*e%(J$t
Gf\u%S!%
while(!bStop) X(dHhO
{ 6 TSC7jO
write_nPos(); +_v#V9?
Utility.sleep(500); qJq!0F
breakWhile = true; <EM'|IR?
2{I+H'w8:
rUWC=?Q
for(int i=0;i<nStartPos.length;i++) ^<w3i?KPW
{ 'Z82+uU%
if(!fileSplitterFetch.bDownOver) Vk?US&1q}
{ IZ3e:
breakWhile = false; zelM}/d
break; *Vr;rk
} ) ={ H
} +~f5dJyk`
if(breakWhile) 1YJ@9*l
break; E)]RQ~jY?
>@uFye$
1,Ji|&Pwf
//count++; ,;~@t:!c
//if(count>4) E%vT(Kz
// siteStop(); IW5N^J
} Dx>~^ ^<
*28:|blbL
2'5u}G9
System.err.println("文件下载结束！"); +?bjP6w_g
} z,IUCNgM
catch(Exception e){e.printStackTrace ();} WNWtQ2]
} &LDA=B
&7Lg)PG
|tdsg
//获得文件长度 H#FH'@J
public long getFileSize() "HrZv+{
{ .qD=u1{p9
int nFileLength = -1; xay~fD
try{ Ae|bAyAK
URL url = new URL(siteInfoBean.getSSiteURL()); j,CVkA*DY
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); K~Z$NS^W&
httpConnection.setRequestProperty("User-Agent","NetFox"); ;b;Bl:%?
*@zya9y9q
X-}]?OOs
int responseCode=httpConnection.getResponseCode(); ],xvhfZ"dn
if(responseCode>=400) 53O}`xX!6
{ .kZ<Q]Vk
processErrorCode(responseCode); -PLh|
return -2; //-2 represent access is error I6RF;m:Jw
} tde&w=ec
Yrmd hSY
PIZK*Lop
String sHeader; eg(1kDMpn
<jIuVX
23*OuY
for(int i=1;;i++) NkY7Hg0
{ 3R6=C~
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); I|R;)[;X
//Utility.log(in.readLine()); (Qj;B)
sHeader=httpConnection.getHeaderFieldKey(i); 4d;.p1ro
if(sHeader!=null) }^]TUe@a
{ pfF2!`7pI
if(sHeader.equals("Content-Length")) t2RL|$>F1
{ hd~0qK
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ~Zo;LSI
break; @JU Xp
} %WAaoR&u
} H rI(uZ]
else lCiRvh1K
break; 5"2pU{xmK
} '-M9v3itC
} ]y~"M
catch(IOException e){e.printStackTrace ();} H.#zbKj
catch(Exception e){e.printStackTrace ();} !A'3Mw\Nm
U_<k*o@:
Wz)@k2
Utility.log(nFileLength); {I]>!V0j!
2"8qtG`Et
` 3h,Cy^
return nFileLength; Z@6xu;O
} E<r<ObeRv`
;>r E+k%_
p}(pIoyUF
//保存下载信息（文件指针位置） BT*{&'\/
private void write_nPos() VJOB+CKE
{ Y20T$5{#
try{ }-T :
output = new DataOutputStream(new FileOutputStream(tmpFile)); CC|=$(PgT
output.writeInt(nStartPos.length); (\M+E tU<9
for(int i=0;i<nStartPos.length;i++) HL~DIC%
{ eoxEnCU
// output.writeLong(nPos); Uj twOv|pF
output.writeLong(fileSplitterFetch.nStartPos); dr^MW?{a\
output.writeLong(fileSplitterFetch.nEndPos); QW= X#yrDO
} p"d_+
output.close(); h4N&Ybfo
} ~en'E
catch(IOException e){e.printStackTrace ();} |^C35 6M>
catch(Exception e){e.printStackTrace ();} jYE ?wc+FT
} -I.BQ
@H61^K<
\JBPZ~N3
//读取保存的下载信息（文件指针位置） "P8(R
private void read_nPos() OTD<3Q q
{ #y*p7~|@
try{ $mcq/W
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); (gjCm0#_%
int nCount = input.readInt(); h1Logm+m
nStartPos = new long[nCount]; uy8mhB+]
nEndPos = new long[nCount]; !m6=Us
for(int i=0;i<nStartPos.length;i++) FC#t}4as
{ ?9ScKN
nStartPos = input.readLong(); F`M`c%
nEndPos = input.readLong(); qv)%)n
} g [c^7
input.close(); |C}= 1
} 8RjFp2)W
catch(IOException e){e.printStackTrace ();} wPl9%
catch(Exception e){e.printStackTrace ();} Tno 0Q +
} *nlDN4Y[
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private void processErrorCode(int nErrorCode) "HtaJVp//
{ .wf$]oQQ
System.err.println("Error Code : " + nErrorCode); =&#t("
} C(&3L[
tb;u%{S
51Q~/
//停止文件下载 vBYk"a6SD
public void siteStop() g]jCR*]
{ g<^-[w4/
bStop = true; G!E1N(%o
for(int i=0;i<nStartPos.length;i++) FZx.Yuv
fileSplitterFetch.splitterStop(); q" @%WK
T0"q,lrdxV
,"?xy-6
} |Fe*t
} Huf;A1.
//负责部分文件的抓取 F5%IsAH
**FileSplitterFetch.java AYv7-!Yk
*/ n7pjj
package NetFox; C~R,,
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import java.io.*; ca,U>'(y
import java.net.*; S3gd'Bahq
1;JH0~403
jS4fANG
public class FileSplitterFetch extends Thread { WP >VQZ&
L16">,5
vQmqYyOc2
String sURL; //File URL }xpo@(e
long nStartPos; //File Snippet Start Position Ti$_V_
long nEndPos; //File Snippet End Position |vgYi
int nThreadID; //Thread's ID Zb$P`~(%
boolean bDownOver = false; //Downing is over U(5Yg
boolean bStop = false; //Stop identical 4q*mEV
FileAccessI fileAccessI = null; //File Access interface I\@`AU
{QVs[ J1
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException =`.OKUAn
{ wW|[Im&
this.sURL = sURL; Xd5uF/w
this.nStartPos = nStart; M`H@ % M
this.nEndPos = nEnd; hE;BT>_dn
nThreadID = id; zR5KC!xc
fileAccessI = new FileAccessI(sName,nStartPos);//定位 3 uJ?;
} 91M5F$
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public void run() tf6 Zz[
{ =6gi4!hE
while(nStartPos < nEndPos && !bStop) B~2M/&rM\
{ 'Xu3]'m*
j.+}Z |
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try{ DeTLh($\
URL url = new URL(sURL); G<Y}QhFU
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); yny1i9 y
httpConnection.setRequestProperty("User-Agent","NetFox"); {9-n3j}
String sProperty = "bytes="+nStartPos+"-"; *{dMo,.eI
httpConnection.setRequestProperty("RANGE",sProperty); C=`MzZbJ
Utility.log(sProperty); t(p}0}Pp
V z-]H]MW,
`NCH^)
InputStream input = httpConnection.getInputStream(); -ju}I
//logResponseHead(httpConnection); i=jYl
@.} @K
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byte[] b = new byte[1024]; t^"8 v3'h
int nRead; J*t_r-z
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) mZ~f?{
{ Z+2 j(
nStartPos += fileAccessI.write(b,0,nRead); 1!Afq}|
//if(nThreadID == 1) "mc ]^O
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Or:P*l
} }A&I@2d
%PC8}++
@bZ,)R
Utility.log("Thread " + nThreadID + " is over!"); @k)[p+)E
bDownOver = true; YRu#JYti
//nPos = fileAccessI.write (b,0,nRead); ,&G!9}EC
} Lm*PHG
catch(Exception e){e.printStackTrace ();} 0A')zKik
} .1jeD.l
} , FR/X/8
"x O+
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//打印回应的头信息 wicW9^ik
public void logResponseHead(HttpURLConnection con) dZCnQIS
{ v(=E R%
for(int i=1;;i++) $8`"
{ SE6c3
String header=con.getHeaderFieldKey(i); 7KN+ @6!x
if(header!=null) ^/~C\ (
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ;),vUu,k
Utility.log(header+" : "+con.getHeaderField(header)); GQDW}b8
else A+hA'0isF@
break; d fSj= 4
} 1u~a*lO}
} 5em*9Ko
j7~Rw"(XQc
}z5u^_-m
public void splitterStop() ~W-5-Nl{s
{ 5 Q/yPQN
bStop = true; rUZ09>nDy
} +h8`8k'}-2
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BbhC0q"J
} .yB{+
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C(kL=WD
/* cVli^*se
**FileAccess.java avW33owb@
*//文件访问(定位，写) {xf00/
package NetFox; Q^):tO]!Ma
import java.io.*; NRazI_Z
(Ta(Y=!uq
W0<2*7s
public class FileAccessI implements Serializable{ vURgR
Xn02p,,
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 pO)5NbU
RandomAccessFile oSavedFile; kAq#cLprG
long nPos; 77-G*PI*I
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public FileAccessI() throws IOException N v6=[_D
{ qWD(rq+9
this("",0); O bc>f|l]
} u}89v1._Jn
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m .R**g
public FileAccessI(String sName,long nPos) throws IOException f$qkb$?]}
{ }6gum
oSavedFile = new RandomAccessFile(sName,"rw"); I.it4~]H
this.nPos = nPos; 1rON8=E
oSavedFile.seek(nPos); rTqGtmulG
} z fu)X!t^
73JrK_h
b4Pa5w
public synchronized int write(byte[] b,int nStart,int nLen) #3?}MC
{ D#gC-,
int n = -1; =yWdtBng
try{ +G)a+r'0Q
oSavedFile.write(b,nStart,nLen); ^Hz1z_[X@
n = nLen; lN x7$z`
} Y|buQQ|
catch(IOException e) A=wG};%_
{ )r?-_qj=
e.printStackTrace (); k; >Vh'=X
} D4sp+
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7"1]5\p^g
return n; ~_ u3_d.
} \2CEEs'
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R?M>uaxn
} L_o/fTz4
=MT'e,T
'$[%x
/* =|dHD
**SiteInfoBean.java V>D}z8w7
*/ U+zntB
package NetFox; V[n,fEPBr
ja6V*CWb
%M:$ML6b<
public class SiteInfoBean { fk!9` p'
zbgGK7
]E6r)C
private String sSiteURL; //Site's URL x"r,l/gzy
private String sFilePath; //Saved File's Path =}YX I
private String sFileName; //Saved File's Name wNU;gz
private int nSplitter; //Count of Splited Downloading File .A0fI";Q
$hMD6<e
Qe-PW9C
public SiteInfoBean() <W+9h0c
{//nSplitter的缺省值为5 AH_qZTv0{Q
//default value of nSplitter is 5 "BZ@m:I6hy
this("","","",5); 3O;"{E= <
} }Rw6+;
X4{<{D`0t8
"Q{l])N
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) | AiMx2
{ t7Mq>rFB
sSiteURL= sURL; JKy~'>Q
sFilePath = sPath; )?pnV":2Y
sFileName = sName; UmY{2 nzY
this.nSplitter = nSpiltter; q@tym5
_07$TC1
LR';cR;
} #jd.i
|(AFU3~
O<E8,MCA[a
public String getSSiteURL() %k~ezn
{ Dt{WRe\#
return sSiteURL; (L yKo
} K)5j
aNA]hl
,HI%ym
public void setSSiteURL(String value) q^?a|l
{ Qqx!'fft
sSiteURL = value; Cy*.pzCi
} [P6m8%Y|s
kdp^{zW}
#Ge_3^'
public String getSFilePath() i,S1|R
{ sN2m?`?"G
return sFilePath; `- (<Q;iO
} WIuYSt)h
g[bu9i
]^T-X/v9
public void setSFilePath(String value) `oH4"9&]k3
{ SN]g4}K-
sFilePath = value; Ln t 1
} lRNm &3:-
iQS,@6
Js vdC]+
public String getSFileName() `( w"{8laB
{ _ Yc"{d3S
return sFileName; j9l32<h7]
} 3 ^K#\*P
Ga-cto1Y
cpALs1j:
public void setSFileName(String value) ch25A<O<R.
{ #9Ect@?N0
sFileName = value; V1pBKr)v
} `*BV@
6q>}M
&9|L Z9K
public int getNSplitter() :`Ut.E~.
{ ,.}%\GhY
return nSplitter; 6`20
} 9 M%Gnz
nO!&;E&
RV);^, b
public void setNSplitter(int nCount) ar6+n^pi0]
{ |cgjn*a?M
nSplitter = nCount; UoKVl-
} tfZ@4%'
} qw?(^uZNW
(CY D]n
+:4>4=
/* 3ce$eZE
**Utility.java =QGmJ3
*/ x^EW'-a
package NetFox; NkO+)=
m#Z&05^
;+(VO
public class Utility { {Dk!<w I)
d;]mwLB0
E #B$.K
public Utility() J-<_e??
{ /I!62?)-*
3Ovx)qKxd
,[zSz8R
} ;Q^>F6+_m
WZY+c
//线程睡眠 (RV#piM
public static void sleep(int nSecond) >}%#s`3W1_
{ AvB=/p@]
try{ bxtH`^
Thread.sleep(nSecond); r)>3YM5
} v_Sa0}K9
catch(Exception e) ",D!8>=s
{ DXI4DM"15I
e.printStackTrace (); 8FMxn{k2
} EJ#I7_
} q,O_y<uw
KFwuz()7
//日志 yxHo0U
public static void log(String sMsg) ,?erAI
{ -grmmE]/
System.err.println(sMsg); Qn.dL@W
} &1yJrj9y
0NGth(2
z k/`Uz
public static void log(int sMsg) 6PYt>r&TO
{ W"\}##
System.err.println(sMsg); 6j XDLI
} 'z AvQm
} =eUKpYI
GdI,&|/
ye9GBAj /
/* 2[ofz}k]r)
**TestMethod.java %UrNPk
*/ I`X!M!dB)
package NetFox; [`b,SX x
]tN)HRk1
N6"sXwm
public class TestMethod { rzIWQFv
@Kz,TP!%A
">CRFee0
public TestMethod() eyJWFJh
{ ///xx/weblogic60b2_win.exe gv>DOez/
try{ jVd`J
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); "Gp Tmu?
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); w01[oU$x=
SiteFileFetch fileFetch = new SiteFileFetch(bean); z+7V}aPM
fileFetch.start(); bE.<vF&
} 4@3\Ihv
catch(Exception e){e.printStackTrace ();} c-(RjQ~M5
N,-C+r5}<4
&gY578tU
} K~,!IU_QG
J<"K`|F
5>.ATfAsV
public static void main(String[] args) Ie/_gz^
{ <<u]WsW{C
new TestMethod(); (m:Q'4Ep
} ) hs&?:)
} \tYImh
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