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)); CKw-HgXG
} )\U:e:Zae
for(int i=0;i<nEndPos.length-1;i++) }0~$^J
{ /fQcrd7h
nEndPos = nStartPos[i+1]; e]<Syrk
} .+7n@Sc
nEndPos[nEndPos.length-1] = nFileLength; d%EdvM|)
} DLwlA!z
} 'm0WPS/6E
t/i*.>7
?!ap@)9
//启动子线程 Ust +g4
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 5{ap
for(int i=0;i<nStartPos.length;i++) SiNgV\('U
{ &zn|),
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), h]zok}$
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ~XUUrg;
nStartPos,nEndPos,i); rEr=Mi2
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); % :G78.
fileSplitterFetch.start(); Ehy(;n)\
} TF%n1H-sF
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), c((3B
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); (JU8F-/9
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", (4Db%Iw
nEndPos = " + nFileLength); \^1^|a"
// fileSplitterFetch[nPos.length-1].start(); nS#F*)
oy[s])Tg
M:O*_>KF
//等待子线程结束 +5fB?0D;
//int count = 0; df{?E):
//是否结束while循环 n%r>W^2j
boolean breakWhile = false; lG6&uMvo
lB}?ey
s.(.OXD&
while(!bStop) y9}qB:[bR
{ W *0!Z:?
write_nPos(); 4n#u?)
Utility.sleep(500); H Qj,0#J)
breakWhile = true; m.P F'_)/
]n=z(2Z9lD
?`TQ!m6y
for(int i=0;i<nStartPos.length;i++) II^Rp],>
{ ~U+<JC Z
if(!fileSplitterFetch.bDownOver) h`Jc%6o
{ <mX5VGY9^
breakWhile = false; J rK{MhO
break; dC<%D'L*
} h5{//0 y
} >MJ%6A>
if(breakWhile) hMupQDv/I
break; {F_>cyR
*b;)7lj0h
Tw\@]fw
//count++; HubG>]
//if(count>4) tE>FL
// siteStop(); I N@ ~~
} UXZ3~/L5 O
qX&+
.0nT*LF
System.err.println("文件下载结束！"); `LH9@Z{
} t:dvgRJt*
catch(Exception e){e.printStackTrace ();} QAI=nrlp
} [voc_o7AI
S|d /?}C|e
d%@0xsU1
//获得文件长度 VK4UhN2
public long getFileSize() l="(Hp%b
{ qY&(O`?m&
int nFileLength = -1; [6@bsXiw
try{ Sw$&E
URL url = new URL(siteInfoBean.getSSiteURL()); [1~3\-Y
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); %B&O+~
httpConnection.setRequestProperty("User-Agent","NetFox"); 4FnePi~i
DKo6lP`
qV=O;
int responseCode=httpConnection.getResponseCode(); H94_ae
if(responseCode>=400) OL=X&Vaf<
{ 4JBfA,
processErrorCode(responseCode); oe6Ex5h
return -2; //-2 represent access is error /&?ei*z
} {\?f|mmq
gy1kb,MO
)YCH>Za
String sHeader; r<]^.]3zj
Y&VypZ"G>
~+6#4<M.~
for(int i=1;;i++) C&q}&=3r
{ Uq=Rz8hLM
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); &WCVdZK:
//Utility.log(in.readLine()); b`wT*&
sHeader=httpConnection.getHeaderFieldKey(i); 2!f'l'}
if(sHeader!=null) bil>;&h
{ 0o6r3xc;
if(sHeader.equals("Content-Length")) 5Bcmz'?!
{ `U?S 9m
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); &xj40IZ
break; 4YOLy\"S
} WbFCj0
} <qMX,h2
else NVVAh5R
break; u 'ng'j'
} YC{7;=Pf
} Q2|6WE
catch(IOException e){e.printStackTrace ();} @8YuMD;
catch(Exception e){e.printStackTrace ();} uPFbKSJj
48gpXcc@|
VQ~eg wJL
Utility.log(nFileLength); I%?M9y.u6
1_~'?'&^
7Aw <:
return nFileLength; PVKq&Q?
} N}|1oQkjf
PHsM)V+
NFU=PS$
//保存下载信息（文件指针位置） G4F~V't
private void write_nPos() D-e^b'l
{ 4!glgEE*
try{ z_C7=ga<
output = new DataOutputStream(new FileOutputStream(tmpFile)); d76C]R5L
output.writeInt(nStartPos.length); */]1?M@P)
for(int i=0;i<nStartPos.length;i++) LQ$dT#z2A
{ aBF<it>
// output.writeLong(nPos); OOsd*nX/
output.writeLong(fileSplitterFetch.nStartPos); 3e[k9`
output.writeLong(fileSplitterFetch.nEndPos); (_q&QI0{
} d{^K8T3
output.close(); d[(%5pw~zL
} -mZ{.\9
catch(IOException e){e.printStackTrace ();} Erl@]P4
catch(Exception e){e.printStackTrace ();} or`"{wop
} L'BzefU;04
:Ea]baM"
Z${@;lgP
//读取保存的下载信息（文件指针位置） B@3>_};Ct
private void read_nPos() BW)t2kR&
{ zHj_q%A
try{ KrECAc
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); @0:mP
int nCount = input.readInt(); M+Y^A7
nStartPos = new long[nCount]; Z*5]qh2r8
nEndPos = new long[nCount]; z:$TW{%M
for(int i=0;i<nStartPos.length;i++) P[cGCmM
{ YAF0I%PYU
nStartPos = input.readLong(); V> eJ
nEndPos = input.readLong(); E<_+Tc
} !I8(Y
input.close(); $r)nvf`\
} Y0OVzp9 b
catch(IOException e){e.printStackTrace ();} !91<K{#A{
catch(Exception e){e.printStackTrace ();} ]_)=xF19
} HPWjNwM
VM ny>g&3
XN'X&J
private void processErrorCode(int nErrorCode) qo;F]v*pkK
{ > cJX'U9
System.err.println("Error Code : " + nErrorCode); Sytx9`G 5
} I=`efc]T
|}roR{gc|
jdDcmR
//停止文件下载 M8lR#2n|
public void siteStop() Neb%D8/Kn
{ hta$k%2
bStop = true; +hvVoBCM*
for(int i=0;i<nStartPos.length;i++) ?9H.JR2s%
fileSplitterFetch.splitterStop(); ~Urj:l
yYTiAvN
[+y/qx79
} o;:a6D`
} 7~q'3 N
//负责部分文件的抓取 Z.0^:rVp~
**FileSplitterFetch.java >G+?X+9
*/ *SZ*S%oS3
package NetFox; 6{I5 23g
ZGOI8M]@
7" cgj#
import java.io.*; RT2a:3f
import java.net.*; dQFx]p3L
$}7WJz:
KH&xu,I
public class FileSplitterFetch extends Thread { \oGZM0j
D9&FCCiUE
Ih95&HsdC
String sURL; //File URL c~Hq.K$d
long nStartPos; //File Snippet Start Position _zO,VL
long nEndPos; //File Snippet End Position t UW'E
int nThreadID; //Thread's ID }%rz"kB
boolean bDownOver = false; //Downing is over P8s'e_t
boolean bStop = false; //Stop identical ^Sr`)vP
FileAccessI fileAccessI = null; //File Access interface 0)qLW& w
!$+J7\&7p
dDk<J;~jGJ
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Lp/]iZ@
{ \G*vY#]
this.sURL = sURL; (sn|`k3I
this.nStartPos = nStart; NC2PW+(
this.nEndPos = nEnd; `ml;#n,*
nThreadID = id; O@_)]z?jUc
fileAccessI = new FileAccessI(sName,nStartPos);//定位 sOW-GWSE<
} [H)p#x
\9BIRY`
A! 1>
public void run() }g _#.>D+
{ B)"WG7W E
while(nStartPos < nEndPos && !bStop) ~c3CyOab
{ S*CRVs
Kc\0-3 Z
ziy~~J
try{ W"WvkW>-
URL url = new URL(sURL); )5X7|*LP
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); n/UyMO3=
httpConnection.setRequestProperty("User-Agent","NetFox"); BiHBu8<
String sProperty = "bytes="+nStartPos+"-"; g;bkVq
httpConnection.setRequestProperty("RANGE",sProperty); 4S.%y7d\
Utility.log(sProperty); NzRL(A6V
BZx#@356N
A\.M/)Qo
InputStream input = httpConnection.getInputStream(); M ~!*PCd5
//logResponseHead(httpConnection); (F7!&]8%
J74nAC%J^
rYq8OZLi
byte[] b = new byte[1024]; 4Kt?; y ;
int nRead; QkzPzbF"
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) `&>!a
{ YrgwR
nStartPos += fileAccessI.write(b,0,nRead); O`mW,
//if(nThreadID == 1) KFCzf_P!
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); yZ+o7?(2p
} 5NeEDY2%#
'F[QE9]*
7IZ(3B<87t
Utility.log("Thread " + nThreadID + " is over!"); q^dI!93n|
bDownOver = true; nS'0i&<{1
//nPos = fileAccessI.write (b,0,nRead); w];t]q|
} iygdX2
catch(Exception e){e.printStackTrace ();} 8'#%7+ "=!
} ,)Z^b$H]
} Mi'eViH
'J<KL#og
'L0 2lM
//打印回应的头信息 <v[,A8Q
public void logResponseHead(HttpURLConnection con) y)#Ib*?
{ :d!.E$S
for(int i=1;;i++) J/wot,j^
{ FAU^(]-5m
String header=con.getHeaderFieldKey(i); ;Z.}~d6>!
if(header!=null) F+Lq
//responseHeaders.put(header,httpConnection.getHeaderField(header)); g >-iBxml
Utility.log(header+" : "+con.getHeaderField(header)); |vWx[=`o
else z6FG^
break; Jp5~iC2d
} S`X;2\:
} X'[SCs
T?7ZF+yo6
OjeM#s#N!
public void splitterStop() JYKA@sZHe
{ [>?B`1;@
bStop = true; 'n.eCdj
} 8 s:sMU:Q
Gz~P 0Z^w}
0t*q5pAG".
} %wvSD&oz
/1tqTi
l!q i:H<=1
/* "W:'cIw
**FileAccess.java $o1Gxz
*//文件访问(定位，写) 4"wuqr|o
package NetFox; 8<?60sj
import java.io.*; "PJ@Q9n__
@ZK|k
a*S4rq@
public class FileAccessI implements Serializable{ ZZFa<AK4
W/{HZ<:.
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 +l&ZN\@0X
RandomAccessFile oSavedFile; WZ"x\K-;
long nPos; r#3_F=xL5
m]Z& .,bA
T6-e
public FileAccessI() throws IOException YJXh|@LT
{ |'mgo
this("",0); W)w@ju$Ko
} o& $Fc8bH
{Sd{|R_
[Fr.ik
public FileAccessI(String sName,long nPos) throws IOException LYavth`@h
{ Eh0R0;l5>
oSavedFile = new RandomAccessFile(sName,"rw"); *wyaBV?*K
this.nPos = nPos; J0lTp /
oSavedFile.seek(nPos); =JNoC01D
} )UZ 's>O
NBE)DL
kUn55 l
public synchronized int write(byte[] b,int nStart,int nLen) SH5GW3\h
{ xC!,v 0&
int n = -1; +vBq,'k`
try{ m/%sBw\rx
oSavedFile.write(b,nStart,nLen); hU+sg~E
n = nLen; j$A~3O<e"
} =R?NOWrDY
catch(IOException e) 4 K{4=uU
{ 3(}HD*{E[@
e.printStackTrace (); SG;]Vr
} Nm:nSqc
xAQ=oF +
LYkW2h`JQ
return n; *w59BO&M4
} z9YC9m)jK
Y*B}^!k6
{Qg"1+hhM
} TpuN[Y
@B*?owba>
\BbemCPAm
/* "f(iQI
**SiteInfoBean.java z';p275
*/ D*DCMMp=0
package NetFox; !ZD[ $lt+
n4qj"xQ
.& B_\*
public class SiteInfoBean { %{5mkO&,2
FSIV\ u
d1D{wZ3g
private String sSiteURL; //Site's URL 92bvmP*o4
private String sFilePath; //Saved File's Path 9eH(FB
private String sFileName; //Saved File's Name 6|rqsk
private int nSplitter; //Count of Splited Downloading File 2zh?]if
b,$H!V*
,cYU
public SiteInfoBean() ul>$vUbyf
{//nSplitter的缺省值为5 G?8LYg!-
//default value of nSplitter is 5 8@|+-)t
this("","","",5); [&j!g
} j#9p0[
ShxB!/s
FG38)/
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) %=S~[&8C
{ }rxFX
sSiteURL= sURL; o2@8w[r
sFilePath = sPath; O (<Wn-
sFileName = sName; _}EGk4E
this.nSplitter = nSpiltter; IE+$ET>t
/J<?2T9G
IO/2iSbW
} ABSAle
88$G14aXEk
1K"``EvNB
public String getSSiteURL() Ef;_im
{ ~ 61O
return sSiteURL; ,[D,G
} ^g$k4
=oV8!d%]
c_)vWU
public void setSSiteURL(String value) "gfy6m
{ 6,7Fl=<
sSiteURL = value; /RT3r
} ;m,lS_[c
MP-A^QT
Yi1_oe
public String getSFilePath() @AvXBMq|
{ xYtY}?!"
return sFilePath; {W62%>v
} BBm.;=8@ ^
<fCgU&
t7H2z}06=h
public void setSFilePath(String value) cmmH)6c>
{ @f{yx\u/
sFilePath = value; R)?K+cJ%
} ja$e)
[9u/x%f(
KM*sLC#
public String getSFileName() 4r\Sbh
{ KwlN
return sFileName; ]0GOSh
} aEW Z*y
2[}^ zTtA
9TjAEeU
public void setSFileName(String value) .Kv>*__-Q
{ c (O+s/
sFileName = value; {:$0j|zL1
} ..X efNbl
~Us1F=i_Q
v(3nBZHv_!
public int getNSplitter() yK+76\} I
{ =3?t%l;n
return nSplitter; t48(,
} i,NN"
N'+d1
L[)+J2_<
public void setNSplitter(int nCount) $NJ]2P9L
{ iOm~
nSplitter = nCount; ps[TiW{q;
} 2-ev7:
} c@1C|
8c\mm 0n
L01R.3Z+
/* 5YUn{qtD
**Utility.java #IDDKUE
*/ [3>l^Q|#
package NetFox; 6|r` k75.
: FF:{&d
'm# -)R!
public class Utility { j wlmWO6
;TD<\1HJT=
>V;JI;[
public Utility() lY[>}L*H8
{ HNxJ`x~Z~
`9B xDp]I
_tS<\zy@y
} KOv ar0
, d ?4"8_
//线程睡眠 %4Ylq|d
public static void sleep(int nSecond) @Ytsb!!
{ k ~lj:7g~
try{ oJVpNE[3]
Thread.sleep(nSecond); d}3<nz,
} \K9XG/XIx
catch(Exception e) Nc F
{ PQ.xmg2
e.printStackTrace (); Hq8<g$
} zh2$U dZ|M
} TKvUBy
yc8FEn!)&
//日志 1 h|cr_
public static void log(String sMsg) E)o/C(g
{ %gSqc }v*
System.err.println(sMsg); + 1\1Z@\M
} 4JKB6~Y
Vj_(55WQ
g3 6oEz~|
public static void log(int sMsg) 8Y3c,p/gS>
{ ;Jr6
System.err.println(sMsg); eft-]c+*0
} {H#1wu^]O$
} YiB]}/
Qzw~\KY:
{6^c3R[
/* C_dsYuQ5R
**TestMethod.java ~;_]U[eOL
*/ GeWB"(t
package NetFox; E)3B)(@&P
PvBx<i}A
cEnkt=
public class TestMethod { P5*:r3>
ZZA!Y9ia2
4%LG9hS
public TestMethod() L7_(KCh
{ ///xx/weblogic60b2_win.exe 9*GwW&M%1_
try{ 5Qd |R
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 5)' _3r
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); x=Qy{eIe
SiteFileFetch fileFetch = new SiteFileFetch(bean); \xkLI:*\
fileFetch.start(); V^QKn+/
} ( t#w@<
catch(Exception e){e.printStackTrace ();} 9m0`;~!
N(vzxx^
cR}}NF
} i:Pg&474f
?{?mAbc
7'S/hV%
public static void main(String[] args) W:O<9ZbQ_
{ ~:b bV6YO
new TestMethod(); DQP#h5O
} 2!\y0*}K
} >&TSz5Q
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