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)); $X<O\Kna
} l*~O;do
for(int i=0;i<nEndPos.length-1;i++) ?!TFoD2'
{ {~q"Y]?
nEndPos = nStartPos[i+1]; `u6CuH5
} MIma:N_c
nEndPos[nEndPos.length-1] = nFileLength; UtPFkase
} nX%b@cOXj
} .UX`@Q:Gp
=f0qih5.4
C'$w*^me
//启动子线程 nMm4fns
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 35=kZXwG+4
for(int i=0;i<nStartPos.length;i++) -i93
{ (:Di/{i&r5
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Rr#Zcs!G
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ZD!?mR+-
nStartPos,nEndPos,i); q_iPWmf p*
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); X)7_@,7
fileSplitterFetch.start(); kq|(t{@Rp
} :Ywb
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 8LuM eGs
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); >}<1
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 3{c6)vR2
nEndPos = " + nFileLength); =D-u".{
// fileSplitterFetch[nPos.length-1].start(); R 6JHRd
iB4`w\-o
D2}N6i
//等待子线程结束 wNc.z*+O"H
//int count = 0; M;2@<,rM
//是否结束while循环 |)~t^
boolean breakWhile = false; eka<mq|W
-)N,HAM>
>^Rkk{cc
while(!bStop) r~rftw
{ RvQa&r5l
write_nPos(); 709/'#- ^
Utility.sleep(500); Yzr)UJl*I
breakWhile = true; EKu%I~eM
/=5:@
|k.%e4
for(int i=0;i<nStartPos.length;i++) }ejZk bP
{ CghlyT
if(!fileSplitterFetch.bDownOver) \-?0ab3Z
{ N!~O~Eo3
breakWhile = false; zSd!n
break; Ww=^P{q\
} Gxhr0'
} _v6x3 Z
if(breakWhile) LX'z7fh
break; m&MAA^I
jouA ]E
&&PXWR!%]
//count++; lcVZ 32MQ
//if(count>4) px${ "K<
// siteStop(); .9NYa|+0
} n2A ; `=
iW%~>`tT
i(qZ#oN
System.err.println("文件下载结束！"); NHaY&\
} G)8v~=Bv
catch(Exception e){e.printStackTrace ();} '3|fv{I
} { )g $
S(^HIJK
s$gR;su)g
//获得文件长度 Xb<>AzEM
public long getFileSize() !i>d04u`%
{ ]\Z8MxFD
int nFileLength = -1; Lv&9s
try{ 'fjouO
URL url = new URL(siteInfoBean.getSSiteURL()); [s{ B vn
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !!k^M"e2
httpConnection.setRequestProperty("User-Agent","NetFox"); p>N8g#G
[$X^r<|P@
H\fsyxM7
int responseCode=httpConnection.getResponseCode(); +'|nsIx,
if(responseCode>=400) Sx8RH),k
{ @{>0v"@
processErrorCode(responseCode); pC~M5(F_
return -2; //-2 represent access is error -e4TqzRr
} 1*GL;W~ix*
fc&djd`FuX
Xj9\:M-
String sHeader; a[_IG-l|i4
${)oi:K@:
uG$*DeZti
for(int i=1;;i++) 4mHk,Dd9,
{ $\+x7"pI
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); uv=a}U;
//Utility.log(in.readLine()); \Up~"q>Kb
sHeader=httpConnection.getHeaderFieldKey(i); >[2;
if(sHeader!=null) jiejs*
{ S6g_$Q7
if(sHeader.equals("Content-Length")) h! Bg}B~
{ eDsB.^|l
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 9:E:3%%
break; xtBu]I)%
} ?W>`skQ
} @<.ei)cqb
else L} "bp
break; @>,GCuPrm
} VOJ/I Dl 4
} #;[0:jU0
catch(IOException e){e.printStackTrace ();} s:k?-u@
catch(Exception e){e.printStackTrace ();} Lb?WhjqZ
;}Ei #T,D
!r8_'K5R(
Utility.log(nFileLength); bvOnS0,y
k!ID
%8H$62w]
return nFileLength; uPq@6,+
} I7wR[&L885
[Tl66Eyl
DRpFEWsm
//保存下载信息（文件指针位置） mW$Oi++'d
private void write_nPos() :R`e<g~4
{ x6)qs-
try{ H:|.e)$i
output = new DataOutputStream(new FileOutputStream(tmpFile)); k`;d_eW
output.writeInt(nStartPos.length); * RyU*au
for(int i=0;i<nStartPos.length;i++) +_L]d6
{ iZLy#5(St
// output.writeLong(nPos); A=0{}B#
output.writeLong(fileSplitterFetch.nStartPos); Y7zs)W8xTT
output.writeLong(fileSplitterFetch.nEndPos); l$Vy\CfK3n
} A%2B3@1'q
output.close(); HC}vO0X4
} =;4K5l{c
catch(IOException e){e.printStackTrace ();} 1c{m rsB
catch(Exception e){e.printStackTrace ();} }N}Js*
} p+8o'dl8=
IG{lr
:%z#s
//读取保存的下载信息（文件指针位置） zYP6m3n
private void read_nPos() }SC&6B?G
{ 6J\ 2=c`
try{ }L(ZLt8Q
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); \WBO(,]V
int nCount = input.readInt(); Y=4 7se=h"
nStartPos = new long[nCount]; tz8fZ*n
nEndPos = new long[nCount]; 8k3y"239t
for(int i=0;i<nStartPos.length;i++) Wsgp#W+
{ q 'd]
nStartPos = input.readLong(); ]ag{sU@#
nEndPos = input.readLong(); |{Ex)hkw
} x|yJCs>
input.close(); EjFn\|VK
} }`2a>N: &
catch(IOException e){e.printStackTrace ();} Z;V(YK(WO.
catch(Exception e){e.printStackTrace ();} eKy!Pai
} w\MWr+4
O_qwD6s-_
t V( WhP
private void processErrorCode(int nErrorCode) O\ _ro.
{ >|c?ZqW
System.err.println("Error Code : " + nErrorCode); \gA<yz-;N
} 0zA;%oP
ilde<!?
n 7i5A:
//停止文件下载 0TaI"/ai
public void siteStop() ;<q2
{ n807?FORB
bStop = true; IIih9I`IR
for(int i=0;i<nStartPos.length;i++) KJV8y"^=Q
fileSplitterFetch.splitterStop(); tT!'qL.*
[|ZFei)r
yuy\T(7BN
} !(7m/R
} kc0MQ TJU
//负责部分文件的抓取 Pn^`_
**FileSplitterFetch.java nShXY6bA
*/ pbEWnx_
package NetFox; _}Qtx/Cg
>O<a9wz
QRvyaV
import java.io.*; 6`7tTn?n
import java.net.*; #2s}s<Sc;
@"`}%-b
c+&Kq.~K
public class FileSplitterFetch extends Thread { 9DJ&J{2W
zt: !hM/Vt
S9Oz5_x
String sURL; //File URL Dm{Xd+Y
long nStartPos; //File Snippet Start Position nhdZC@~E0
long nEndPos; //File Snippet End Position -N% V5 TN
int nThreadID; //Thread's ID hcj]T?
boolean bDownOver = false; //Downing is over ]:#=[CH
boolean bStop = false; //Stop identical J/jkb3
FileAccessI fileAccessI = null; //File Access interface \?]U*)B.r
)2RRa^=&
cz,QP'g
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException C 2nmSXV
{ {j9TzR
this.sURL = sURL; rbnAC*y8'L
this.nStartPos = nStart; QK?V^E
this.nEndPos = nEnd; s2"`j-iQ
nThreadID = id; t 86w&
fileAccessI = new FileAccessI(sName,nStartPos);//定位 >vp4R`
} BK%.wi
)M.s<Y
sBB[u'h!
public void run() ?tY+P`S
{ cFw-JM<
while(nStartPos < nEndPos && !bStop) A[uE#T^
{ )I[f(f%W7
`v!. ,Yr
8 7(t<3V&
try{ {7jim
URL url = new URL(sURL); A!Cby!,
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !Pw*p*z
httpConnection.setRequestProperty("User-Agent","NetFox"); |J,zU6t
String sProperty = "bytes="+nStartPos+"-"; aSvv(iV
httpConnection.setRequestProperty("RANGE",sProperty); . 2$J-<O
Utility.log(sProperty); 5PO_qr=Hx
JyZuj>` 6
*0xL(
InputStream input = httpConnection.getInputStream(); Vt(Wy
//logResponseHead(httpConnection); F|eWHw?t
'KA$^
4?1Qe\A^
byte[] b = new byte[1024]; ?VNtT/
int nRead; f~T7?D0u}N
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) V.&F%(L
{ e?.j8Q~
nStartPos += fileAccessI.write(b,0,nRead); X#ttDB
//if(nThreadID == 1) 3T8d?%.l
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); >lV,K1Z
} salC4z3
+#MXeUX"
O3@DU#N&s
Utility.log("Thread " + nThreadID + " is over!"); uVUU1@
bDownOver = true; vSR&>Q%X
//nPos = fileAccessI.write (b,0,nRead); ;:D-}t;
} ;.uYWP|9
catch(Exception e){e.printStackTrace ();} ?OFa Q
} 3/`BK{
} (p{%]M
).;{'8Q
i"}z9Ae~.
//打印回应的头信息 n7fhc*}:`
public void logResponseHead(HttpURLConnection con) !CUl1L1DSi
{ 8{jXSCP#
for(int i=1;;i++) dhtH&:J<;
{ Q4m> 3I
String header=con.getHeaderFieldKey(i); 4j=3'Z|
if(header!=null) UE'=9{o`
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ?9()ya-TE
Utility.log(header+" : "+con.getHeaderField(header)); UON=7}=$&
else = g{I`u
break; %PYO9:n
} $_"u2"p
} t`z"=S
j**[[
vHf)gi}O|
public void splitterStop() 6^gp /{
{ #"4ioTL2
bStop = true; -5b|nQuY
} =@Oo3*>
\:4*h
)k=KLQ\b
} :')[pO_FW*
]gq)%T]
oh8:1E,I
/* @e)}#kN.
**FileAccess.java f256;3n
*//文件访问(定位，写) X%'z
package NetFox; "@&TC"YG0
import java.io.*; W^[FWFUTY
]?4;Lw
Q-w# !<L.
public class FileAccessI implements Serializable{ tLy:F*1i
^xa, r#N:V
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 @q'kKVJs
RandomAccessFile oSavedFile; syR"p,3EC
long nPos; RE;A0E_3
"#iJ/vy
}*6BaB
public FileAccessI() throws IOException =IC.FT}
{ mITB\,,G
this("",0); op}!1y$9P
} o^@"eG$,
'GJB9i+a^
[h3xW
public FileAccessI(String sName,long nPos) throws IOException h9Far8}
{ "r&,#$6W6
oSavedFile = new RandomAccessFile(sName,"rw"); P$obID
this.nPos = nPos; cX-M9Cz
oSavedFile.seek(nPos); N]+6<
} Q~(Gll;
bgorW"'
&'z_:Wm
public synchronized int write(byte[] b,int nStart,int nLen) 7'IIB1v.\
{ V\Cl""`XN
int n = -1; Y*c]C;%=
try{ 2l)"I
oSavedFile.write(b,nStart,nLen); $.jGO!
n = nLen; dTg`z,^F
} ?Zb+xNKJ(
catch(IOException e) 3NpB1lgh&:
{ q}P@}TE
e.printStackTrace (); %l7[eZ{Y
} J9mK9{#q
<T_3s\
bTD?uX!^@
return n; cT'Bp)a
} XGSFG~d
4EqThvI{
}93kHO{
} Cb;6yE)!Z
AY/.vyS
;R*-cm
/* jaoZ}}V_$
**SiteInfoBean.java [Fr](&Tx
*/ /w?e(v<
package NetFox; KOy{?
lMY\8eobcB
*?X&Y8Kf
public class SiteInfoBean { u<S`"MR:J
#%E`~&[
*E/Bfp1LIe
private String sSiteURL; //Site's URL [9">}l
private String sFilePath; //Saved File's Path LIID(s!bX
private String sFileName; //Saved File's Name >G5aFk
private int nSplitter; //Count of Splited Downloading File yvB]rz} i
yzS^8,
=d{6=2Pt
public SiteInfoBean() 4zMvHe
{//nSplitter的缺省值为5 Ms!EK
//default value of nSplitter is 5 ws0qwv#
this("","","",5); ?6:qAFw
} sq'm)g
kOQ)QX
k+h}HCzE
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ztO)~uL
{ U<j5s\Y,
sSiteURL= sURL; lCU clD
sFilePath = sPath; & &}_[{fc
sFileName = sName; P)Adb~r
this.nSplitter = nSpiltter; h[remR#3\
PF~@@j
kk=n&M
} _EMI%P&s
gQ\.|'%
GeR#B;{
public String getSSiteURL() ?Q]&;5o
{ GY$Rkg6d
return sSiteURL; .RxTz9(
} ,t`V^(PEq
vvxxwZa=O
0>|q[SC
public void setSSiteURL(String value) ^EUR#~b5iy
{ MLdwf}[
sSiteURL = value; 2b$>1O&2
} V8n {k'
,XT,t[w
X?_rD'3
public String getSFilePath() WzzA:X
{ ew1L+
return sFilePath; e/D{^*~S
} <,~OcJG(
hV7EjQp
| 1B0
public void setSFilePath(String value) #*.!J zOg
{ ^OY$ W
sFilePath = value; &hWELZe0vv
} b-&rMML
iE'_x$i
lju5+0BSb
public String getSFileName() 8&@=Anc&q
{ m^ xTV-#l@
return sFileName; e)e(f"t6Q
} qR@ESJ_
TZgtu+&
E^-c,4'F
public void setSFileName(String value) "uBnK!
{ \tgY2:
sFileName = value; +p\E%<uQ
} ;?Pz0,{h
1n`[D&?q
? $B4'wc5
public int getNSplitter() Km5_P##
{ Gld~GyB\k
return nSplitter; \n_7+[=E
} q2%cLbI F
{-5)nS^_
$1])>m_ct
public void setNSplitter(int nCount) u#ya 8
{ gT8(LDJ
nSplitter = nCount; MD[hqshoh
} F8w7N$/V",
} {7e(0QK
Q`bXsH
5p.rd0T]l3
/* )?72 +X
**Utility.java eCI'<^
*/ t!\aDkxo %
package NetFox; w[z=x
C@qWour
EE'2<"M
public class Utility { #4AU&UM+i
:j]6vp6
,ojJ;w5D
public Utility() ]G["TX,
{ 5RLO}Vn]
Szzj9K
[4yHXZxza
} Be{@ L
Pim
//线程睡眠 j([b)k=
public static void sleep(int nSecond) gV]4R"/
{ IgbuMEfL
try{ 'fn}I0Vc
Thread.sleep(nSecond); [],[LkS
} EeYL~ORdi
catch(Exception e) CAc]SxLh
{ AON |b\?
e.printStackTrace (); >)K3
} !/}4_s`,
} /o4_rzR?
UA.Tp[u
//日志 0Px Hf*
public static void log(String sMsg) JlSqTfA
{ yD<#Q\,
System.err.println(sMsg); t3$cX_
} ytj});,>
91z=ou
l i<9nMZ<
public static void log(int sMsg) =)bOteWM
{ Ls2OnL9
System.err.println(sMsg); @6ckB (
} )nHMXZ>Td
} MQ =x:p{
Z&^vEQ
7Ydqg&
/* N)(m^M(~0
**TestMethod.java p7+{xXf
*/ 1 k!gR
package NetFox; W<<G 'Km
6`9QGi,)
pRfKlTU\
public class TestMethod { UusAsezm:
VsA_x
(B\Kb4m
public TestMethod() y1 a%f.F`
{ ///xx/weblogic60b2_win.exe zDYJe_m ~
try{ yi^X?E{WnX
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); !wAnsK
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); >XZ2w_
SiteFileFetch fileFetch = new SiteFileFetch(bean); 2\{/|\
fileFetch.start(); ]9@4P$I
} Rs<S}oeLn
catch(Exception e){e.printStackTrace ();} qo9&e~Y<G
x6>WvFZ
44QW&qL!(
} bHTf{=
,JH*l:7
#NT~GhWFf
public static void main(String[] args) LEKE+775
{ a3A-N] ;f
new TestMethod(); ~a=]w#-KD
} AYNz {9
} <!dZ=9^^1
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