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)); c4E=qgP
} qc;9{$?xV
for(int i=0;i<nEndPos.length-1;i++) rf?Q# KM\W
{ Z<T%:F
nEndPos = nStartPos[i+1]; Ju4={^#
} gh>'O/9
nEndPos[nEndPos.length-1] = nFileLength; ^kA^>vi
} zcnp?%
} 1$vsw
dP}=cZ~
KAH9?zI)M
//启动子线程 2A'!kd$2
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; U`Bw2Vdk]S
for(int i=0;i<nStartPos.length;i++) Uv?s<
{ Q$r1beA
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Vw0cf;
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), u?6L.^Op
nStartPos,nEndPos,i); gx~79;6
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); /ZlPEs)
fileSplitterFetch.start(); hDTiXc
} b.V\EOk
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 1D159NLB
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 3}V`]B#a
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", X;25G
nEndPos = " + nFileLength); 4 qMO@E_
// fileSplitterFetch[nPos.length-1].start(); IMjz#|c
#Ux*":
GAG=4g
//等待子线程结束 QwPLy O
//int count = 0; .4DX/~F
//是否结束while循环 ~7a(KJgvd"
boolean breakWhile = false; GZXBzZ}
BBnW0vAZ*
=g|e-XC
while(!bStop) zG)XB*c
{ j}}:&>;
write_nPos(); |eH>55 b
Utility.sleep(500); e%.Xya#\
breakWhile = true; Hg$t,\j
NGZEUtj
R+,eXjz"
for(int i=0;i<nStartPos.length;i++) m:U.ao6
{ gw[\7
if(!fileSplitterFetch.bDownOver) `@?f@p$(B
{ <,/k"Y=
breakWhile = false; 9ReH@5_bGM
break; Sz4G,c
} g_'F(An
} r,F~Vwa}
if(breakWhile) yM}b
break; R(_UR)G0 @
<Th)&
{v{qPYNyh
//count++; g%z'#E97
//if(count>4) }@Rq'VPZd
// siteStop(); n/*BK;
} /Xa_Xg7
^Qrezl&
.u[hK
System.err.println("文件下载结束！"); e_mUO"
} )c~1s
catch(Exception e){e.printStackTrace ();} <k'JhMwN
} RW19I,d
` O;+N"v
?S&pq?
//获得文件长度 m2&"}bI{
public long getFileSize() 'wh2787
{ Fl)p^uUtl
int nFileLength = -1; f%r0K6p
try{ [>+}2-#
URL url = new URL(siteInfoBean.getSSiteURL()); \GA6;6%Oo
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); s%Ez/or(T
httpConnection.setRequestProperty("User-Agent","NetFox"); I{>U7i 5
N$#518
4-lG{I_S:
int responseCode=httpConnection.getResponseCode(); 8w,U[aJm
if(responseCode>=400) $r0~&$T&
{ x\HHu]
processErrorCode(responseCode); t\YN\`XD
return -2; //-2 represent access is error d:KUJ Y.
} .1F(-mLd
xRum q
UG)J4ZX
String sHeader; zQY|=4NP
N~I2~f
Qn`$xY9mT
for(int i=1;;i++) iaShxoIV
{ yL =*yC
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ]WZ_~8
//Utility.log(in.readLine()); Ml &Cr
sHeader=httpConnection.getHeaderFieldKey(i); #=6A[<qX
if(sHeader!=null) 8&?kr/_Vr
{ Vq[L4
if(sHeader.equals("Content-Length")) GJlkEWs
{ %4X#|22n
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ;uw`6 KJ
break; wk @-O}W
} ~~J xw ]
} &+t! LM
else gcLwQ-
break; MDETAd
} \)H}
} NpS*]vSO
catch(IOException e){e.printStackTrace ();} V?KACYd@O
catch(Exception e){e.printStackTrace ();} 8NY$Iw
9rhIDA(wc
N^,@s"g
Utility.log(nFileLength); kz4d"bTb
Be?b| G!M
{P'TtlEp
return nFileLength; tnx)_f
} 'k|?M
v9Kx`{1L
"YIrqk
//保存下载信息（文件指针位置） \;"$Z9W
private void write_nPos() Bvbv~7g(
{ 'EsN{.l?
try{ &V.ps1
output = new DataOutputStream(new FileOutputStream(tmpFile)); F_8< tA6
output.writeInt(nStartPos.length); .}KY*y
for(int i=0;i<nStartPos.length;i++) 8J60+2Wa
{ #ma#oWqF}
// output.writeLong(nPos); +h!OdWD9
output.writeLong(fileSplitterFetch.nStartPos); jVh I`F{n
output.writeLong(fileSplitterFetch.nEndPos); {/f\lS.5g
} FmU>q)
output.close(); *Q=3v
} iTb k]$
catch(IOException e){e.printStackTrace ();} wSrq?U5q
catch(Exception e){e.printStackTrace ();} VlGg?
} JzhbuWwF-
We^!(G
dV{N,;z
//读取保存的下载信息（文件指针位置） M>Yge~3
private void read_nPos() 1$cX`D`
{ [8Zq 1tU;G
try{ RI,Z&kXj2o
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); V{51wnxT
int nCount = input.readInt(); lZpa)1.tiC
nStartPos = new long[nCount]; Ave{ `YD
nEndPos = new long[nCount]; C[cNwvz
for(int i=0;i<nStartPos.length;i++) NzRpI5\.
{ BIx Z4Ft
nStartPos = input.readLong(); PFP/Pe Ng;
nEndPos = input.readLong(); )ESF)aKMiz
} h-"c )?p
input.close(); B?}ZAw>
} wd4wYk\
catch(IOException e){e.printStackTrace ();} h/9{E:ML
catch(Exception e){e.printStackTrace ();} L0j&p[(r
} GyE-fB4C
yHvF"4]
6>I{Ik@>
private void processErrorCode(int nErrorCode) 7_$Xt)Y{
{ H^Th]-Zl
System.err.println("Error Code : " + nErrorCode); 2LpJxV
} ZzDE
7C7eXJ9q
rh;@|/<l
//停止文件下载 u&Ze$z
public void siteStop() !ueyVE$1
{ W/dl`UDY
bStop = true; XqD/~_z;
for(int i=0;i<nStartPos.length;i++) }*+?1kv
fileSplitterFetch.splitterStop(); 'BE &lW
{Vz.| a[T
.r~!d|
} .]_Ye.}
} z6B(}(D
//负责部分文件的抓取 J\iyc,M<M
**FileSplitterFetch.java mp2J|!Lx
*/ -7_`6U2"
package NetFox; 2l43/aCq
UL0%oJ#
]e0yC
import java.io.*; zh2gU@"
import java.net.*; R(dVE\u
sS$"6
w#v8a$tT
public class FileSplitterFetch extends Thread { Z P\A
Wb!"L`m
)wU.|9o]M
String sURL; //File URL JX_hLy@`
long nStartPos; //File Snippet Start Position YmP`Gg#>p
long nEndPos; //File Snippet End Position 3JuWG\r)l
int nThreadID; //Thread's ID dQfVdqg
boolean bDownOver = false; //Downing is over i#I+
boolean bStop = false; //Stop identical hdB.u^!
FileAccessI fileAccessI = null; //File Access interface a9rn[n1Q
P.bBu
cnm&oC 6
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException :Mz$~o<
{ S1Q2<<[
this.sURL = sURL; \79KU
this.nStartPos = nStart; voRr9E*n
this.nEndPos = nEnd; cP[3p:
nThreadID = id; *2O4*Q1
fileAccessI = new FileAccessI(sName,nStartPos);//定位 F.P4c:GD
} !;'.mMO&%
r&AX
=2HR+
public void run() & [)1LRt_
{ e|:#Y^
while(nStartPos < nEndPos && !bStop) J8|F8dcz
{ >*ey 7g
#E`-b9Q
Z5aU7
try{ A^+G w\
URL url = new URL(sURL); fFD:E} >5
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ?haN ;n6'
httpConnection.setRequestProperty("User-Agent","NetFox"); Y40Hcc+Fx
String sProperty = "bytes="+nStartPos+"-"; k%w5V>]1
httpConnection.setRequestProperty("RANGE",sProperty); G#.(%,
Utility.log(sProperty); 4&r+K`C0
0T,Qn{
sW)C6 #
InputStream input = httpConnection.getInputStream(); j-2`yR
//logResponseHead(httpConnection); @=o1q=5@8
Q9X7-\n
bSmF"H0cP
byte[] b = new byte[1024]; FY%v \`@1*
int nRead; i3I'n*
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) XGE:ZVpW
{ g0ec-
nStartPos += fileAccessI.write(b,0,nRead); @NMFurm
//if(nThreadID == 1) p"4i(CWGS
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); k$</7IuH
} ra\Moy
mG[S"?C
uSSnr#i^j
Utility.log("Thread " + nThreadID + " is over!"); iTTe`Zr5y
bDownOver = true; '0_Z:\ laU
//nPos = fileAccessI.write (b,0,nRead); d#:&Uw
} T.kmoLlH
catch(Exception e){e.printStackTrace ();} `+17x<N
} S -j<O&h~C
} .uzg2Kd_
]_NN,m>z
"oZ]/(
//打印回应的头信息 %FnaS u
public void logResponseHead(HttpURLConnection con) m%ZJp7C
{ %V-\|cw
for(int i=1;;i++) &.ZW1TxE8
{ D$g|f[l
String header=con.getHeaderFieldKey(i); $M\|zUQu.
if(header!=null) iTgGf
//responseHeaders.put(header,httpConnection.getHeaderField(header)); -|^}~yOx0=
Utility.log(header+" : "+con.getHeaderField(header)); b#0y-bR
else j`I[M6Qxh
break; LjUBV_J
} }^uUw&
} =ECw'
@xR7>-$0p
)e.Y"5My
public void splitterStop() v)@EK6Nty
{ frS1<+
bStop = true; LO@.aJpp
} %Kd&A*
,]@K6
q;3,}emg
} kYBTmz}z
}B2H)dG^K
)@.bkzW
/* Tyu]14L
**FileAccess.java 7kU:91zR
*//文件访问(定位，写) REnd# V2x
package NetFox; w)-@?jN
import java.io.*; 87%t=X
P9Hv){z
Lv@JfN"O
public class FileAccessI implements Serializable{ qq}EXq^
{<~0nLyJS
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 }J .f 5WaG
RandomAccessFile oSavedFile; a,o)i8G9R<
long nPos; nd 'K4q
2V(ye9
LLv~yS O
public FileAccessI() throws IOException :kSA^w8
{ D+{h@^C9Z
this("",0); ?&Si P-G
} JDv7jy
K[RlR+j
xP3_
public FileAccessI(String sName,long nPos) throws IOException S/-[OA>N
{ TkhbnO g6
oSavedFile = new RandomAccessFile(sName,"rw"); uEQH6~\{Nl
this.nPos = nPos; I@P[}XS
oSavedFile.seek(nPos); kzr9-$eb
} :@w ;no>=*
21GjRPs\
,c"_X8Fkx$
public synchronized int write(byte[] b,int nStart,int nLen) QytqO{B^
{ FH}n]T
int n = -1; {snLiCl
try{ q@;WXHO0
oSavedFile.write(b,nStart,nLen); a?6 r4u0
n = nLen; x.ZV<tDi7
} jEfrxlj
catch(IOException e) .!0),KmkK
{ @K36?d]e
e.printStackTrace (); a$Eqe_
} F7J-@T<
&,+G}
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return n; =zXpeo&|m
} S!8eY `C.
~Kda#=
`),7*gn*)
} N;tUrdgQ
h4H~;Wl0
d{&+xl^ll
/* PCnE-$QH
**SiteInfoBean.java M$#zvcp
*/ ug[|'tR8
package NetFox; BZEY^G
tu6oa[s
CF9a~^+%
public class SiteInfoBean { o%h"gbvMY!
|$Dt6{h
qa#Fa)g*
private String sSiteURL; //Site's URL s<'^ @Y
private String sFilePath; //Saved File's Path %KNnss}
private String sFileName; //Saved File's Name bO1J#bcZ
private int nSplitter; //Count of Splited Downloading File 6~?7CK
sLK J<=0i
vn3<LQ]
public SiteInfoBean() x*}j$n(Oa
{//nSplitter的缺省值为5 /pgfa-<
//default value of nSplitter is 5 Xtbuy/8"1
this("","","",5); hXM8`iFW5
} !uLAW_~
_1hc^j
,kuJWaUC@
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) [&t3xC,
{ OGg9e
sSiteURL= sURL; 2H;&E1:
sFilePath = sPath; ^Tc&?\3
sFileName = sName; </tiNc
this.nSplitter = nSpiltter; ,)'!E^n
A?|KA<&m#u
&+6XdhX
} "5Oog<
pez*kU+9
o,9E~Q'`{
public String getSSiteURL() u /JEQz1
{ ESiNW&u2
return sSiteURL; |;'V":yDs
} YNc%[S[u^1
?|TVz!3
En8-Hc#NC
public void setSSiteURL(String value) X<\^*{
{ K6~N{:.s
sSiteURL = value; ??=CAU%\
} /ivt8Uiw
,,mkB6;
O^G/(
public String getSFilePath() l*uNi47|
{ qd~)Ya1
return sFilePath; \.myLkm
} b')CGqbbmT
H)tYxW
<%hSBDG!x
public void setSFilePath(String value) #6fp"
{ H&E c*MT
sFilePath = value; l-_voOP
} | ctGxS9
"p.MJxH
.x$+R%5U
public String getSFileName() J6Hw05%0=
{ . l RW
return sFileName; ] M"{=z
} ?'CIt5n+\{
pA"x4\s
8wwqV{O7
public void setSFileName(String value) Yfk[mo
{ af\>+7x93
sFileName = value; ;5=J'8f
} "uN JQ0Y
LT!B]y
qWKpnofa
public int getNSplitter() v~q2D"
{ {,*G}/9<
return nSplitter; ;nji<
} -Vn9YeH+
c?CwxI_b8
Mr<2I
public void setNSplitter(int nCount) oaHg6PT!
{ @Rj&9/\L
nSplitter = nCount; =DvFY]9{
} dl'pl
} e{:P!r aM
d,iW#,
2al%J%
/* !Y!Cv %
**Utility.java @JT9utct
*/ 5(1Zj`>'
package NetFox; Ul^/Dh
'I($IM
vvv~n]S6
public class Utility { T2Z;)e$m_
]G1{@r)
apF!@O^}y
public Utility() zAC
{ 9'o!9_j
cE/7B'cR
m'KY;C
} C&bw1`XJf
yTz@q>6s-
//线程睡眠 zwN;CD1
public static void sleep(int nSecond) -dsB@nPiUw
{ 2WIL0Siwl
try{ Pr{?A]dQ
Thread.sleep(nSecond); ?Bq"9*q
} :7D&=n)
catch(Exception e) jRm:9`.Q
{ L^KGY<hp4
e.printStackTrace (); O}MY:6Pe
} _Hl[Fit<j1
} Y]{<IF:
v{i'o4
//日志 !(*mcYA*W
public static void log(String sMsg) x|_%R v
{ zPe4WE|
System.err.println(sMsg); ! o:m*:
} M-K<w(,X
(;$J5
Vg#s
public static void log(int sMsg) ^5qX+!3r{
{ ; @ h{-@
System.err.println(sMsg); -?!|W-}@G=
} "L1cHP~d
} ]3 YJEP
SGZOfTcY
A,W-=TC
/* [VT&
**TestMethod.java {lT9gJ+
*/ im>Sxu@
package NetFox; ;tf1#6{
gd]vrW'wj
2*vOo^f
public class TestMethod { VjtI1I
}IC$Du#
r[vMiVb
public TestMethod() w (W+Y+up
{ ///xx/weblogic60b2_win.exe gAhCNOp
try{ %RL\t5TV
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Nm--h$G
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); E8T4Nh_
SiteFileFetch fileFetch = new SiteFileFetch(bean); @b=tjQO_
fileFetch.start(); 5`{+y]
} 5z~Ji77!
catch(Exception e){e.printStackTrace ();} FAjO-T4(
ZD6rD(l9
_b<Fz`V
} KwN o/x| v
?cG+rC%
r42[pi]F
public static void main(String[] args) a_^3:}i~D
{ mn{8"@Z
new TestMethod(); f~jx2?W
} o$'Fz[U
} >-r\]/^
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