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)); EPnB%'l\c
} 8gm[Q[
for(int i=0;i<nEndPos.length-1;i++) 6{WT;W>WT:
{ *heQ@ww
nEndPos = nStartPos[i+1]; D];([:+4
} cSDCNc*%
nEndPos[nEndPos.length-1] = nFileLength; Z}StA0F_
} ,OAWGFKOp
} d>psqmQ
_Hj,;Z
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//启动子线程 %=eD)p7l-
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; hKeh9 Bt
for(int i=0;i<nStartPos.length;i++) <u/({SZ&
{ Md{f,,E'^@
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), tJ=zk3BN~
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), %,RU)}
nStartPos,nEndPos,i); eA^|B zU
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); @eU/g![u
fileSplitterFetch.start(); UbH=W(%
} $ayD55W4
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), P*sCrGO%
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Sd11ZC6
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", e 3oIoj4o
nEndPos = " + nFileLength); VH65=9z
// fileSplitterFetch[nPos.length-1].start(); KphEw[4/
El}z^e
_%!hkc(
//等待子线程结束 F\<i>LWT'
//int count = 0; Sp:de,9@
//是否结束while循环 .?:~s8kB
boolean breakWhile = false; _zwuK1e
M/;g|J jM
.1}(Bywm5
while(!bStop) ?!Gt. fb
{ 7|Y8^T s
write_nPos(); t/(j8w
Utility.sleep(500); )}5rs
breakWhile = true; b7mP~]V
&T}e93]
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for(int i=0;i<nStartPos.length;i++) =p$Wo
{ 1t'\!
if(!fileSplitterFetch.bDownOver) Ne_>%P|I_
{ ')<$AMy1
breakWhile = false; x|5/#H
break; 5Px_vtqP
} OD|&qsbL
} yRDLg c
if(breakWhile) VvKH]>*
break; `#U6`[[
+__Rk1CVh
S0yT%V
//count++; na)ceN2h
//if(count>4) T94$}- 5/)
// siteStop(); d0az#Yg!
} )G&OX
"'(4l 2.
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System.err.println("文件下载结束！"); ]f?LQCTq<b
} 0g\&3EvD
catch(Exception e){e.printStackTrace ();} 9 |Y?#oZ1
} Mt>DAk
Fjb[Ev
d-aF-
//获得文件长度 mH"`46
public long getFileSize() Q<qIlNE
{ @hPbD?)M
int nFileLength = -1; <Jz>e}*)
try{ XMdYted
URL url = new URL(siteInfoBean.getSSiteURL()); 6D<A@DR9J
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !$HWUxM;p
httpConnection.setRequestProperty("User-Agent","NetFox"); jL<.?HE
]gZjV
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int responseCode=httpConnection.getResponseCode(); :nt%z0_
if(responseCode>=400) ~MX@-Ff
{ ^y,ip=<5\3
processErrorCode(responseCode); 3ssio-X
return -2; //-2 represent access is error p"Y=
} T}*'9TB
hV)I C9
MRc^lYj{
String sHeader; *RO ~%g
[A47OR
CgWj9 [
for(int i=1;;i++) Pcc%VQN
{ &~8}y+z
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); Z[VKB3Pb8
//Utility.log(in.readLine()); g@L4G?hLn
sHeader=httpConnection.getHeaderFieldKey(i); (Lp-3Xx
if(sHeader!=null) K^ lVng
{ Gex^\gf
if(sHeader.equals("Content-Length")) %oo&M;
{ {T9g\F*
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); kMA>)\
break; tznT*EQr
} jWz-7BO
} 1N&U{#4
else U&NOf;h$
break; nJnan,`W
} FYJB.lAT
} '"EOLr\Z,
catch(IOException e){e.printStackTrace ();} *HRRv.iQ
catch(Exception e){e.printStackTrace ();} t9}XO M*
f W )
?#'qY6 ^
Utility.log(nFileLength); j.K yPWO
,\M'jV"SK
?g&]*zc^\
return nFileLength; \ gN) GR
} |w5#a_adM
VF-d^AGt
h$!qb'|
//保存下载信息（文件指针位置） 2-~oNJqX
private void write_nPos() fjb2-K
{ ]8#{rQ(
try{ 5^k#fl2
output = new DataOutputStream(new FileOutputStream(tmpFile)); 9fiZ5\
output.writeInt(nStartPos.length); U6Qeode
for(int i=0;i<nStartPos.length;i++) =cQwR:):
{ ATU@5,9
// output.writeLong(nPos); 1\2 m'o
output.writeLong(fileSplitterFetch.nStartPos); [qz6_WOo
output.writeLong(fileSplitterFetch.nEndPos); aj\'qRrU$
} #[8gH>7
output.close(); R8E<;^?j
} L%DL n
catch(IOException e){e.printStackTrace ();} AYi$LsLhO
catch(Exception e){e.printStackTrace ();} hug12Cu
} ,ZSuo4
+38t82%YWo
VYwaU^
//读取保存的下载信息（文件指针位置） s-*XAnot
private void read_nPos() R8KL4g-d
{ +%yh@X6
try{ [Xrq+O,
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); cE3co(j
int nCount = input.readInt(); 5IepVS(>?v
nStartPos = new long[nCount]; (#:Si~3
nEndPos = new long[nCount]; ;9~z_orNQZ
for(int i=0;i<nStartPos.length;i++) _I9TG.AA.
{ GHkSU;})
nStartPos = input.readLong(); ,%C$~+xjM
nEndPos = input.readLong(); (mEZ4yM
} ;(sb^O
input.close(); ]8^2(^3ct
} WM#!X!Vo
catch(IOException e){e.printStackTrace ();} AIeYy-f
catch(Exception e){e.printStackTrace ();} 0C7"*H0R
} bhI8b/
S$#Awen"@
myo/}58Nv
private void processErrorCode(int nErrorCode) )-9/5Z0v
{ [kXe)dMX8
System.err.println("Error Code : " + nErrorCode); =FE,G*
} $$4% .J26Z
4@5<B
X>CYKRtb
//停止文件下载 DFiexOb
public void siteStop() (X8N?tJ
{ L]VK9qB
bStop = true; T&c[m!}X|t
for(int i=0;i<nStartPos.length;i++) 7+c@pEU]
fileSplitterFetch.splitterStop(); r'8e"pTi
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4e:hKv,+4
} e'ZgF~
} Wj3H y4
//负责部分文件的抓取 aV ^2
**FileSplitterFetch.java 8dpVB#]pp,
*/ -&&mkK B!
package NetFox; P)H%dJ^l
TQ BL!w
WlY%f}ln
import java.io.*; PQ5DTk
import java.net.*; -{<%Wt9
B)(A#&nrb
#qPk,a
public class FileSplitterFetch extends Thread { C?|gf?1p
>!$4nxq2>
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String sURL; //File URL Y5;:jYk#<_
long nStartPos; //File Snippet Start Position +V) (,f1
long nEndPos; //File Snippet End Position QW!'A`*x
int nThreadID; //Thread's ID y0Tb/&xN
boolean bDownOver = false; //Downing is over >?kt3.IQ!X
boolean bStop = false; //Stop identical YONg1.^!(
FileAccessI fileAccessI = null; //File Access interface JmBYD[h,
kN_LD-
h$k(|/+
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException T7,tJk,(
{ ^a(q7ZfY
this.sURL = sURL; u]}Xq{ZN
this.nStartPos = nStart; |9g*rO
this.nEndPos = nEnd; U3Q'ZT
nThreadID = id; 4, :D4WYWD
fileAccessI = new FileAccessI(sName,nStartPos);//定位 Wc)^@f[~<
} w"D"9G
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Ro1l:P)C`
public void run() [)a,rrhj
{ GY!&H"%
while(nStartPos < nEndPos && !bStop) 9uq| VU5
{ A_g'9
3w-0v"j U
mF_/Rhu
try{ )j$Bo{
URL url = new URL(sURL); -H]svOX
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); $Fn# b|e
httpConnection.setRequestProperty("User-Agent","NetFox"); 8xNKVj)@
String sProperty = "bytes="+nStartPos+"-"; (R0
httpConnection.setRequestProperty("RANGE",sProperty); H'Po
Utility.log(sProperty); c"|^Lo.
Wbc %G8
mX#T<_=d
InputStream input = httpConnection.getInputStream(); zR/ATm]9
//logResponseHead(httpConnection); {c$W-t):U|
$%jV%k
M_PL{
byte[] b = new byte[1024]; d BJM?/
int nRead; 3:C *'@
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) MXhS\vF#m
{ 9|go`^*.
nStartPos += fileAccessI.write(b,0,nRead); /E*P0y~KTW
//if(nThreadID == 1) ]M2>%Dvw
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); TKmC/c
} UqAvFCy
ljk-xC p/
_Q7)FK
Utility.log("Thread " + nThreadID + " is over!"); @P8q=j}l9
bDownOver = true; R)H@'X
//nPos = fileAccessI.write (b,0,nRead); ~"LOw_BRh
} Wl*\kQ}U
catch(Exception e){e.printStackTrace ();} 0!^{V:DtQ
} UgUW4x'+
} jW6@U%[!b
wOOPuCw?
kt@+UK."
//打印回应的头信息 h rZ\ O?j
public void logResponseHead(HttpURLConnection con) Qdtfi1_Y1
{ ";GLX%C!{@
for(int i=1;;i++) 9eV@v
{ =7jkW (Q
String header=con.getHeaderFieldKey(i); aC:rrS
if(header!=null) D3jP hPy.
//responseHeaders.put(header,httpConnection.getHeaderField(header)); UH)A n:9
Utility.log(header+" : "+con.getHeaderField(header)); Z(V4"x7F
else EswM#D9(4
break; [6c{t
} >si<VCO
} 2Aff3]-:Gd
<|.M]]}j
kQj8;LU
public void splitterStop() H6~QSe0l
{ alq>|,\x
bStop = true; }e82e
} Kr9 @
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6#.R'O
} l lQ<x
jx-W$@
K%Rx5 S
/* ' rXkTm1{
**FileAccess.java LDbo
*//文件访问(定位，写) ;ymUMQ%;/
package NetFox; r*kk/$,2
import java.io.*; n9)/(=)>*
haY.rH]z
]qrO"X=
public class FileAccessI implements Serializable{ <8H`y(S
[jafPi(#g
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 c|I{U[(U
RandomAccessFile oSavedFile; xOS4J+'s@
long nPos; LEk W^Mv
^*Ca+22xO
af> i
public FileAccessI() throws IOException b|4h2iuM
{ 2#sE\D
this("",0); p[W8XX
} 1N2:4|woe
d`v]+HK
ty(F;M(
public FileAccessI(String sName,long nPos) throws IOException br0gB3r
{ {lqnn n3
oSavedFile = new RandomAccessFile(sName,"rw"); \b' <q
this.nPos = nPos; {At1]>
oSavedFile.seek(nPos); ]2v31'
} W~gFY#w
sYeZ.MacU
vZ|m3;X
public synchronized int write(byte[] b,int nStart,int nLen) Bm^vKzp
{ {y :/9
int n = -1; 7|H !(a'
try{ 2&P'rmFm
oSavedFile.write(b,nStart,nLen); fLPB *y6
n = nLen; 3:S Ex;d+
} V}3.K\7
catch(IOException e) * \f(E#wa
{ ;@Ls"+g
e.printStackTrace (); uI+h9j$vS
} ][D<J0
?-*_v//g
)=8X[<^i
return n; _4.fT
} _ 57m] ;&
Y]ZOvA5W
='YR;
} fNQ.FAK":
fU$zG"a_
xpUaFb
/* -<qci3Ba}
**SiteInfoBean.java rW!P~yk
*/ \u:xDS(
package NetFox; wS8qua
nIXq2TzJ
:fo%)_Jc!
public class SiteInfoBean { 1P&c:n
R$NH [Tz
YQ2ie>C8
private String sSiteURL; //Site's URL *O+YhoR?
private String sFilePath; //Saved File's Path ,HR~oT^
private String sFileName; //Saved File's Name K+PzTGWq^
private int nSplitter; //Count of Splited Downloading File 0E{$u
P|c79
+d]}
public SiteInfoBean() u|B\@"0
{//nSplitter的缺省值为5 \O`B@!da~
//default value of nSplitter is 5 hE+6z%A8
this("","","",5); %I[(`nb
} .-fJ\`^mi
hyFq>XFo
TRG"fVR
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) GIt;Y
{ 'V .4Nhd
sSiteURL= sURL; Spt[b.4mF
sFilePath = sPath; ^[lg1uMW
sFileName = sName; _qM'm^z5
this.nSplitter = nSpiltter; ;?bRRW
*p p1U>,
pT:CvJ
} &A]*"lt|w
]MRE^Je\h
8K7zh.E
public String getSSiteURL() rB)m{)
{ 'GS1"rkW<5
return sSiteURL; A\k@9w\Ll;
} DBbmM*r
-Z)$].~|t
0g~WM
public void setSSiteURL(String value) ^=}~
{ E.t9F3
sSiteURL = value; {SJ=|L6
} WSKG8JT^|
I Yj\t?,0
WUMx:a0!
public String getSFilePath() &YDb/{|CIC
{ XBdC/DM[
return sFilePath; No!P?
} +.mIC:9
!nC Z,
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public void setSFilePath(String value) ~`u?|+*BO
{ c-n'F+fZ
sFilePath = value; wnN@aO6g*
} 9c46|
dGrOw)
5d<-y2!M
public String getSFileName() coiTVDwA
{ O=G2bdY{,
return sFileName; v5RS<?o
} !634 8nU:
v93+<@Z
R1\cAP^0
public void setSFileName(String value) Y:ZI9JK?
{ X_!Sm
sFileName = value; z@{|Y;s
} ko>SnE|w#
3JWHyo
L5]*ZCDv
public int getNSplitter() Gq$9he<
{ u'<Y#bsR#/
return nSplitter; 2P"@=bYT"
} [}+0NGgR
(S=::ODU
*<OWd'LI
public void setNSplitter(int nCount) w[n|Sauy,
{ 3T|:1Nw
nSplitter = nCount; 6WzE'0Nyr
} VgN`' iC`I
} #}^ZxEU
gh['T,
K&Ht37T
/* 9L*gxI>
**Utility.java &:nWZ!D
*/ mAX]m1s
package NetFox; -P!vCf^{ t
sO~N2
1W"9u
public class Utility { Cx} Yp-
oy;N3
WIQt5=-
public Utility() kZWc(LwA
{ iEsI
8n,i5>!d
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} rPZ<
3Yp_k
//线程睡眠 OHR9u
public static void sleep(int nSecond) ]9]3=;b>
{ ZL+{?1&-
try{ Wu2#r\
Thread.sleep(nSecond); T=A7f6`
} LrsP4G
catch(Exception e) 1x V~EX
{ B@63=a*kG
e.printStackTrace (); :2 n5;fp
} [64K?l0&
} C;OU2,c,T
tv,^ Q}
//日志 vpMNulXb,
public static void log(String sMsg) H2zd@l:R
{ Km'd=B>Jy
System.err.println(sMsg); VjMd&>G
} fFqK.^Tn
.]k(7F!W
%Jq(,u
public static void log(int sMsg) q}M^i7IE
{ C' o4Su#
System.err.println(sMsg); 3Nsb@0
} Ni(D[?mZ
} @j9yc
3r%I *
b,#cc>76\
/* Vj:)w<],
**TestMethod.java ygd'Nh!@
*/ #D .H2'_}
package NetFox; <T+Pw7X
Yc"G="XP;
__-rP
public class TestMethod { qV@xEgW#r
F'C]OMBE
Yu9Ccj`
public TestMethod() g5M-Vu
{ ///xx/weblogic60b2_win.exe |2 g }i\
try{ Ipb4{A&"\
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); &julw;E
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); V<\:iNXX{
SiteFileFetch fileFetch = new SiteFileFetch(bean); gA`/t e
fileFetch.start(); ?$Uk[
} <$Q&n{
catch(Exception e){e.printStackTrace ();} 8T&m{s
)fA9,yNJ3
-+'{C=
} pE^LQi
5u~Ik c~
deda=%w0
public static void main(String[] args) z=?ainnKx
{ Nr|.]=K)5n
new TestMethod(); ^X)U^Qd
} x*}(l%[
} &.K8cphj
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