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)); zmA]@'j
} ~}lYp^~:J
for(int i=0;i<nEndPos.length-1;i++) {;z{U;j
{ JJIlR{WY_
nEndPos = nStartPos[i+1]; E{LLxGAEZ
} oFO)28Btv
nEndPos[nEndPos.length-1] = nFileLength; r JvtE}x1
} q <, b
} 11'^JmKA
u-8b,$@Z>'
S.<aCN<@
//启动子线程 e;|:W A
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; A"SF^p
for(int i=0;i<nStartPos.length;i++) J?oI%r7^
{ t2L}
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ~CtLSyB
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), PRdyc+bf
nStartPos,nEndPos,i); 65%WjO
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); lx'^vK%F
fileSplitterFetch.start(); :V9%R~h/
} D(E3{\*R
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), mp!S<m
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); .S5%Qa [uW
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", '-,$@l#
nEndPos = " + nFileLength); 6`c5\G+
// fileSplitterFetch[nPos.length-1].start(); C`J>Gm
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;+Dq3NE
//等待子线程结束 As}eI!
//int count = 0; 2bs={p$}a
//是否结束while循环 3jI rB%
boolean breakWhile = false; 9}[UZN6
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VRb+-T7"
while(!bStop) J1s~w`,
{ Jbv[Ql#
write_nPos(); R&-Vm3mc3
Utility.sleep(500); 3}7`?$5
breakWhile = true; 2l4*6rYa(
'%H\k5^
zu,F 0;De
for(int i=0;i<nStartPos.length;i++) ,+d\@:
{ PeX^aEc
if(!fileSplitterFetch.bDownOver) [$Dzf<0
{ /e:kBjysJ
breakWhile = false; |]Eli%mNe
break; (u{?aG~
} h7P<3m}
} n@JZ2K4
if(breakWhile) '^{:HR#i
break; nF)b4`Nd
f@j)t%mh
f`gs/R
//count++; qk{+Y
//if(count>4) /q^\g4J
// siteStop(); m8T< x>
} n9%&HDl4
9n#lDL O
t@;r~Sb
System.err.println("文件下载结束！"); 5r)]o'?s
} d:L|BkQ7*
catch(Exception e){e.printStackTrace ();} 6CV9ewr
} m]?C @ina
$(r/N"6)O2
tKX+eA]
//获得文件长度 W5^<4Ya!
public long getFileSize() +F4SU(T
{ q`0wG3
int nFileLength = -1; )Jaq5OMA/
try{ iLbf:DXK(
URL url = new URL(siteInfoBean.getSSiteURL()); n/6qc3\5i
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); E*Z# fa
httpConnection.setRequestProperty("User-Agent","NetFox"); }T~}W8H
@}<b42
l+UUv]:1
int responseCode=httpConnection.getResponseCode(); T&q0TBT
if(responseCode>=400) ,\RZ+kC>~
{ s# 9*`K
processErrorCode(responseCode); pQNTN.L9NZ
return -2; //-2 represent access is error -<{;.~nI.
} u85dG7
+B&,$ceyaJ
'* eeup
String sHeader; ?/1Eu47
1PUeU+
@OGHS}-\
for(int i=1;;i++) N\t( rp
{ !de`K |
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 3JFX~"rV9I
//Utility.log(in.readLine()); XCd[<\l
sHeader=httpConnection.getHeaderFieldKey(i); 6%B)
if(sHeader!=null) ):-Ub4A\
{ _'0C70
if(sHeader.equals("Content-Length")) NZL$#bRB
{ pGdFeEkB/
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); "qdEu KI
break; >3?p23|;
} I/hq8v~S
} .Y5o&at6s
else EXEB A&*
break; 4de:hE
} GWa:C\YK
} ?0x=ascP
catch(IOException e){e.printStackTrace ();} -d4|EtN
catch(Exception e){e.printStackTrace ();} H7{I[>:
".7\>8A#a
8)ykXx/f@
Utility.log(nFileLength); mlO\wn-F
d#CAP9n;'
&e\UlM22
return nFileLength; X]4j&QB
} ]S 3l' "
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t`")Re_j
//保存下载信息（文件指针位置） cd(YH! 3
private void write_nPos() 6hiWgbE
{ c->.eL%
try{ (b8ZADI*
output = new DataOutputStream(new FileOutputStream(tmpFile)); :pdl2#5H^
output.writeInt(nStartPos.length); 85_Qb2<'r
for(int i=0;i<nStartPos.length;i++) (3?W)i
{ n.7-$1
// output.writeLong(nPos); &&ZX<wOM
output.writeLong(fileSplitterFetch.nStartPos); dCA! R"HD
output.writeLong(fileSplitterFetch.nEndPos); X#k:J
} g`(3r
output.close(); c<ORmg6
} dwqR,|
catch(IOException e){e.printStackTrace ();} \IP 9EFA
catch(Exception e){e.printStackTrace ();} PY MofQaZ
} ;~GBD]
1<;VD0XX
slQEAqG)B
//读取保存的下载信息（文件指针位置） UuCRQNH
private void read_nPos() 2QgD<
{ oc"7|YG
try{ 4+J>/ xiZ
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); qH(HcsgD
int nCount = input.readInt(); 8?LHYdJ
nStartPos = new long[nCount]; @xeJ$ rlu
nEndPos = new long[nCount]; tz9"#=}0
for(int i=0;i<nStartPos.length;i++) tu's]3RE
{ abw5Gz@Ag
nStartPos = input.readLong(); T|-llhJ8
nEndPos = input.readLong(); )fl+3!tq
} PJPKn0,W
input.close(); DN;|?oNZ
} ]Q#k"Je
catch(IOException e){e.printStackTrace ();} gKP=@v%-
catch(Exception e){e.printStackTrace ();} 8GeJ%^0o}
} FEdFGT
@rS(3wu_&
9v/=o`J#
private void processErrorCode(int nErrorCode) t=fr`|!
{ Zi}jf25
System.err.println("Error Code : " + nErrorCode); E:y^= Y
} n.XgGT=L
,uPN\`.u8
,AH2/^:%c
//停止文件下载 q[(1zG%NbA
public void siteStop() 05Q4$P
{ biPj(Dd
bStop = true; I)MRAo
for(int i=0;i<nStartPos.length;i++) {f\{{JJ]
fileSplitterFetch.splitterStop(); ~KczP1p
3e9UDN2
]app9
} #nq_R
} "u)e,gu
//负责部分文件的抓取 $Lz!04
**FileSplitterFetch.java =fJ /6
*/ &$ fyY:<\
package NetFox; WWTRB +1>
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f!F5d1N
import java.io.*; v]#[bqB.b
import java.net.*; i>KgkRZL#
n~ZZX={a
<}G/x*N
public class FileSplitterFetch extends Thread { rv c%[HfW;
Za]~[F
vX_;Y#uD
String sURL; //File URL /VD[:sU7
long nStartPos; //File Snippet Start Position UrO&K]Z
long nEndPos; //File Snippet End Position S`Z[MNY
int nThreadID; //Thread's ID :j? MEeu
boolean bDownOver = false; //Downing is over 6xFchdMG{m
boolean bStop = false; //Stop identical *z};&UsF{
FileAccessI fileAccessI = null; //File Access interface I|wC`VgB
kt |j]:
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException N'CWSf.e
{ ' e %>Ip
this.sURL = sURL; ~x^Ra8A
this.nStartPos = nStart; {Ve3EYYm
this.nEndPos = nEnd; qP-_xpu]R
nThreadID = id; ix"BLn]YZ
fileAccessI = new FileAccessI(sName,nStartPos);//定位 #pyFIUr=w
} 7\N }QP0"u
Y`3\Z6KlV
Pif-uhOk%
public void run() xd\ml 37~
{ L)qUBp@MW
while(nStartPos < nEndPos && !bStop) }a;H2&bu
{ CF:L#r
S f6%A
jO9!:L>b`
try{ nNeCi
URL url = new URL(sURL); _9dW+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); NKc<nYdK?
httpConnection.setRequestProperty("User-Agent","NetFox"); (*kKfg4Wj
String sProperty = "bytes="+nStartPos+"-"; 9I*2xy|I
httpConnection.setRequestProperty("RANGE",sProperty); Ta$55K0
Utility.log(sProperty); uw/N`u
Sk-Q 4D^
Lyz8DwZ
InputStream input = httpConnection.getInputStream(); B6@q`Bmw.
//logResponseHead(httpConnection); VK!HuO9l
$)~:H-
,& wd
byte[] b = new byte[1024]; _SkiO}c8
int nRead; 9Vl}f^Gn
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) {|@}xrB
{ L={\U3 __k
nStartPos += fileAccessI.write(b,0,nRead); wR,}#m,
//if(nThreadID == 1) ^j2ve's:
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); L c )i
} o'Fyo4Qd
abv*X1
<oi'yr
Utility.log("Thread " + nThreadID + " is over!"); 3h$E^"
bDownOver = true; ~7FS'!W,F
//nPos = fileAccessI.write (b,0,nRead); j#u{(W'r
} YkE_7r(1
catch(Exception e){e.printStackTrace ();} #^yOW^
} 4|\
} !p76I=H%
2%pU'D:
_BONN6=*y
//打印回应的头信息 e*}:tH
public void logResponseHead(HttpURLConnection con) ysPm4am$
{ l*{Bz5hc
for(int i=1;;i++) HCCq9us
{ X{(?p=]
String header=con.getHeaderFieldKey(i); SurreD<x
if(header!=null) g7^|(!Y%
//responseHeaders.put(header,httpConnection.getHeaderField(header)); a47e
Utility.log(header+" : "+con.getHeaderField(header)); n 83Dt*O
else f96`n+>xi
break; i8p$wf"aW
} m#R"~ >
} p1hF.
MK1#^9Zr
sSc~q+xz
public void splitterStop() `%^w-'
{ )Gk?x$pY@
bStop = true; vexF|'!}0#
} EZzR"W/
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mU
} D>;_R HK
"shX~zd5
WnOvU<Z <
/* 'Z:wEt!
**FileAccess.java KFRf5^%
*//文件访问(定位，写) `(gQw~|z
package NetFox; ';!-a]N
import java.io.*; }p-/R'
:>Bk^"
*B\ @L
public class FileAccessI implements Serializable{ 6!?] (
Ekik_!aB
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 fJ0V|o
RandomAccessFile oSavedFile; P;K LN9/4
long nPos; CrSBN~
N-t"CBTO
iz)r.TJ
public FileAccessI() throws IOException ]N;nq
{ mq:WBSsV
this("",0); US=K}B=g
} )Vrp<"v
` AD}6O+x
edCVIY'1
public FileAccessI(String sName,long nPos) throws IOException %IE;'aa }
{ jKo9y
oSavedFile = new RandomAccessFile(sName,"rw"); ; yE.R[I
this.nPos = nPos; WPrBK{B`o
oSavedFile.seek(nPos); E:k]Z
} e igVT4
^*+M9e9Z
z@o6[g/*Q
public synchronized int write(byte[] b,int nStart,int nLen) (C1~>7L
{ VbMud]40F
int n = -1; P-$ ,
try{ SS24@:"{
oSavedFile.write(b,nStart,nLen); Slj U=,
n = nLen; KATf9-Sz
} c~ vql4
catch(IOException e) ==gL!e{
{ mdQe)>
e.printStackTrace (); rNKeY48\
} _~{J."q
P;-.\VRu
2VUN
return n; Iz83T9I&
} Q`6hJgyL
$tXW/
l_$>$d
} 0I:5}$+J?
zUDXkG*Lv
Y0-?"R8
/* +?ZP3vgGA
**SiteInfoBean.java B0Ay
*/ Mw"[2PA
package NetFox; 8a]g>g
6J#R1.h
w^^l,
public class SiteInfoBean { nd,\<}uP9
Y<kz+d,C
W(Md0*
private String sSiteURL; //Site's URL K'e,9P{
private String sFilePath; //Saved File's Path u"%D;
private String sFileName; //Saved File's Name It/hXND`
private int nSplitter; //Count of Splited Downloading File ~3%\8,0
dZ8ldpf8
I Z*)
public SiteInfoBean() (v KJyk+Y
{//nSplitter的缺省值为5 2hso6Oy/v{
//default value of nSplitter is 5 o2bmsnXQ
this("","","",5); hO{&bY0
} I$x<B7U
GVu[X?q@|
p:$kX9mT&
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) *JZ9'|v_H
{ S.`hl/
sSiteURL= sURL; z C$F@
sFilePath = sPath; xdDe@G;"
sFileName = sName; ~% t'}JDZ
this.nSplitter = nSpiltter; "#gS?aS
M;'GnGFf
\,n X/f
} EE|c@M^
J>G'H)
EAm31v C
public String getSSiteURL() 2~7*jA+Ab
{ @$L|
return sSiteURL; yiXb<g+B
} aIQC[ry
@Q{:m)\
nT2b"wkTT
public void setSSiteURL(String value) #`U?,>2q
{ Y,yU460T8
sSiteURL = value; s]`6uyW"
} %C #Ps
&iq'V*+-\
WA1yA*S
public String getSFilePath() \ZhkOl
{ 0S4Y3bac&
return sFilePath; n[qnrk*3 %
} /.rj\,
,3eN&
0bJT0_
public void setSFilePath(String value) $bF+J8%D
{ c+7I
sFilePath = value; | 2<zYY
} WBJn1
#*lDKn[vO
q[W@.[2y)
public String getSFileName() d2US~.;>l
{ 7QZyd-
return sFileName; \*BRFUAc
} I(3~BOUn_
$!!y v'K
Pg`+Q^^6S
public void setSFileName(String value) UY,u-E"
{ bA$ElKT
sFileName = value; ;14Q@yrZ0
} fhRu-
sh0x<_
Q%!xw(
public int getNSplitter() "}%j'
{ $sb@*K}:4
return nSplitter; -kP2Brm
} 9-&@Y
.YH#+T'
{|j-e{*
public void setNSplitter(int nCount) w)qmq
{ K.&6c,P]
nSplitter = nCount; &z*4Uij
} sAs`O@
} /#"9!8%V
yLnTIE3)
X}h}3+V
/* fpjFO&ML
**Utility.java .wWf#bB
*/ 8@rF~^-_
package NetFox; 4DP<)KX
OI:=>Bk
0$Zh4Y
public class Utility { FEopNDy@y
NU{eoqaT
qPUACuF'
public Utility() : 4lR`%
{ cFJZ|Ld
CR't
+]yVSns 3
} $:-C9N29
<; Td8O89_
//线程睡眠 ?;(!(<{
public static void sleep(int nSecond) JJM!pD\h
{ 0|0IIgy
try{ ,m7Z w_.
Thread.sleep(nSecond); 9!2$?xqym
} jE5=e</
catch(Exception e) nSZp,?^
{ Kuk@x.~0m
e.printStackTrace (); yTe25l{QaF
} fHI@' '0
} =M4wP3V/
[5M!'
//日志 VzcW9'"#
public static void log(String sMsg) /z)8k4
{ ,g|ht%"
System.err.println(sMsg); eUgKwu;
} n4"xVDL
9NU-1vd~
o@} qPvt0
public static void log(int sMsg) chE}`I?
{ P;&U3i
System.err.println(sMsg); %F;uW[4r
} SokU9n!
} :N xksL^
,>TDxI;
9~iDL|0'~
/* 5:EE%(g9
**TestMethod.java uIJ zz4
*/ ?4Zo0DiUB
package NetFox; z^%`sUgP
REk^pZ3B
%V!!S#W
public class TestMethod { :O;uP_r9
y>g`R^^
x^pHP|<3`
public TestMethod() SQuW`EHBgs
{ ///xx/weblogic60b2_win.exe t +CU
try{ n.P$E
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Ye>+
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); )$2h:dw_
SiteFileFetch fileFetch = new SiteFileFetch(bean); g%4=T~
fileFetch.start(); lgHzI(
} . vea[
catch(Exception e){e.printStackTrace ();} jwwst\f
eN<?rVZl
IF?
} $')Uie<!8
#N\<(SD/
#q?:Act
public static void main(String[] args) HuD~(CI.
{ *NIhYg6
new TestMethod(); xT+@0?|F
} [{+ZQd
} #Z_f/@b
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