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)); #>8T*B
} y(bsCsV&
for(int i=0;i<nEndPos.length-1;i++) O)`fvpVU
{ CQdBf3q
nEndPos = nStartPos[i+1]; x*.Ye5Jb
} j2|XDOf
nEndPos[nEndPos.length-1] = nFileLength; "~u_\STn <
} ~~PgF"v
} :GQUM6
N-[n\}'
'_B_&is
//启动子线程 >']+OrQH
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 6W5d7`A
for(int i=0;i<nStartPos.length;i++) 9Z&?R++?
{ KNy`Lj)VPY
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ajW[eyX
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), nV'3sUvR#
nStartPos,nEndPos,i); [#p&D~Du&
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); FbveI4
fileSplitterFetch.start(); /H')~!Yz
} 2Ok?@ZdjA{
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), mc?';dEG
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); a`#S|'oatC
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 0pD W _
nEndPos = " + nFileLength); 1h2H1gy5I3
// fileSplitterFetch[nPos.length-1].start(); Qh\YR\O
m$,,YKhh
Rab#7Q16Q8
//等待子线程结束 '9qn*H`'
//int count = 0; 2G?$X?
//是否结束while循环 Vu}806kB
boolean breakWhile = false; 7Yuk
@7-=zt+f
[4p=X=B
while(!bStop) (Akd8}nf~
{ `)6>nPr7P
write_nPos(); ?cJY B)
Utility.sleep(500); ~z5@V5z
breakWhile = true; F) ?o,
\/!ZA[D|E\
<yZP|_
for(int i=0;i<nStartPos.length;i++) <"?*zx&
{ qU#$2
if(!fileSplitterFetch.bDownOver) GR<c=
{ AM'gnP>
breakWhile = false; ! ao6e
break; ~ FGe~
} 5:UyUB
} Km,*)X.-5
if(breakWhile) W2`.RF^
break; Zd[OWF
nTs/Q V
i2*d+?Er
//count++; V$(/0mQV(
//if(count>4) ,;%yf?
// siteStop(); iX%[YQ |
} [EgW/\35
g5y;?fqJ
UFe(4]^
System.err.println("文件下载结束！"); [Eu];
} #|Oj]bd(=
catch(Exception e){e.printStackTrace ();} nd:E9:
} 4}i*cB`
H-(q#?:
P/MM UmO
//获得文件长度 ]*3:DU
public long getFileSize() sK&,):"]R
{ X"j>=DEX
int nFileLength = -1; JS!*2*Wr
try{ SauH>
URL url = new URL(siteInfoBean.getSSiteURL()); dv, C6t2
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ?g3 ]~;#
httpConnection.setRequestProperty("User-Agent","NetFox"); P? (vW&B
3;-^YG
(bv,02
int responseCode=httpConnection.getResponseCode(); hL!QLiF:
if(responseCode>=400) L,?/'!xV
{ tiYOMA
processErrorCode(responseCode); A2NF<ZsD
return -2; //-2 represent access is error -f?Ah
} ^,TTwLy-t
b{M}5~e=B
<'+ %\
String sHeader; +{$QAjW(/
H-I{-Fm
~zF2`.
for(int i=1;;i++) , ECLqs%
{ oq$w4D0Z
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); (e9fm|n!)|
//Utility.log(in.readLine()); +?[BU<X6u
sHeader=httpConnection.getHeaderFieldKey(i); f8'MP9Lv
if(sHeader!=null) .et ^4V3
{ KzphNHd
if(sHeader.equals("Content-Length")) ``u:lL
{ DI1(`y
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); __I/F6{ 9V
break; ^:u?ye;
} *5OCqU+g
} Cqxv"NN
else +@<KC
break; JYm7@gx
} ghAi{@s$)
} Hx2En:^Gf
catch(IOException e){e.printStackTrace ();} I%"'*7U
catch(Exception e){e.printStackTrace ();} eEl.. y
T5|c$doQ
a}gkT]
Utility.log(nFileLength); 8;8c"'Mn
q'G,!];qL
\NK-L."[
return nFileLength; Y]N,.pv=
} hat>kXm2K
`uo,__y
;AIc?Cg
//保存下载信息（文件指针位置） y&oNv xG-
private void write_nPos() tmJgm5v
{ c|AtBgvf
try{ WKl+{e
output = new DataOutputStream(new FileOutputStream(tmpFile)); TWd;EnNM
output.writeInt(nStartPos.length); g=l:cVr8y
for(int i=0;i<nStartPos.length;i++) XiQkrZ
{ QTmZ(>z
// output.writeLong(nPos); yz\c5
output.writeLong(fileSplitterFetch.nStartPos); !kL> ,O>/
output.writeLong(fileSplitterFetch.nEndPos); < g|Z}Y
} 2p!"p`b~
output.close(); W^\d^)
} `t(D!
catch(IOException e){e.printStackTrace ();} +fNvNbtA
catch(Exception e){e.printStackTrace ();} Jblj^n?Bm
} wRtZ`o
,v9f~qh
<>Y?vC
//读取保存的下载信息（文件指针位置） &dR=?bz-A
private void read_nPos() iv&v8;B
{ q,%:h`t\
try{ ?_g1*@pA
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); hhI)' $
int nCount = input.readInt(); A],ooiq<
nStartPos = new long[nCount]; }uY!(4Rw
nEndPos = new long[nCount]; 4!#a3=_
for(int i=0;i<nStartPos.length;i++) p$E8Bn%[
{ } JiSmi6o
nStartPos = input.readLong(); qO@@8/l
nEndPos = input.readLong(); bKDA!R2
} ][;G=oCT
input.close(); Kw5Lhc1V
} 57,dw-|xi
catch(IOException e){e.printStackTrace ();} a%vrt)Gx
catch(Exception e){e.printStackTrace ();} ]N{0:Va@D
} Anm=*;*M`
%|"g/2sF[G
sJG5/w
private void processErrorCode(int nErrorCode) NbRn*nb/T
{ *G5c|Y
System.err.println("Error Code : " + nErrorCode); )ChqATKg
} Ts$@s^S]
E=]4ctK
[KJ q
//停止文件下载 q,>?QBct*
public void siteStop() Vz=auM1xZ
{ eH%RNtP`
bStop = true; TX [%(ft
for(int i=0;i<nStartPos.length;i++) qMYe{{r
fileSplitterFetch.splitterStop(); 8,"yNq
Q{g;J`Z)p
Tr&M~Lgb)
} 2aN<w'pA
} U/l?>lOD\
//负责部分文件的抓取 BX+.0M
**FileSplitterFetch.java _-TA{21)
*/ @A<PkpNL
package NetFox; tw=oH9c80
lfZ04M{2
,XkGe
import java.io.*; 5ETip'<KT6
import java.net.*; @`36ku
4qi[r)G
_aWl]I){5
public class FileSplitterFetch extends Thread { ;)AfB#:d
0\9K3
5ExDB6Bx@y
String sURL; //File URL PxFWJ?=
long nStartPos; //File Snippet Start Position ~]C%/gEh
long nEndPos; //File Snippet End Position *J|(jdu7
int nThreadID; //Thread's ID <[:o !$
boolean bDownOver = false; //Downing is over ?:{sH#ua
boolean bStop = false; //Stop identical RDqFL.-S
FileAccessI fileAccessI = null; //File Access interface . #lsic8]
:Y,BdU
/Ci*Az P
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException Kf tgOG f
{ 8T)&`dM6P~
this.sURL = sURL; T:]L/wCj
this.nStartPos = nStart; BQH}6ueZ
this.nEndPos = nEnd; F[ ajOb8
nThreadID = id; "XgmuSQ!
fileAccessI = new FileAccessI(sName,nStartPos);//定位 _5 ^I.5Z3
} 'B5^P
?S$i?\Qh
l:#-d.z#
public void run() XQ%4L-rhN
{ YKmsQ(q`N
while(nStartPos < nEndPos && !bStop) %WTEv?I{Ga
{ d[p;T\?"
L|-98]8>
Q6gt+FKU9
try{ s~I6SA&i
URL url = new URL(sURL); bHLT}x/Gw
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); G;NF5`*4mc
httpConnection.setRequestProperty("User-Agent","NetFox"); dovZ#D@Q
String sProperty = "bytes="+nStartPos+"-"; DGW+>\G
httpConnection.setRequestProperty("RANGE",sProperty); &8.NT~"Gg
Utility.log(sProperty); 05yZad*
)SryDRT
xv{O^Ie+S
InputStream input = httpConnection.getInputStream(); Yim<>. !
//logResponseHead(httpConnection); 7>iU1zy
[/s&K{+c
3pf[M{dG
byte[] b = new byte[1024]; @%k}FL=:t(
int nRead; HK\~Qnq
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ~qe%Yq
{ \^I>Q_LU
nStartPos += fileAccessI.write(b,0,nRead); -7J|l
//if(nThreadID == 1) ^7zu<lX
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); }Sy=My89r
} n -(
Hbv6_H
qW:HNEiir
Utility.log("Thread " + nThreadID + " is over!"); kmzH'wktt
bDownOver = true; 6T 8!xyi-+
//nPos = fileAccessI.write (b,0,nRead); DCqY|4Qc
} -*5Rnx|Y{
catch(Exception e){e.printStackTrace ();} T\~x.aH`^
} bR@p<;G|
} =X.LA%Sf=u
Z{&cuo.@<]
T~QJO0
//打印回应的头信息 241*!
public void logResponseHead(HttpURLConnection con) @(r/dZc
{ hI9
for(int i=1;;i++) __mF?m
{ =UyLk-P w
String header=con.getHeaderFieldKey(i); jw-0M1B
if(header!=null) PkI:*\R
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 87hq{tTs]
Utility.log(header+" : "+con.getHeaderField(header)); &0f5:M{P
else McB[|PmC
break; {G?N E
} 9tF9T\jW
} #o1=:PQaC
: ]C~gc
RKPO#qju\F
public void splitterStop() %iV^S!e
{ boDt`2=
bStop = true; %^RN#_ro(3
} ]_N|L|]M
ER,1(1]N
vWAL^?HUP
} I`NjqyTW
#g6.Glz3
U&O: _>~
/* e7wSOs
**FileAccess.java P.gb1$7<
*//文件访问(定位，写) ]U"94S U:)
package NetFox; Gea\,{E9xA
import java.io.*; 13taFVdU
$Xq!L
Ub6jxib
public class FileAccessI implements Serializable{ iLSr*` o
(o`{uj{!
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 6j ~#[
RandomAccessFile oSavedFile; 21"1NJzP
long nPos; eJg8,7WC
%c4Hse#Y
p5G?N(l
public FileAccessI() throws IOException `V##Y
{ .V,@k7U,V
this("",0); FSND>\>
} p,#o<W
P&f7@MOV.P
J{Q|mD=
public FileAccessI(String sName,long nPos) throws IOException #\=FO>
{ % >=!p
oSavedFile = new RandomAccessFile(sName,"rw"); B {>7-0
this.nPos = nPos; ZHa"isl$e
oSavedFile.seek(nPos); <Y}R#o1Z
} E>K!Vrh-L
V:joFRH9
{;2PL^i
public synchronized int write(byte[] b,int nStart,int nLen) -fDnA4;
{ hIT+gnhh
int n = -1; >7 ="8
try{ i{`:(F5*
oSavedFile.write(b,nStart,nLen); v/_
n = nLen; wRVUu)
} uA<n
catch(IOException e) ez|)ph7
{ ]9^sa-8
e.printStackTrace (); ueUuJxq)
} }~L.qG
E 7{U|\
H*}y^)x
return n; ~A\GT$
} ;0Tx-8l
uLV#SQ=bZN
`x*Pof!Io
} YuO.yh_
tS6qWtE
\2h!aRWR
/* F1yqxWHeo
**SiteInfoBean.java a^I\ /&aw'
*/ aht[4(XH5
package NetFox; cz8T
p^w;kN
lNYt`xp
public class SiteInfoBean { JJN.ugT}1
M<v%CawS
t7aefV&_,
private String sSiteURL; //Site's URL HMNLa*CL'
private String sFilePath; //Saved File's Path 2fL;-\!y(
private String sFileName; //Saved File's Name H*PSR
private int nSplitter; //Count of Splited Downloading File Y^wW2-,m
8)_XJ"9)G
bE !GJZ
public SiteInfoBean() _z|65H
{//nSplitter的缺省值为5 JkbQyn
//default value of nSplitter is 5 (,0(
this("","","",5); GBPo8L"9
} FOE4>zE
;@oN s-
YIG~MP
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) xqu}cz
{ K &N
sSiteURL= sURL; (5-FVp fb
sFilePath = sPath; 3EPv"f^V
sFileName = sName; ]>5/PD,wWy
this.nSplitter = nSpiltter; sYI-5D]
H&-zZc4\
X}Ai-D
} s Z].8.
?67Y-\}
9sYMSc~Bm
public String getSSiteURL() z7fp#>uw
{ I 7{T
return sSiteURL; #Lh;CSS
} *XIF)Q=<>
kaVxT_
ivJ@=pd)B
public void setSSiteURL(String value) |v3T!
{ vdc\R?
sSiteURL = value; ek*rp`y]
} *`5.|{<j{
AP?R"%
D2Kp|F;
public String getSFilePath() tEvut=k'
{ *0Skd
return sFilePath; 12b(A+M
} r@H /kD
"#2a8#
nFHUy9q
public void setSFilePath(String value) ^ B fC
{ )q8pk2
sFilePath = value; K0|FY=#2y
} 2*laAB
#A JDWelD
3u+T~g0^
public String getSFileName() U:0mp"
{ V^bwXr4f
return sFileName; 6 ob@[ @
} p>v$FiV2N
Nk? ^1n$
g}k`o!q
public void setSFileName(String value) 6]WAUK%h
{ |\pj;XU
sFileName = value; h+g_rvIG*
} t%/&c::(6
JcsHt;
Z&+ g;(g
public int getNSplitter() /[ 5gX^A
{ On9A U:\
return nSplitter; 6*78cg Io
} FXG]LoP
"c%0P"u
FrfM3x6UM
public void setNSplitter(int nCount) gwuI-d^
{ d;Ym=YHJtn
nSplitter = nCount; :^6y7&o[
} c_$=-Khk
} %rL.|q9
aFX=C>M
'T*&'RQr
/* dVtG/0
**Utility.java pZ.ecZe/
*/ qd ~BnR$=
package NetFox; ;#W2|'HD
5}l[>lF
u5`u>.!
public class Utility { Q%`@0#"]Sv
t6"%3#s
r= `Jn6@
public Utility() Cn34b_Sbd
{ |.: q
^eY!U%.
v!~fs)cdE|
} MS~(D.@ZS
!GjQPAW
//线程睡眠 'x#~'v*
public static void sleep(int nSecond) :'X&bn
{ >C>.\
try{ ?=Z?6fw
Thread.sleep(nSecond); C`hU]
} ~d.Y&b
catch(Exception e) {3mRq"e
{ EHJ.T~X
e.printStackTrace (); ( Y[Q,
} #jvtUS\
} hR?{3d#x2
Mq156TL
//日志 hn GZ=
public static void log(String sMsg) e'NJnPO
{ ~w+c8c8pW
System.err.println(sMsg); AlaW=leTe
} cA?W7D
AofKw
SwGx?U
public static void log(int sMsg) Mk 6(UXY
{ Qz1E 2yJ
System.err.println(sMsg); pI\]6U
} ?(1y
} `g=J%p
|mfvr*7
6Pl<'3&
/* MAR'y8I
**TestMethod.java Gx/Oi)&/
*/ ASA,{w]
package NetFox; m.rmM`
+Mb.:_7'
Rh{f5-
public class TestMethod { eF$x1|
&'`g#N
F v2-(
public TestMethod() "%w u2%i
{ ///xx/weblogic60b2_win.exe +{.WQA}z\
try{ P/eeC"
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); BL}\D;+t
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); )qw&%sO +
SiteFileFetch fileFetch = new SiteFileFetch(bean); CY5Z{qiX
fileFetch.start(); ITI)soa~
} A}9`S6@@
catch(Exception e){e.printStackTrace ();} xJ]\+ 50
U?Zq6_M&
}o(-=lF
} PJ%C N(0
4xje$/_d
WSB0~+
public static void main(String[] args) sY&IquK^
{ B~ GbF*j
new TestMethod(); .*Y
} *i%.;Z"
} %5n_ p^xp
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