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)); !rnjmc
} ]_s3<&R
for(int i=0;i<nEndPos.length-1;i++) SXL3>-Z E
{ [ws _ g,/
nEndPos = nStartPos[i+1]; o 4F'z
} !Tnjha*
nEndPos[nEndPos.length-1] = nFileLength; tYjG8P#
} u BEwYQB
} ^'X I%fEf
#NM)
B!RfPk1B<*
//启动子线程 -`L`kL<
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 't<iB&wgF
for(int i=0;i<nStartPos.length;i++) |1@O>GG
{ ]Uv,}W
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), S!?T0c?>
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ^to*ET{0
nStartPos,nEndPos,i); u]*7",R uU
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2C S9v
fileSplitterFetch.start(); @ m`C%7<
} <9@n/
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), XM]m%I
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); rNN>tpZ}
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", "c%wq0
nEndPos = " + nFileLength); c9/w{}F
// fileSplitterFetch[nPos.length-1].start(); kz=ho~ @
pBqf+}g4
DGFSD Py[
//等待子线程结束 ZF7@b/-me
//int count = 0; S`-I-VS=L
//是否结束while循环 mE~WE+lw9
boolean breakWhile = false; +/B
cK$yr)7
A{_CU-,
while(!bStop) |V34;}\4
{ 9^*RK6
write_nPos(); N'b GL%
Utility.sleep(500); uda++^y:
breakWhile = true; *;Kp"j
dS1HA>c)O
p3P8@M
for(int i=0;i<nStartPos.length;i++) 6J;!p/C8E
{ <K)]kf
if(!fileSplitterFetch.bDownOver) wUvE
{ .X!!dx1<
breakWhile = false; R>c>wYt'f
break; y[McdlH m
} "%T~d[M
} 67EGkW?hbt
if(breakWhile) )"TVR{I%B
break; "ku[b\W
q^[t</_N
uyX %&r
//count++; "dpjxH=xO
//if(count>4) x}2nn)fdZ
// siteStop(); x(c+~4:_M
} Ug*B[q/
cyNE}
QGNKQ`~
System.err.println("文件下载结束！"); jI,[(Z>
} &r[f ;|o
catch(Exception e){e.printStackTrace ();} ;Tbo \Wp9
} !$Uo$?gC
S$b)X"h
]I*RuDv}
//获得文件长度 hP:>!KJ
public long getFileSize() Q7x[08TI
{ ";.j[p:gi
int nFileLength = -1; '6zZ`Ll9
try{ -UEi
URL url = new URL(siteInfoBean.getSSiteURL()); GkOk.9Y,5
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); wXQu%F3
httpConnection.setRequestProperty("User-Agent","NetFox"); i?^L",[
3?E7\\/R
]O;*Y{:Y
int responseCode=httpConnection.getResponseCode(); =*fq5v
if(responseCode>=400) \zU<o~gs
{ }wo:1v8J
processErrorCode(responseCode); 0^*,E/}P&
return -2; //-2 represent access is error ,|c;x1|O
} IWYQ67Yj
Kjbk zc1
`NhG|g
String sHeader; Um/l{:S
QP~["%}T
8K2@[TE=5
for(int i=1;;i++) ksq4t
{ 7mSNz.
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); #j7&2L
//Utility.log(in.readLine()); 6!i`\>I]
sHeader=httpConnection.getHeaderFieldKey(i); iq3)}hGo
if(sHeader!=null) O+&;,R:
{ ;):;H?WS|A
if(sHeader.equals("Content-Length")) [+FiD
{ KxErWP%
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 2RZa}
break; xjBY6Ylz
} ok6t| 7sq
} ZeG4z({af
else -pJ\_u/&%`
break; @@@}FV&
} <IIz-6*V
} (J4( Ge
catch(IOException e){e.printStackTrace ();} !>'A2V~F
catch(Exception e){e.printStackTrace ();} P7>\j*U91{
3` IR ^
WS6Qp`c)e
Utility.log(nFileLength); #Ey_.4S
)09ltr0@"
.0,G4k/yv
return nFileLength; j#3IF *"
} .Ao _cx
0B[~j7EGO
%>/&&(BE
//保存下载信息（文件指针位置） 7 2i&-`&4
private void write_nPos() 3\]j4*i!
{ aAP86MHO
try{ fP 3eR>e
output = new DataOutputStream(new FileOutputStream(tmpFile)); Vk`Uz1*
output.writeInt(nStartPos.length); ,f%4xXI
for(int i=0;i<nStartPos.length;i++) ,2U
{ k]AL\) &W
// output.writeLong(nPos); },X.a@:
output.writeLong(fileSplitterFetch.nStartPos); `_.:O,^n^
output.writeLong(fileSplitterFetch.nEndPos); kbvF 9#
} Mk9J~'C_
output.close(); ]w,|WZm
} ;Tk/}Od!VN
catch(IOException e){e.printStackTrace ();} ;9#%E
catch(Exception e){e.printStackTrace ();} 'k}w|gNB
} 'b"7Lzp2
;dfIzi
>bI\pJ
//读取保存的下载信息（文件指针位置） pub?%
private void read_nPos() t(vyi
{ S.>fB7'(?=
try{ GB Vqc!d
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); NZG ^B/
int nCount = input.readInt(); A:4&XRYZY
nStartPos = new long[nCount]; jT]R"U/Q
nEndPos = new long[nCount]; -ert42fN
for(int i=0;i<nStartPos.length;i++) 'xG{q+jj'
{ 7k%!D"6_R
nStartPos = input.readLong(); v.sjWF
nEndPos = input.readLong(); `wIWK7i
} Jw;G_dQ[
input.close(); J..>ApX
} _n(NPFV
catch(IOException e){e.printStackTrace ();} # a 'h,
catch(Exception e){e.printStackTrace ();} '@u/] ra:
} .foM>UOY
z.:{
)>Oip
private void processErrorCode(int nErrorCode) OedL?4
{ H>[1DH#b
System.err.println("Error Code : " + nErrorCode); SQ)$>3>C
} AyKaazm]9
l/_3H\iM
a8-2:8Su
//停止文件下载 -L6 rXQV@j
public void siteStop() o*\kg+8
{ /b20!3
bStop = true; })Rmu."\
for(int i=0;i<nStartPos.length;i++) 8h~v%aZ1
fileSplitterFetch.splitterStop(); 1<^"OjQ
pc5-'; n
N7*JL2Rnq
} UnZ*"%
} -@G|i$!
//负责部分文件的抓取 2s;/*<WM
**FileSplitterFetch.java BSG_),AH
*/ J1Mm,LTO
package NetFox; *"0Yr`)S
t(CdoE,6
Y*O7lZuF%
import java.io.*; <FMW%4
import java.net.*; >\8Bu#&s4
yyrCO"eh
O%A:2Y79
public class FileSplitterFetch extends Thread { WKqNJN C
=V_}z3b
X}_}`wIn
String sURL; //File URL '@wYr|s4
long nStartPos; //File Snippet Start Position {.z2n>1J{T
long nEndPos; //File Snippet End Position tz&=v,_jc
int nThreadID; //Thread's ID m1VyYG
boolean bDownOver = false; //Downing is over ._=Pa)T
boolean bStop = false; //Stop identical NyJU?^f&v
FileAccessI fileAccessI = null; //File Access interface Qwk
<[?oP[ j
?.IT!M}DR
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 75@){ :
{ ME1lQ7E4B
this.sURL = sURL; ss%ahs
this.nStartPos = nStart; 2<yi8O\
this.nEndPos = nEnd; DL|,:2`
nThreadID = id; >z h
fileAccessI = new FileAccessI(sName,nStartPos);//定位 S,lJ&Rsu
} v@LK3S/!3
VCcLS3
22`W*e@6h
public void run() OTL=(k
{ PLKp<kg
while(nStartPos < nEndPos && !bStop) d[w'j/{
{ ={W;8BUV%^
O!lZ%j@%
._~_OVU
try{ /lx\9S|
URL url = new URL(sURL); 4VSlgoz
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); x$J1%K*
httpConnection.setRequestProperty("User-Agent","NetFox"); c#$B;?
String sProperty = "bytes="+nStartPos+"-"; ]=2Ba<)m
httpConnection.setRequestProperty("RANGE",sProperty); ~{0:`)2FQ
Utility.log(sProperty); CK 3]]{
xSs);XO,
uo_Y"QiKEH
InputStream input = httpConnection.getInputStream(); rC14X}X6
//logResponseHead(httpConnection); \s<{V7tq
m(s(2wq"f
Q$Ga.fI
byte[] b = new byte[1024]; yaMNt}y-q
int nRead; #Bg88!-4
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) U>IllNd
{ ePq(:ih
nStartPos += fileAccessI.write(b,0,nRead); e ,/I}W
//if(nThreadID == 1) 9s6@AJf
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2xhwi.u
} sHyhR:
GRB/N1=
wV+ W(
Utility.log("Thread " + nThreadID + " is over!"); Jor>YB`X
bDownOver = true; ,3.E]_3xX
//nPos = fileAccessI.write (b,0,nRead); oN)l/"%C7/
} WM.JoQ
catch(Exception e){e.printStackTrace ();} ^ ~:f02[D
} ;o8C(5xE|
} WW{5[;LYiB
gV$j ]
%%`Nq&'
//打印回应的头信息 @*]l.F
public void logResponseHead(HttpURLConnection con) }&I\a
{ ];Z)=y,vM
for(int i=1;;i++) ;&q}G1
{ VLC<ju!
String header=con.getHeaderFieldKey(i); +>/ariRr
if(header!=null) p~6/+ap
//responseHeaders.put(header,httpConnection.getHeaderField(header)); (MY#;v\AYE
Utility.log(header+" : "+con.getHeaderField(header)); z}.y ?#
else 1 0lvhzU
break; k__iJsk
} mE'y$5ZxY
} lYmqFd~p
f uQbDb&
<`k\kZM
public void splitterStop() 26PUO$&b.
{ 4z#{nZG
bStop = true; 11[[HkX@
} 59!yz'feF
,yus44w[
T]-yTsto
} T]Z|Wq`bot
)b`Xc+{>
k4fc5P
/* to,DN2rN
**FileAccess.java w`=_|4wFw
*//文件访问(定位，写) Gdmh#pv
package NetFox; &[:MTK?x!
import java.io.*; ]E'BFon
vw5f.8T;w
A'r 3%mC
public class FileAccessI implements Serializable{ DX GClH
<k?ofE1o
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 oJa6)+b(3
RandomAccessFile oSavedFile; s3qWTdM
long nPos; CT,caa
OzY55
D,q=?~
public FileAccessI() throws IOException .w2QiJ
{ ie|I*;#
this("",0); )OQhtxK
} H,,-;tN?
kms&o=^
#:C;VAAp
public FileAccessI(String sName,long nPos) throws IOException Q|QVm,m
{ io:g]g
oSavedFile = new RandomAccessFile(sName,"rw"); S^q)DuF5!
this.nPos = nPos; NbOeF7cq+
oSavedFile.seek(nPos); [ []'U'
} y_O[r1MF
_svEPHU
$jT&]p
public synchronized int write(byte[] b,int nStart,int nLen) wKF #8Y
{ J-*&&
int n = -1; Td#D\d\R
try{ jv$Y]nf
oSavedFile.write(b,nStart,nLen); Q#C;4)e
n = nLen; M|!^ #!a(
} dmh6o *
catch(IOException e) 1d/-SxhZ
{ 0dS}pd">k
e.printStackTrace (); 9~+A<X]Hd
} kN3T/96
l`lo5:w
/ hUuQDJ
return n; /H#- \r&r
} @L^Fz$Sx
(vte8uQe
hUirvDvX
} Bvzu{B%
6#~"~WfPQ
tX;00g;U.
/* #Mo`l/Cwp
**SiteInfoBean.java Ol,;BZHc\
*/ cBf9-k
package NetFox; p.KX[I
^l1tQnj)7
n^|;J*rD
public class SiteInfoBean { ~;St,Fw<<
`@GqD
7q bGA K
private String sSiteURL; //Site's URL WqN=D5
private String sFilePath; //Saved File's Path |\Nj
private String sFileName; //Saved File's Name $ tf;\R
private int nSplitter; //Count of Splited Downloading File H+ra w/"
*]2LN$
Z=%+U _,
public SiteInfoBean() d_9Fc"C~
{//nSplitter的缺省值为5 MLg<YL
//default value of nSplitter is 5 ~82[pY
this("","","",5); 8f>=.O*)
} ?]gZg[
"sLdkd}dj
^_4TDC~h
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ^q6H =Dl
{ fs4pAB#F
sSiteURL= sURL; d7N;Fa3yL
sFilePath = sPath; 'G6TSl
sFileName = sName; ${'gyD
this.nSplitter = nSpiltter; $mm =$.
}_XW?^/8
R_h(Z{d
} 1"46OCu{
g!n1]- 1
Cus=UzL
public String getSSiteURL() 8)/i\=N3;
{ J<DV7zV
return sSiteURL; Cw?AP6f%
} FD(zj^*
|Hn[XRsf
}yqRz6=YB
public void setSSiteURL(String value) P Y +~,T2
{ mOwgk7s[J
sSiteURL = value; a:@9GmtV&
} )hk=wu6
g$VcT\X
pH#&B_S6z=
public String getSFilePath() O;[PEV~
{ =1^a/
return sFilePath; IyG5Rj2
} L*tXy>&b.
nzy =0Ox[
t )Z2"_5
public void setSFilePath(String value) N&NOh|YS
{ 'R_U,9y`
sFilePath = value; Ga f/0/|
} v,vTRrpK
fEs957$
9BI5qHEp
public String getSFileName() M)Rp+uQ
{ bI[!y#_z4
return sFileName; fLI@;*hL0
} p@i U}SUaE
>0 !J]gK
w:FH2*
public void setSFileName(String value) )I]E%ut{4,
{ T.ub!,Y
sFileName = value; P},S[GaZ
} e"r'z n
?y<n^`
=@pm-rI|-
public int getNSplitter() (/YC\x?
{ b("CvD8
return nSplitter; dMGu9k~u
} t{~"vD9Am
w2]1ftY
b]RCe^E1
public void setNSplitter(int nCount) ?P`wLS^;
{ _Fl]zs<
nSplitter = nCount; 6}iIK,Om
} S-2xe?sb
} %c^]Rdl
|<y[gj4`T/
{w!}:8p
/* N)poe2[
**Utility.java F!]UaEmV
*/ f~Kln^
package NetFox; QQ2xNNF[
5\|[)~b
w-/bLg[L?$
public class Utility { ULU ]k#
IR/0gP
Ce5 }+A}
public Utility() ?\vJ8H[bD
{ AZl=w`;/O%
uU5:,Wy+dg
B|extWwu
} ybS7uo
@.0jC=!l
//线程睡眠 ?WAlW,H>
public static void sleep(int nSecond) O)9T|, U
{ 8 6L&u:o:
try{ 6 Dg[b
Thread.sleep(nSecond); TP^.]IO-
} vO0ql
catch(Exception e) W 8E<P y
{ 55$by.rf?
e.printStackTrace (); }WCz*v1Wq
} GuDus2#+
} JpuW !I
MH !CzV&
//日志 a?JU(
public static void log(String sMsg) :=i0$k<E/
{ t#P)KcWOt
System.err.println(sMsg); 2iH,U
} "jeJV,%
tS!~>X
@'}X&TN<a
public static void log(int sMsg) .Zwn{SMtu
{ `E|IMUB~
System.err.println(sMsg); <c\aZ9+V
} s#d# *pgzh
} XD|&{/O
zM@iG]?kc
^)fB "!s
/* wPc,FH+y
**TestMethod.java Ab(bvS8r$
*/ . }=;]=
package NetFox; Q`//HOM,
Yb?#vpI
w1KQ9H*
public class TestMethod { ED$gnFa3I
>Y\4v}-
'.dW>7
public TestMethod() ar^`r!ABEh
{ ///xx/weblogic60b2_win.exe +'KM~c?]
try{ HFDg@@
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); D^TKv;%d
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); QWxQD'L'
SiteFileFetch fileFetch = new SiteFileFetch(bean); ?.Kl/8ml
fileFetch.start(); 4o=G) KO{
} 8WyG49eic
catch(Exception e){e.printStackTrace ();} /z'j:~`E
MRC5c:(
?_^9e
} |aVv Lz
_ Po9pZ
HwGtLeB"
public static void main(String[] args) AVJF[t,
{ m0#hG x
new TestMethod(); Zg'[.wov
} )l"0:1Ig
} \UC4ai2MK
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