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)); 4d6% t2
} ;:^ Lv
for(int i=0;i<nEndPos.length-1;i++) 1bDJ}M~]z
{ \SzGzCJ
nEndPos = nStartPos[i+1]; t_Z _!Qy
} >~>{;Wq(p+
nEndPos[nEndPos.length-1] = nFileLength; dWIZ37w+D
} |3"NwM>
} $OT}`Te~
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<q1'Li)_R
//启动子线程 k{qLkcOg=
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; \ j x0ZHR
for(int i=0;i<nStartPos.length;i++) I<9n(rA
{ ){jqfkL
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), D;J|eC>^
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Vy&f"4~
nStartPos,nEndPos,i); G$S1#F -
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); cC'^T6
fileSplitterFetch.start(); ->Q`'@'|P
} B[Ix?V4yy
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), y 2cL2c$BT
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 9DY|Sa]#=
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", rt,0j/o.1
nEndPos = " + nFileLength); QQSH +
// fileSplitterFetch[nPos.length-1].start(); g8rp|MOH
% Mw'e/?
3a/[."W u
//等待子线程结束 L F8Pb;I
//int count = 0; '?z9,oW{
//是否结束while循环 KuU3DTS85Z
boolean breakWhile = false; $8EV,9^U
(v|ixa
fuQ4rt[i
while(!bStop) .Kg|f~InO
{ \}U[}5Pk&
write_nPos(); 8H&_,;
Utility.sleep(500); 'E@2I9Kj
breakWhile = true; 3j]UEA^
.jLMl*6%:
d*]Dv,#X
for(int i=0;i<nStartPos.length;i++) [0d-CEp[
{ %H 8A=
if(!fileSplitterFetch.bDownOver) 9k(*?!\;
{ s$js5 ou
breakWhile = false; N)9pz?*V
break; W\nHX I
} }C_G0'"F
} .vCY%0oE
if(breakWhile) R-=_z6<
break; R>/QARX
=)mXCA^
-d$8WSI8
//count++; Dq0-Kf,^
//if(count>4) TBoM{s=.
// siteStop(); KK&<Vw|O\
} L?Kz P.(t+
BfD,z
@Fm{6^
System.err.println("文件下载结束！"); {bAWc.
} R@)'Bs
catch(Exception e){e.printStackTrace ();} f_Wkg)g
} d,GtH)(s
$|`t9-EA/
5Z4(J?n
//获得文件长度 PfwI@%2
public long getFileSize() wGov|[X
{ WHpUjyBP
int nFileLength = -1; _IQU<Za
try{ 0%GqCg
URL url = new URL(siteInfoBean.getSSiteURL()); 0?J|C6XM#4
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); PV,kYM6
httpConnection.setRequestProperty("User-Agent","NetFox"); :Y}Y&mA4
STFQ";z$
uQ)JC7b\
int responseCode=httpConnection.getResponseCode(); Zq\RNZ}
if(responseCode>=400) 0Y38T)k
{ [9db=$v8$
processErrorCode(responseCode); '[M^f+H|
return -2; //-2 represent access is error L&!g33J&
} #f|NM7
ex@,F,u>o
0i5T] )r
String sHeader; KG4#BY&^
|dB1R%
]2aYi9)
for(int i=1;;i++) Q}=W>|aE.
{ ^.Ih,@N6
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); niBjq#bJi
//Utility.log(in.readLine()); }ZM*[j
sHeader=httpConnection.getHeaderFieldKey(i); aUIc=Z
if(sHeader!=null) NSxPN:
{ </+%R"`
if(sHeader.equals("Content-Length")) XL.CJ5y>
{ ]@ Sc}
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 3x(MvW30Lg
break; ; $ ?jR c
} Bp$+ F/
} H.l,%x&K
else n ]6 0
break; /BjGAa(
} NrI5uC7
} k8x&aH
catch(IOException e){e.printStackTrace ();} <<W.x)#:
catch(Exception e){e.printStackTrace ();} <*r<+S
"`W1yk5x
z[|PsC3i:
Utility.log(nFileLength); K9I,Q$&xX
g+KzlS[6
_r?;lnWx@
return nFileLength; yhkQFB%gv
} e`Zg7CaDd
Y)4Nydq
$*v20
//保存下载信息（文件指针位置） QIMv9;
private void write_nPos() OJ_2z|f<
{ uuUVE/^V'
try{ =@Nv:1:r
output = new DataOutputStream(new FileOutputStream(tmpFile)); 6JFDRsX>)?
output.writeInt(nStartPos.length); |jaY[_.@
for(int i=0;i<nStartPos.length;i++) D 5r
{ kX ,FQG>
// output.writeLong(nPos); 'd.@4 9
output.writeLong(fileSplitterFetch.nStartPos); j]?0}Z*
output.writeLong(fileSplitterFetch.nEndPos); 5KH'|z
} !^w\$cw&
output.close(); _!^FW%
} H+#wj|,+\
catch(IOException e){e.printStackTrace ();} Kf?{GNE7
catch(Exception e){e.printStackTrace ();} ^< /vbF
} qnfRN'
'Rh>w=wB'
Obc3^pV&
//读取保存的下载信息（文件指针位置） *ckrn>E{h
private void read_nPos() BL5
{ x&fCe{5
try{ ot+~|Dl
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ~Yz/t
int nCount = input.readInt(); W &wDH
nStartPos = new long[nCount]; 5B.??;xtaV
nEndPos = new long[nCount]; qp_ `Fj:
for(int i=0;i<nStartPos.length;i++) ]xLb )Z
{ v3JIUdU=P
nStartPos = input.readLong(); q\HBAry
nEndPos = input.readLong(); 0^lL,rC
} 6-X?uaY)os
input.close(); MW[ 4^
} Y&Lk4
catch(IOException e){e.printStackTrace ();} cf!k 9x9Z
catch(Exception e){e.printStackTrace ();} B*iz+"H
} >(6\ C
k`~br249
.x$T al
private void processErrorCode(int nErrorCode) GK+\-U)v
{ ^oB1 &G
System.err.println("Error Code : " + nErrorCode); ;)]zv\fC
} 8Bt-
}7z+
pbvEIa-Y4
//停止文件下载 c^WBB$v
public void siteStop() P"~T*Qq-R
{ wXZY5-h4
bStop = true; RH4n0=2
for(int i=0;i<nStartPos.length;i++) f EiEfu
fileSplitterFetch.splitterStop(); eC`f8=V
t RyGxqiG
<r`Jn49
} `LU,uz
} ,k!f`
//负责部分文件的抓取 RTY4%6]O
**FileSplitterFetch.java zwrZ^
*/ e CUcE(
package NetFox; : 8<^rP
<0 idG
y]Tn#4 ,/
import java.io.*; Q4:r$ &
import java.net.*; QGj5\{E_
o5x^"#
E d/O\v@
public class FileSplitterFetch extends Thread { TXl9c6
)tch>.EQ_
ujqktrhuLb
String sURL; //File URL R.`J"J0/~
long nStartPos; //File Snippet Start Position |3@Pt>Ikl
long nEndPos; //File Snippet End Position k$_]b0D{4
int nThreadID; //Thread's ID {$:13AnK
boolean bDownOver = false; //Downing is over Y1+lk^
boolean bStop = false; //Stop identical km^+ mK
FileAccessI fileAccessI = null; //File Access interface u.Yb#?
]~Qkg+>'&
+`3ZH9
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException @}!$NI8
{ aKtTx~$@
this.sURL = sURL; {/!Gh\i
this.nStartPos = nStart; OSIp
this.nEndPos = nEnd; Cjk AQ(9
nThreadID = id; '+zsj0!A
fileAccessI = new FileAccessI(sName,nStartPos);//定位 c6)zx b
} 6l7a9IJ
]m>MB )9
&L~rq)r/&
public void run() ,peE'
{ g(H3arb&
while(nStartPos < nEndPos && !bStop) }rZ=j6Z
{ 8!>pFVNJf
4O^1gw
?EAqv]
try{ M0 8Y
URL url = new URL(sURL); e'&{KD,-T
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); o2jB~}VMl
httpConnection.setRequestProperty("User-Agent","NetFox"); }>U03aa!
String sProperty = "bytes="+nStartPos+"-"; 9<mj@bI$
httpConnection.setRequestProperty("RANGE",sProperty); nCB3d[/B
Utility.log(sProperty); [rsAY&.
a<.@+sj{
`BD`pa7.%
InputStream input = httpConnection.getInputStream(); R"([Y#>m
//logResponseHead(httpConnection); Lr:K0A.Ch
M6!brj\[|
b] V=wZ o
byte[] b = new byte[1024]; V=~dgy~@
int nRead; Cz)D3Df^
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) >,vuC4v-
{ RA/yvr
nStartPos += fileAccessI.write(b,0,nRead); xRN$cZC
//if(nThreadID == 1) -',Y;0b%
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Z5A<TC/:
} -<=<T@,
kw'D2692
cgOoQP/#
Utility.log("Thread " + nThreadID + " is over!"); UUq9UV-h
bDownOver = true; t+ ]+Gn
//nPos = fileAccessI.write (b,0,nRead); XZGyhX7
} |\t_I~de
catch(Exception e){e.printStackTrace ();} g*M3;G
} oR)7 \;g
} "o^zOU
>0oc=9H8
!ZW0yCwLQ
//打印回应的头信息 v%^H9aK_
public void logResponseHead(HttpURLConnection con) jo~vOu
{ ntejFy9_
for(int i=1;;i++) [&:oS35O
{ /o2eKx
String header=con.getHeaderFieldKey(i); ,e,{6Sg6gl
if(header!=null) R?Qou!*]
//responseHeaders.put(header,httpConnection.getHeaderField(header)); N}=-+E|
Utility.log(header+" : "+con.getHeaderField(header)); ZHJzh\?
else x!+a,+G
break; I j /J
} Fz% n!d
} Y'T#
",m5}mk:4
-E1}mL}I`
public void splitterStop() ;D:v@I$I
{ 4]GyuY
bStop = true; hGeRM4zVZZ
} K2QD&!4/T2
Sy_M!`B
sMx\WTyz
} jX%Q
;z68`P-
_u0dt) $
/* [g? NU]
**FileAccess.java q3:tZoeXV
*//文件访问(定位，写) &}r932
package NetFox; 5eYCnc9
import java.io.*; I zT%Kq
!v-(O"a
R~i<*
public class FileAccessI implements Serializable{ Z&%61jGK
w%ForDB>P
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 d={}a,3?
RandomAccessFile oSavedFile; L2$%h1
long nPos; &}]Wbk4:
]O[f#lG
]mp.KvB
public FileAccessI() throws IOException mXr)lA
{ a4wh-35/
this("",0); w*+rBp,f
} Q_dFZ
#E#70vWp\O
4&\m!s
public FileAccessI(String sName,long nPos) throws IOException TzOf&cs/r
{ 4l|Am3vzX
oSavedFile = new RandomAccessFile(sName,"rw"); * .e^s3q$
this.nPos = nPos; {E9Y)Z9
oSavedFile.seek(nPos); Uz0mSfBp
} ]?kf;A@
rg`"m
|peZ`O^~
public synchronized int write(byte[] b,int nStart,int nLen) =$m|M m[a
{ MG~^>
int n = -1; xzy9~))o
try{ eq"~by[Uq
oSavedFile.write(b,nStart,nLen); QKVZ![Y!s
n = nLen; =$HzEzrw
} !u^(<.xJ
catch(IOException e) p~r +2(J
{ DzYno-]A]
e.printStackTrace (); 4'{j'kuv
} Jzr(A^vwo
;a68>5Lm*
y"7?]#$9/
return n; `+<5QtD
} q* m%Fv
>iq^Ts
;1BbRnCr
} a/?gp>M9
#Zfg
Q.!8q3`
/* bJ9>,,D
**SiteInfoBean.java wZ*m
*/ TIS}'c'C
package NetFox; NxNz(R $~
Y2Tg>_:t
ecr pv+
public class SiteInfoBean { 4).q+{#k
|vzGFfRI
[*,`a]z-Q
private String sSiteURL; //Site's URL lGs fs(
private String sFilePath; //Saved File's Path 5HmX-+XpK
private String sFileName; //Saved File's Name wWwY.}j
private int nSplitter; //Count of Splited Downloading File +f|u5c
oZ!rK/qoA
YT#"HYO
public SiteInfoBean() ^f>+5G
{//nSplitter的缺省值为5 Nk]r2^.z[
//default value of nSplitter is 5 KO:o GUR
this("","","",5); X1$0'usS
} DUa`8cE}
-p9|l%W
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public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 5y@JMQSO
{ ~g)gXPjke
sSiteURL= sURL; Z5\u9E"]
sFilePath = sPath; l9#vr
sFileName = sName; jiz"`,-},O
this.nSplitter = nSpiltter; Q;SMwCB0M
KUZ'$oKg
N3i}>Q)B
} 4R@3jGXb8q
{B uh5U,
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public String getSSiteURL() b=.Ikt+y
{ 9aYCU/3
return sSiteURL; <SOC
} E[^66(KR
,H\EPmNHK
wF[^?K '
public void setSSiteURL(String value) wSnY;Z9W_
{ &.;tdT7
sSiteURL = value; &p`RKD
} 9psD"=/"
yiiYq(\{
"\U$aaF
public String getSFilePath() -#|J
{ *h$Z:p-g
return sFilePath; T[;O K
} bwS1YGb
>y &9!G
6m|j "m
public void setSFilePath(String value) :"|}oKT%mP
{ ![P1Qvp
sFilePath = value; O-@*xwD
} /MO|q
{YT!vD9.
EQET:a:g
public String getSFileName() ]=m '| 0}
{ kTL{?-
return sFileName; 5VDqx@(
} pZ}4'GnZI
2xN1=ug
51u8.%{4
public void setSFileName(String value) 4N|^Joi
{ !'Q/9%g
sFileName = value; 3i/$YX5@
} PF+v[h;,
y2bL!Y<s9
/pt%*;H
public int getNSplitter() wO;\,zU
{ C0eP/d
return nSplitter; n[H3b}
} yCy4t6`e
NpG5$?
wu"6Kyu
public void setNSplitter(int nCount) "T|%F D&[
{ i Tg?JoE2
nSplitter = nCount; 4mq+{c0
} rV>/:FG
} %]S~PKx
:Y`cgi0vkd
%8NAWDb{
/* Yq-Nk:H|
**Utility.java 2UU5\ jV6
*/ O:cta/M
package NetFox; mojD
;3wj(o0
{1,]8!HBJ
public class Utility { eY^;L_7}p
;O5p>o
UE33e(Q<
public Utility() q] eSDRW
{ Y>LgpO.
/*\pm!]._^
gmkD'CX*A
} (,<&H;,8
HQlhT
//线程睡眠 *NzHY;e
public static void sleep(int nSecond) ~=qJSb
{ HL-zuZa`Ju
try{ U9GmkXRix
Thread.sleep(nSecond); jkw:h0hX
} :a3 +f5
catch(Exception e) q y"VrR
{ 7A'd55I4
e.printStackTrace (); yDh(4w-~gk
} 6) {jHnk)
} 9fp@d
Qwl=/<p1
//日志 ns`|G;1vv
public static void log(String sMsg) o;bK 7D
{ JQ|qg\[
System.err.println(sMsg); uJ;7]
} rF C6"_
pGEYke NU
$t.i)wg +
public static void log(int sMsg) gx+bKGB`
{ y+D 3(Bsn
System.err.println(sMsg); j/"{tMqQp
} GQ<]Sd}[
} {B^V_TX2
za{z2#aJ
`@+}zE
/* Fl{:aq"3
**TestMethod.java Pp-\#WJ
*/ TS0x8,'$q
package NetFox; fh~"A`d
v^;-w~?3
!]]QbB
public class TestMethod { n#@/A
o!.\+[
|<nS<x
public TestMethod() ,nn5LQ|l.j
{ ///xx/weblogic60b2_win.exe 8\,|T2w,X
try{ JNhHQvi\
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); !: e(-
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); QoZ7l]^
SiteFileFetch fileFetch = new SiteFileFetch(bean); Tj &PB_v1
fileFetch.start(); ut6M$d4
} zh5'oE&[yC
catch(Exception e){e.printStackTrace ();} Z4YQ5O5
4o,%}bo&
97"dOi!Wh
} f:$LVpXS-
<~aQ_l
>r Nff!Ow
public static void main(String[] args) w k1O*_76
{ ]RYk Y7>`
new TestMethod(); ;zy[xg.7
} -rE_pV;
} rNzsc|a:
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