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)); f ~Fus
} ^)fB "!s
for(int i=0;i<nEndPos.length-1;i++) qA"?5j32
{ rBny*!n
nEndPos = nStartPos[i+1]; BR0bf5T/
} 9s7B1Pf
nEndPos[nEndPos.length-1] = nFileLength; =vK(-h
} T.(SBP
} xE)pj|
o<g (%ncr
Ko%rB+d
//启动子线程 qlgh$9
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; Uc6U!X
for(int i=0;i<nStartPos.length;i++) ~Snw':
{ qy-BZ%3
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 2XXEg>CU
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), *uv\V@0
nStartPos,nEndPos,i); :ZzG5[o3
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ntF(K/~Y
fileSplitterFetch.start(); EAq >v t83
} 1gt[_P2u
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), d@w I: 7
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Yb6\+}th
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", qkBnEPWZy
nEndPos = " + nFileLength); qb9%Y/xy
// fileSplitterFetch[nPos.length-1].start(); WYh7Y
5o72X k
>)5vsqGZaK
//等待子线程结束 sV*Q8b*
//int count = 0; 3;M!]9ms
//是否结束while循环 3$kZu
boolean breakWhile = false; &G"]v]V
XSxya.1
1/fvk
while(!bStop) -~-2 g
{ '{+hti,Lh
write_nPos(); K3Xy%pqR#
Utility.sleep(500); *Z0}0< D@Z
breakWhile = true; @+2Zt%
V2y[IeSQ
_ Po9pZ
for(int i=0;i<nStartPos.length;i++) Ec[:6}
{ 6@$[x* V
if(!fileSplitterFetch.bDownOver) K{iayg!k
{ *1%g=vb
breakWhile = false; {Ise (>V
break; \agC Q&
} TxiJ?sDh*
} DBv5Og
if(breakWhile) Th8Q~*v
break; pE`(kD
\UC4ai2MK
1rKR=To
//count++; .DX#:?@4@Y
//if(count>4) +amvQ];?Q8
// siteStop(); awawq9)Y
} O@$hG8:
^Uf`w7"iY
O7K))w
System.err.println("文件下载结束！"); vd;wQ
} _AO0:&
catch(Exception e){e.printStackTrace ();} lu{}j4
} :#LB}=HQ
dHu]wog
Ltj}>.+
//获得文件长度 l-Xxv
public long getFileSize() RS:0xN\JN
{ MVj@0W33m
int nFileLength = -1; Z/I!\
try{ eGE%c1H9a
URL url = new URL(siteInfoBean.getSSiteURL()); hT_snb;ow
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); BNByaC
httpConnection.setRequestProperty("User-Agent","NetFox"); f>'7~69
=?2y <B
c]LH.
int responseCode=httpConnection.getResponseCode(); ZD<,h` lZ
if(responseCode>=400) *dQRs6
{ J\%:jg( m
processErrorCode(responseCode); Zb1v
return -2; //-2 represent access is error f"tO*/|`
} PU>;4l
FFkG,XH
jmb\eOq+~V
String sHeader; 63f/-64?7
#[si.rv->
H z6H,h
for(int i=1;;i++) q[#\qT&QU
{ u1"e+4f
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 9@j~1G%^
//Utility.log(in.readLine()); <V,?!}V
sHeader=httpConnection.getHeaderFieldKey(i); l&rDa=m.J
if(sHeader!=null) [0}471
{ 5>=tNbk"s
if(sHeader.equals("Content-Length")) eS"gHldz
{ Brl6r8LGi
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); EvYw$j
break; <Kh\i'8
} ZJ4"QsF
} JC#@sJ4az)
else YOY+z\Q
break; U%4g:s
} -Z Z$ 1E
} 06`__$@h
catch(IOException e){e.printStackTrace ();} _(jE](,
catch(Exception e){e.printStackTrace ();} 3UaP7p+d
j\vK`.z
daorKW4
Utility.log(nFileLength); =.%ZF]Oe+#
x B?:G
-r2cK{Hhp&
return nFileLength; cU>&E*wD
} 7mjj%
QA3l:D}u
KZE.}8^%D
//保存下载信息（文件指针位置） 2eK\$_b_
private void write_nPos() y((_V%F}
{ WY,t> 1c
try{ @v'D9 ?
output = new DataOutputStream(new FileOutputStream(tmpFile)); I>xB.$A
output.writeInt(nStartPos.length); 4"2/"D0
for(int i=0;i<nStartPos.length;i++) c,qCZ-.Sg
{ )k1,oUx
// output.writeLong(nPos); \XN5))
output.writeLong(fileSplitterFetch.nStartPos); @b/2'
output.writeLong(fileSplitterFetch.nEndPos); `SW " RLS3
} 2mO#vTX4
output.close(); mx[^LaR>v
} o`U\Nhq
catch(IOException e){e.printStackTrace ();} VB#31T#q?
catch(Exception e){e.printStackTrace ();} g5Vr2
} 2%8Y-o?
3oKGeB;Ja
[0LqZ<\5
//读取保存的下载信息（文件指针位置） %(Ys-GeGr
private void read_nPos() ""+*Gn7^8
{ pd1m/:
try{ Psa8OJan
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); C{Ug ?hVP
int nCount = input.readInt(); ]Yu+M3Fq
nStartPos = new long[nCount]; CJOl|"UyJ
nEndPos = new long[nCount]; ]aRD6F:L
for(int i=0;i<nStartPos.length;i++) qWpCe*C
{ -IS9uaT5
nStartPos = input.readLong(); O}-7 V5
nEndPos = input.readLong(); {|h"/
} Qzhnob#C9
input.close(); -X[[ OR9+
} \?^wu
catch(IOException e){e.printStackTrace ();} PQ]9xzOg[
catch(Exception e){e.printStackTrace ();} G7;}309s
} EM*OrUe
LPn}QzH
#<PdZl R
private void processErrorCode(int nErrorCode) 5Nb_K`Vp*
{ ehusI-q
System.err.println("Error Code : " + nErrorCode); 5)7mjyo%
} /vDF<HVzm
S7/v,E
\,!q[nC
//停止文件下载 fti|3c
public void siteStop() 1^#Q/J,
{ t"p#iia
bStop = true; ]M(f^
for(int i=0;i<nStartPos.length;i++) 9u@h`
fileSplitterFetch.splitterStop(); FBAC9}V"
} XU:DE
kV3j}C"
} uW~,H}E
} x2sOEkcQ
//负责部分文件的抓取 bJF/daC5
**FileSplitterFetch.java .4W>9 8
*/ P i!r}m
package NetFox; )hW {>Y3x
}.) 43(>]
4_I{Q^f
import java.io.*; d`<^+p)oy
import java.net.*; =k=2~ j
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pf@}4PN}
public class FileSplitterFetch extends Thread { *.c9$`s
(I ds<n"
K=?F3tX^
String sURL; //File URL ]C6[`WF
long nStartPos; //File Snippet Start Position idS RWa
long nEndPos; //File Snippet End Position zZc@;S#
int nThreadID; //Thread's ID Qz(T[H5%W
boolean bDownOver = false; //Downing is over qetP93N_*
boolean bStop = false; //Stop identical fsc~$^.~\
FileAccessI fileAccessI = null; //File Access interface DIp:S&q2
"ue$DyN
#Rx"L&3Ue
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException wLN2`ucC
{ d"6]?
this.sURL = sURL; tW:/R@@
this.nStartPos = nStart; N8YBu/
this.nEndPos = nEnd; j~S!!Z]
nThreadID = id; KBRg95E~]l
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ;3}EBcw)
} H\+c'$
5%+bWI{w
pb6^sA%l
public void run() `vxrC&,As
{ kqvJ&7
while(nStartPos < nEndPos && !bStop) P"uHtHK
{ 8H#c4%by)
Owpg]p yVD
,PMb9O\B
try{ B/D\gjb
URL url = new URL(sURL); ,V]A63J
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); RvSq KW8
httpConnection.setRequestProperty("User-Agent","NetFox"); sMS9!{A
String sProperty = "bytes="+nStartPos+"-"; Wj j2J8B
httpConnection.setRequestProperty("RANGE",sProperty); sp Q4m
Utility.log(sProperty); z2Y_L8u2
W+f&%En
@ZkAul0@
InputStream input = httpConnection.getInputStream(); B+e_Y\Bu
//logResponseHead(httpConnection); tkN3BQ
NC.P2^%
QYTTP6 Gz+
byte[] b = new byte[1024]; yEUNkZ5^
int nRead; PWk?8dL-
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ]6BmCh
{ *Qg5Z
nStartPos += fileAccessI.write(b,0,nRead); ZE8/ m")
//if(nThreadID == 1) &[ u6oAR
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); X`3vSCn
} B>|U-[A
8gbm"!
B3>Uba*-)}
Utility.log("Thread " + nThreadID + " is over!"); \l]pe|0EW
bDownOver = true; 'y6!%k*
//nPos = fileAccessI.write (b,0,nRead); {y&\?'L'
} a()6bRc~T
catch(Exception e){e.printStackTrace ();} (' Ko#3b
} Cl9SPz
} ?z@v3(b[
;o)=XEh8P
]]uzl0LH
//打印回应的头信息 bwSRJFqb
public void logResponseHead(HttpURLConnection con) 5hJYy`h~
{ @4_rxu&
for(int i=1;;i++) =(.mf
{ Rnj Jg?I=
String header=con.getHeaderFieldKey(i); 5]H))}9>d
if(header!=null) l$-=Pqb
//responseHeaders.put(header,httpConnection.getHeaderField(header)); xxoHH#a
Utility.log(header+" : "+con.getHeaderField(header)); ;5D@kS^
else i.&Kpw9;m
break; XSp x''l
} H-_^TB
} D/S>w(=
M9Nk=s! 3
qIDWl{b<
public void splitterStop() {b|3]_-/
{ yE.495
bStop = true; )l#%.Z9
} :Hzz{'
(:?5 i`
GJC!0{8;
} *(d6Z#
8tLT'2+H#
{=bg5I0|a
/* ]&C:>
**FileAccess.java YN%=Oq
*//文件访问(定位，写) j<ABO")v
package NetFox; %tzN@
import java.io.*; s;B j7]
?qg^WDs$
s-,=e
public class FileAccessI implements Serializable{ hv$uH7Fz
5u;Rr 1D
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 !,? <zg
RandomAccessFile oSavedFile; r~$}G-g
long nPos; 7P/?wv9+n*
[$( sUc(%
4_Qa=T8
public FileAccessI() throws IOException vzY'+9q1.
{ ]aC':55(
this("",0); %[]"QbF?
} MkG`w,
{{V;:+62
T-a&e9B
public FileAccessI(String sName,long nPos) throws IOException 'Q:i&dTg
{ cWN d<=Jp
oSavedFile = new RandomAccessFile(sName,"rw"); MzEm*`<
this.nPos = nPos; HGO#e
oSavedFile.seek(nPos); !,cQ'*<W8-
} :3KO6/+
r{t.c?/
IL~]m?'V(
public synchronized int write(byte[] b,int nStart,int nLen) P0%N Q1bn
{ n-b>m7O(
int n = -1; k{gl^
try{ 42rj6m\
oSavedFile.write(b,nStart,nLen); fL ~1
n = nLen; ?,ZELpg n
} = EQN-{#
catch(IOException e) w^06z,
{ H$z>OS_6U
e.printStackTrace (); BFBR/d[&
} m b%C}8D
W(;x\Nc7
zKIGWH=qqm
return n; !oZQ2z~
} %04:z77
i{o#3
[Ja)<!]<
} _1I K$gb[
@%6)^]m}r
cC^W2\
/* 9@:BK;Fi
**SiteInfoBean.java QCeMKjCmY
*/ H@K#|A=a
package NetFox; 'e}uvbK
=yl4zQmg$
v1LKU
public class SiteInfoBean { `wNm%*g
).pO2lLF4
/8f>':zUb
private String sSiteURL; //Site's URL an3~'g?
private String sFilePath; //Saved File's Path AXz-4,=xX
private String sFileName; //Saved File's Name *:a'GC%/
private int nSplitter; //Count of Splited Downloading File %lN2n,AK
!\QeBd+
wk" l[cH>
public SiteInfoBean() 3(1]FKZtt
{//nSplitter的缺省值为5 b6 $,Xh
//default value of nSplitter is 5 T!MZ+Ph`F
this("","","",5); d; 9*l!CF
} iJFr4o/R
hT?6sWa
a "R7JjH
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) %1Yz'AiW[
{ oFWt(r
sSiteURL= sURL; +`ai1-vw
sFilePath = sPath; 59V#FWe-
sFileName = sName; OkLz^R?d
this.nSplitter = nSpiltter; 3)}(M
W%TQYR
+wipfL~&S
} 538fK9[
:*^:T_U
Vzpt(_><
public String getSSiteURL() 59.$ULQVMY
{ X4a^mw\"
return sSiteURL; }i(qt&U;
} 5?Bc Y;
2z4<N2!M
'!p=aF9L
public void setSSiteURL(String value) grr'd+_e
{ aSel* L
sSiteURL = value; aYqm0HCT
} :pRF*^eU
+#4]o }6G
tv0Ha A
public String getSFilePath() T=WNBqKo]
{ UH[<&v
return sFilePath; uKv&7p@|_)
} aR _NyA
qP7G[%=v
WJfES2N
public void setSFilePath(String value) 2UiR~P]%
{ ~/2g)IS
sFilePath = value; {;*}WPYb
} ]bm=LA
"f4<B-9<$
a5|@R<iF
public String getSFileName() f-4.WW2FN
{ P|N2R5(>T
return sFileName; Jy]Id*u9
} 6JhMkB^h
@D)Z{=>{=5
L7]]ZAH!1
public void setSFileName(String value) uMvb-8
{ g5i#YW
sFileName = value; []zua14F6
} [>f]@>
6gnbkpYi
&f-hG3/M
public int getNSplitter() ND5$bq Nu?
{ \@K~L4>
return nSplitter; gw^'{b
} T?n-x?e
WWNu:,
kx:jI^
public void setNSplitter(int nCount) ?R|th Z
{ VevNG*
nSplitter = nCount; =s;M]:
} 4J5pXlzV
} FbAW_Am(
<C'Z H'p
v`x|]-/M&
/* :'}@Al9=>
**Utility.java 'Dath>Y=
*/ }$&xTW_
package NetFox; 6V1:qp/6
aE)by-'
z\TLsx
public class Utility { ^z~~VBv
+6l]]*H
L[y Pjw:0
public Utility() )#C mQXgG
{ RF?DtNuq
L&kr{7q
CE ~@}`
} _okWQvdH
(?>cn_m
//线程睡眠 9pLg+6O
public static void sleep(int nSecond) ~jN'J+_$
{ eh(<m8I
try{ sZg6@s=
Thread.sleep(nSecond); ;JT(3yK4>p
} 7&U&E|
catch(Exception e) 6S1m<aH6
{ _Zc4=c,K
e.printStackTrace (); O,s.D,S
} P|xG\3@Z
} .TpsJXF
M:n6BC>t"
//日志 ~Y7dH Dn
public static void log(String sMsg) S_b/DO
{ Xj@+{uvQB
System.err.println(sMsg); `)Ky0&?
} 0 )}$^TV
X(*!2uS
L(G92,.
public static void log(int sMsg) TTZe$>f
{ ~aTKG|74
System.err.println(sMsg); <jA105U"m>
} tU@zhGb
} "35A/V
]*N1t>fb
Udgqkl
/* ,SUT~oETP
**TestMethod.java )d`mvZBn1
*/ Da.G4,vLh
package NetFox; -SCM:j%h
~F!,PM/
H:QhrL+7_
public class TestMethod { V '.a)6
*if`/N-q(m
CvDxq:x
public TestMethod() Bp?
{ ///xx/weblogic60b2_win.exe &7>zURv
try{ 56}X/u
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); [f/I2
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); F<|t\KOW
SiteFileFetch fileFetch = new SiteFileFetch(bean); B^v8,;jZT
fileFetch.start(); 8sOQ9
} O;uG?.\
catch(Exception e){e.printStackTrace ();} `]i []|
%*}Y6tl'|
"ju'UOcS/
} iE].&>w
0~Gle:
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public static void main(String[] args) Fc6iQ
{ 'b&yrBFD
new TestMethod(); g>JLDQdc
} ;i<jhNA
} ";SiL{Z
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