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)); cq'}2pob
} ^yEj]]6
for(int i=0;i<nEndPos.length-1;i++) Q0 uP8I}n
{ w>`h3;,2
nEndPos = nStartPos[i+1]; 7yq7a[Ra
} 1YF+(fk
nEndPos[nEndPos.length-1] = nFileLength; ``2QOu 1
} C8bGae(
} [H6X2yjj|
0?J|C6XM#4
3/A!_Uc(
//启动子线程 fD3jwPL
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; dy2_@/T7
for(int i=0;i<nStartPos.length;i++) rL!_&|
{ 'S%} ?#J
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 7/p J6>
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), AHp830\
nStartPos,nEndPos,i); .-O@UQx.I
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); '[M^f+H|
fileSplitterFetch.start(); ?$)x$nS`
} K$37}S5
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), %v`-uAy:
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Gh)sw72
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 8osS OOzM
nEndPos = " + nFileLength); ?d>P+).
// fileSplitterFetch[nPos.length-1].start(); xzMeKC`
/P?|4D}<
tn:/pPap
//等待子线程结束 ^.Ih,@N6
//int count = 0; @aqd'O
//是否结束while循环 |%2/I>o
boolean breakWhile = false; O$<%z[
OW63^wA`s
0]h8)EW
while(!bStop) xnRp/I
{ %X0NHta~@
write_nPos(); ]@ Sc}
Utility.sleep(500); <.AC=4@V
breakWhile = true; R[>;_}5">
@o3R`ZgC]\
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for(int i=0;i<nStartPos.length;i++) qUDz(bFk/
{ }`<>$2b
if(!fileSplitterFetch.bDownOver) C<wj?!v,F[
{ xT=kxyu
breakWhile = false; MWn L#!
break; SILvqm
} |peMr#
} ?2;n=&ZM
if(breakWhile) )-6s7
break; $)TF,-#x
+2au ;^N
QS=$#Gp
//count++; ?lET45'
//if(count>4) Br ^rK}|l
// siteStop(); "$V8y
} 1{Alj27
_iboTcUF
CI~;B
System.err.println("文件下载结束！"); 2YE]?!
} ]tdo&
catch(Exception e){e.printStackTrace ();} |jaY[_.@
} B[0,\>
?k:])^G5
\'LCC-
//获得文件长度 i!d7,>l+Q~
public long getFileSize() `Z7ITvF>
{ $vGEY7,
int nFileLength = -1; |YGiATD4DG
try{ oCdOC5
URL url = new URL(siteInfoBean.getSSiteURL()); MMA@J
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 2gD{Fgf@N
httpConnection.setRequestProperty("User-Agent","NetFox"); HsgTHe
:::f,aCAu
2b,TkG8K
int responseCode=httpConnection.getResponseCode(); X$&Sw3c
if(responseCode>=400) q.QYn.CBZz
{ v 4b`19}
processErrorCode(responseCode); a[cH@7W.#
return -2; //-2 represent access is error ZL@DD(S-/
} }o:sx/=u_
GWZXRUc
J<*Mk
String sHeader; S|4/C
iC+H;s5<
@VS5Mg8
for(int i=1;;i++) VEEeQy
{ H 7F~+Q-}
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); Z_~DTO2Qg
//Utility.log(in.readLine()); ?8}jJw2H
sHeader=httpConnection.getHeaderFieldKey(i); !jq6cND
if(sHeader!=null) ~2}ICU5
{ (3r,PS@Qq@
if(sHeader.equals("Content-Length")) jtr=8OiL
{ <sB45sNbU`
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); NS;8&
break; Zs|sPatV<
} #p`7gFl
} O~OWRJ@p
else :uDB3jN[
break; !`=?<Fl
} |?=1tS{iT
} ~At.V+
catch(IOException e){e.printStackTrace ();} S$On$]~\"
catch(Exception e){e.printStackTrace ();} n7uD(cL
vJUB;hD
rep"xV&|>o
Utility.log(nFileLength); S]g)^f'a65
Lpf=VyqC
=ApT#*D)o
return nFileLength; iUBni&B
} W^Y(FUy~
E/;YhFb[
>@uYleD(
//保存下载信息（文件指针位置） y<(.,Nb8
private void write_nPos() H4Ek,m|c
{ x=N;>
try{ &W!@3O{~.
output = new DataOutputStream(new FileOutputStream(tmpFile)); P@?CQvMx
output.writeInt(nStartPos.length); o]U==
for(int i=0;i<nStartPos.length;i++) T9?_ `h
{ &,7(Wab
// output.writeLong(nPos); $7YLU{0
output.writeLong(fileSplitterFetch.nStartPos); 6^Vf 5W{
output.writeLong(fileSplitterFetch.nEndPos); Su#1yw>
} GXVGU-br
output.close(); .R5z>:A
} 1j,Y
catch(IOException e){e.printStackTrace ();} S~Q";C[&
catch(Exception e){e.printStackTrace ();} PX)qA=4q
} h%S#+t(Bf
(p!AX<=z
#u@!O%MJ
//读取保存的下载信息（文件指针位置） Qpq0j^\
private void read_nPos() -NeF6
{ 8w'8n
try{ kq-RM#Dj:
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); qW^l2Jff
int nCount = input.readInt(); |\t_I~de
nStartPos = new long[nCount]; _Hk`e}}
nEndPos = new long[nCount]; H#E0S>Jw|
for(int i=0;i<nStartPos.length;i++) i,T{SV
{ qa0Zgn5q
nStartPos = input.readLong(); p4 PFoFo2
nEndPos = input.readLong(); 'C<=bUM
} 9qA_5x%"%u
input.close(); 3RUB2c4
} ?dYDfyFfB
catch(IOException e){e.printStackTrace ();} 5hMiCod
catch(Exception e){e.printStackTrace ();} o++Hdvai
} }I]q$3.
H<"j3qt
oP6G2@3P/
private void processErrorCode(int nErrorCode) v*LL7b0A
{ )FLpWE"e-
System.err.println("Error Code : " + nErrorCode); 1rC'sfz
} [tN/}_]
T9A5L"-6T
xj<SnrrC]u
//停止文件下载 =g:\R$lQ
public void siteStop() >smaR^m
{ yrX]w3kr%
bStop = true; :.,I4>b2
for(int i=0;i<nStartPos.length;i++) W+E2({
fileSplitterFetch.splitterStop(); mVLGQlvVK
pifgt
ITV}f#
} T$e_ao|
} Lnzhs;7L
//负责部分文件的抓取 `*a,8M%
**FileSplitterFetch.java *QX$Mo^E
*/ C0M{zGT>}
package NetFox; YAog;QL
uRIr,U^
VbjFQ@[l!
import java.io.*; 79v&6Io
import java.net.*; ;/.ZYTD
yT4|eHl
-]e@cevy
public class FileSplitterFetch extends Thread { {~SR>I3sv
5eYCnc9
]x|sTKv2
String sURL; //File URL >&R|t_ypw
long nStartPos; //File Snippet Start Position xM:dFS
long nEndPos; //File Snippet End Position |Bid(`t.
int nThreadID; //Thread's ID = U5)m
boolean bDownOver = false; //Downing is over 1gC=xMAT
boolean bStop = false; //Stop identical TsQMwV_h
FileAccessI fileAccessI = null; //File Access interface }\W3a_,v)
ll#PCgIm
"elh~K
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ,oCr6 ]
{ VioVtP0
this.sURL = sURL; U;(&!Ei
this.nStartPos = nStart; [;(|^0
this.nEndPos = nEnd; bke 1 F '
nThreadID = id; >g?,BK@
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ()rDM@
} Y4_i=}\*vf
l6&R g-
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public void run() z|9 ^T@)
{ v1} $FmHL"
while(nStartPos < nEndPos && !bStop) V{npK(
{ 43eGfp'
eRGip2^cq+
Uz0mSfBp
try{ i@2?5U>h
URL url = new URL(sURL); Z'EZPuZ!'
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 'j.{o
httpConnection.setRequestProperty("User-Agent","NetFox"); |peZ`O^~
String sProperty = "bytes="+nStartPos+"-"; (i`DUF'#y
httpConnection.setRequestProperty("RANGE",sProperty); th]9@7UE,
Utility.log(sProperty); +h =lAHn&
W?$ ImW
S\C
InputStream input = httpConnection.getInputStream(); }, ]W/
//logResponseHead(httpConnection); Nk7Q
vs.q<i-u
Sh"} c2
byte[] b = new byte[1024]; .G^.kg ,
int nRead; 43/|[
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) Dr;@)
{ !_]WUQvV?
nStartPos += fileAccessI.write(b,0,nRead); ^,?]]=mE
//if(nThreadID == 1) H}:apRb
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); Bdq/Ohw|!
} 6Up,B=sX0
% $ 5hC9
Tj.;\a|d
Utility.log("Thread " + nThreadID + " is over!"); ~oOOCB
bDownOver = true; ^UJO(
//nPos = fileAccessI.write (b,0,nRead); Q i?
} N&=,)d~M
catch(Exception e){e.printStackTrace ();} 8Uc#>Ae'_
} (ttO O45
} eX}uZR
[u~#F,_ow
#MI}KmH
//打印回应的头信息 h8nJ$jg
public void logResponseHead(HttpURLConnection con) |,qz7dpe
{ lGs fs(
for(int i=1;;i++) 7XdLZ4ub
{ Jln dypE
String header=con.getHeaderFieldKey(i); D7 .R NXo
if(header!=null) p7|~x@q+
//responseHeaders.put(header,httpConnection.getHeaderField(header)); VN*^pAzlF
Utility.log(header+" : "+con.getHeaderField(header)); G:f]z;Xdp
else W<kJ%42^j
break; (/c9v8Pr(7
} 2c}>}A4
} AWGeK-^
-p9|l%W
Io| 72W}rg
public void splitterStop() eja_+`cJ
{ M,:GMO:?a
bStop = true; kyz_r6
} '@rGX+"
Q;SMwCB0M
sJ!AI n<
} -cEjB%Neo
vxK}f*d
k.?b2]@$
/* 6wfCC,2
**FileAccess.java Ql!$e&A|l
*//文件访问(定位，写) u9QvcD^'z
package NetFox; zR">'bM:
import java.io.*; ;L++H5Kz6
6 C;??Y>b
C%0|o/Wi
public class FileAccessI implements Serializable{ }5FdX3YR
1]m]b4]
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 D8qZh1w%A|
RandomAccessFile oSavedFile; /c8F]fkZ=
long nPos; o"J}@nF
_6(QbY'JV`
-BgzAxa
public FileAccessI() throws IOException rhsSV3iM
{ s=#3f3
this("",0); :6./yj(
} sJ{NbN~`I
&%$r3ePwc
V)oUSHillH
public FileAccessI(String sName,long nPos) throws IOException /9QI^6&SX
{ Ir}r98lz
oSavedFile = new RandomAccessFile(sName,"rw"); t[XxLG*
this.nPos = nPos; D}r,t_]Eb
oSavedFile.seek(nPos); :"#EQq]ct
} swntz
:)SLi
m\)z& hv<r
public synchronized int write(byte[] b,int nStart,int nLen) 4jfkCU
{ oDXUa5x
int n = -1; 4#{i
try{ OEnJ".&V
oSavedFile.write(b,nStart,nLen); `B}(Ln
n = nLen; )4vZIU#
} FY|.eY_7 {
catch(IOException e) ,|,DXw
{ u[$ \ az7
e.printStackTrace (); . T6fPEb
} v}q3_m]
~pWbD~aeg
nw){}g
return n; 7{e0^V,\k
} EbZRU65J}O
l8/ tR
j'Z};3y
} /B73|KB+
![YLY&}s
{p&LwTnf
/* |r[yMI|VR
**SiteInfoBean.java -]\cUQ0
*/ ]PJb 9$f2
package NetFox; 1bs8fUPB3
v<c~ '?YzO
# Y/.%ch.
public class SiteInfoBean { AQ:cim`
mZDL=p
UE33e(Q<
private String sSiteURL; //Site's URL u;rK.3o
private String sFilePath; //Saved File's Path qfE>N?/
private String sFileName; //Saved File's Name m22M[L(q
private int nSplitter; //Count of Splited Downloading File O*^=
VDq4n;p1
!4cO]wh5
public SiteInfoBean() oace!si
{//nSplitter的缺省值为5 S(<r-bV<
//default value of nSplitter is 5 m2{3j[
this("","","",5); 9N5ptdP.d
} bkk1_X
x-O9|%aRJ
R?@F%J;tx
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) R r7r5
{ gRA}sF
sSiteURL= sURL; JbN@AX:%
sFilePath = sPath; _X5@%/Vz
sFileName = sName; dXR70/
this.nSplitter = nSpiltter; PF5;2
ns`|G;1vv
`|@#~
} wG6@.;3
s6Ox!)&
+mP&B<=H)
public String getSSiteURL() j.UQLi&`
{ f@U\2r
return sSiteURL; ,Y 1&[
} d3Dw[4
$%~-p[)<(P
_cra_(b
public void setSSiteURL(String value) ,'[&" Eg
{ e45gjjts
sSiteURL = value; ANB@cK_
} ds@X%L;_
Fl{:aq"3
Pp-\#WJ
public String getSFilePath() E#3KWp#M
{ )X*?M?~\
return sFilePath; R Fgy
} Q(@/,%EF
z.fh4p
#sl_ BC9
public void setSFilePath(String value) ShXk\"
{ 0ox 8_l
sFilePath = value; N[e QT
} `m2e *
"-aak )7w
gq9D#B
public String getSFileName() CNwYQe-i
{ QoZ7l]^
return sFileName; ~"\qX+
} h{zE;!+)D
[NQ\(VQ1c
dre@V(\;hQ
public void setSFileName(String value) =gI;%M\'
{ :eaqUW!Y
sFileName = value; Nda,G++5(
} Fua:& 77
+rEqE/QF
>dH5n$Gb
public int getNSplitter() /4 zO
{ L #'N
return nSplitter; f.f5f%lO~
} cG%ttfq\
RB]K?
p#vZYwe=L
public void setNSplitter(int nCount) /<Nb/#8
{ i!zh9,i>M
nSplitter = nCount; oZvQ/|:p!
} RG(m:N
} wg6![Uh
1FfdW>ay*
gcImk0NIY
/* k;V4%O
**Utility.java _Q<wb8+/
*/ XOl]s?6H$
package NetFox; :SxOQ(n
3#>;h
ejj|l
public class Utility { (]'Q!MjGa
Ph&AP*Fq
T-7'#uB.m
public Utility() iQ= %iou
{ L2ePWctq}
%gd=d0vm
O[RmQ8ll
} eqbxf#H!
ld1t1'I'
//线程睡眠 riI0k{
public static void sleep(int nSecond) b6D}GuW
{ dfB#+wh
try{ yhr\eiJ@6
Thread.sleep(nSecond); G'XlsyaWrb
} 1E Lzzn
catch(Exception e) R7us9qM4e
{ SdUtAC2
e.printStackTrace (); %8H*}@n
} 8VvoPlo
} kr7f<;rmJ
g~d}?B\<@
//日志 gf+Kr02~
public static void log(String sMsg) /U<-N'|
{ -tT{h4
System.err.println(sMsg); /:>f$k4~h
} dQ^>,(
64}Oa+*s
87EI<\mP
public static void log(int sMsg) !lE (!d3M
{ _1*EMq6
System.err.println(sMsg); !U#kUj:4I
} !mpRLBH
} h 88iZK
>H@ dgb
T4T_32`XR
/* ) 0$7{3
**TestMethod.java lfu1PCe5
*/ >82Q!HaH
package NetFox; 1oo'\
wpY%"x#-+=
uf`o\wqU
public class TestMethod { ksY^w+>(!
=(*Eh=Pw
1*?IDYB
public TestMethod() a#!Vi93
{ ///xx/weblogic60b2_win.exe [?W3XUJ,Y
try{ .x6*9z#q
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Pf)<6?T
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ,{itnKJC
SiteFileFetch fileFetch = new SiteFileFetch(bean); O<f_-n@G|
fileFetch.start(); X =S;8=N
} Mim 9C]h(
catch(Exception e){e.printStackTrace ();} WKBPqfC
-J!F((jt
_@sqCf%|
} wx(|$2{h
Pc? d@tm
30FYq?
public static void main(String[] args) l/LRr.x
{ *v:+AE
new TestMethod(); oX3Q9)
} &z{oVU+mA
} k4pvp5}%
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