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)); ~_fc=^o
} wa8jr5/k"
for(int i=0;i<nEndPos.length-1;i++) a9-Mc5^'n
{ NPK;
nEndPos = nStartPos[i+1]; ga;nM#/
} Uj7YTB
nEndPos[nEndPos.length-1] = nFileLength; k|/VNV( =0
} /oT~CB..
} ZAr6RRv ^
H~Uf2A)C
Sb[>R(0:
//启动子线程 SE+hB
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; {Dpsr` &
for(int i=0;i<nStartPos.length;i++) ',r` )9o
{ LP"g(D2'n
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), UjI./"]O
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), b*n3Fej
nStartPos,nEndPos,i); p< 7rF_?W0
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 4Hz3KKu
fileSplitterFetch.start(); 1kvX#h&V
} 93]63NY
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 0`x>p6.)G
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); AkQ(V
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", juR>4SH
nEndPos = " + nFileLength); uppa`addK
// fileSplitterFetch[nPos.length-1].start(); HPt3WBRzS;
z\m$>C|
U4"^NLAq
//等待子线程结束 v6 U!(x
//int count = 0; 9WG=3!-@
//是否结束while循环 ,/?J!W@m
boolean breakWhile = false; oJTEN}fL
Ak?9a_f
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while(!bStop) f SkC>mWv
{ h"1}j'2>@
write_nPos(); Fqeqn[,
Utility.sleep(500); }k VC]+
breakWhile = true; ,7B7X)m{3
P8YnKyI,.
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for(int i=0;i<nStartPos.length;i++) p6- //0qb
{ gX{j$]^6G8
if(!fileSplitterFetch.bDownOver) jWUrw
{ 9K&$8aD
breakWhile = false; ^UvL1+
break; 0XA\Ag\`G
} !f/K:CK|
} I0F[Z\U
if(breakWhile) u.2X"
break; k{f1q>gd
f!+d*9
x<l 5wh
//count++; WfO EI1
//if(count>4) dEDhdF#f
// siteStop(); sccLP_#Z
} gveGBi
|B(,53
aG7Lm2{c"
System.err.println("文件下载结束！"); bSIY|/d+
} N6[Z*5efR
catch(Exception e){e.printStackTrace ();} 'gN[LERT
} tV=Qt[|@
?*~ ~Ok
[\ku,yd%0
//获得文件长度 \;-Yz
public long getFileSize() @{IX do
{ <2(X?,N5BD
int nFileLength = -1; (hwzA *(c
try{ @>z.chM;
URL url = new URL(siteInfoBean.getSSiteURL()); F[coa5
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); eYv^cbO@:
httpConnection.setRequestProperty("User-Agent","NetFox"); Tcy9oYh!Pn
D!* SA
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int responseCode=httpConnection.getResponseCode(); QO$18MBcc
if(responseCode>=400) <@M5 C-hH
{ bzG vnaTt
processErrorCode(responseCode); J)g +I
return -2; //-2 represent access is error /[Nkk)8-
} "I=Lbh-`
-d?<t}a
`&=%p|
String sHeader; D Z~036
9vi+[3s/=;
_&HFKpHQ
for(int i=1;;i++) vmgd
{ s[4qC
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); F4=X(P_6
//Utility.log(in.readLine()); Ne9VRM P
sHeader=httpConnection.getHeaderFieldKey(i); l%V+]skS
if(sHeader!=null) ."Pn[$'.
{ Ks3YrKk;p
if(sHeader.equals("Content-Length")) -wUT@a
{ =n.&N
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); {U9{*e$=
break; *=md!^x`
} xz`0V}dPl
} Vb\^xdL>
else #pWy%U
break; r6D3u(kMb
} |xb;#ruR6
} "vYjL&4h
catch(IOException e){e.printStackTrace ();} N8T.Ye N
catch(Exception e){e.printStackTrace ();} yodhDSO5i
UChLWf|'
*r4FOA%P
Utility.log(nFileLength); >]B_+r0m^
2X`t&zg
7yG%E
return nFileLength; rXSw@pqZ&
} hB'rkjt
k'v+/6 Y
mb'{@
//保存下载信息（文件指针位置） PYCG#U
private void write_nPos() <}^p5|
{ )1R[~]y
try{ MHE/#G
output = new DataOutputStream(new FileOutputStream(tmpFile)); <&+0[9x
output.writeInt(nStartPos.length); (;Bh7Ft
for(int i=0;i<nStartPos.length;i++) 4{,!'NA
{ 0 Swu]OE
// output.writeLong(nPos); T2?.o.&u
output.writeLong(fileSplitterFetch.nStartPos); G~zfPBN0D
output.writeLong(fileSplitterFetch.nEndPos); _+}o/449
} 2(Xu?W 7d
output.close(); 4tkb7D q
} lE+Duap:
catch(IOException e){e.printStackTrace ();} 9r:|u:i7m
catch(Exception e){e.printStackTrace ();} \1u^?cBd
} 7#HSe#0J
uv$utu>< *
%f\j)qw
//读取保存的下载信息（文件指针位置） $5#DU__F/
private void read_nPos() OZKZv,
{ C,O9?t
try{ 1Uah IePf
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); F.Bij8\
int nCount = input.readInt(); }L`Z<h*H
nStartPos = new long[nCount]; &G-dxET]
nEndPos = new long[nCount]; $;";i:H`
for(int i=0;i<nStartPos.length;i++) ^c}kVQ\g3
{ >YdLB@
nStartPos = input.readLong(); [pt U}
nEndPos = input.readLong(); 2L.6!THG
} y`z?lmV)xM
input.close(); X~*/~f
} iDCQqj`
catch(IOException e){e.printStackTrace ();} zGL.+@
catch(Exception e){e.printStackTrace ();} m8l!+8
} ZKS]BbMZa
WK#c* rsij
),,0T/69+9
private void processErrorCode(int nErrorCode) dF&@q,
{ DEPsud;
System.err.println("Error Code : " + nErrorCode); (nkiuCO
} &[|Z2}
16ip:/5
>qMzQw2
//停止文件下载 l:a#B
public void siteStop() !h^_2IX
{ g/!tp;e
bStop = true; *I9O63
for(int i=0;i<nStartPos.length;i++) nWd;XR6|
fileSplitterFetch.splitterStop(); z@<jZM
f(EO|d^u
1#zD7b~
} i\>?b)a>
} ^= kr`5
//负责部分文件的抓取 '~{kR=+
**FileSplitterFetch.java 2/))Y\~
*/ 4?_^7(%p
package NetFox; R<r,&X?m
!%D;H~mQ
$m-@ICG#
import java.io.*; 6,l5Q
import java.net.*; +}g6X6m
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FZ FPzH
public class FileSplitterFetch extends Thread { Lu71Qdu09
*y~~~ 'J/
x45F-w{
String sURL; //File URL wF-H{C'
long nStartPos; //File Snippet Start Position H:q;IYE+a
long nEndPos; //File Snippet End Position U]M5&R=?
int nThreadID; //Thread's ID a3[,3
boolean bDownOver = false; //Downing is over Eh *u6K)Z
boolean bStop = false; //Stop identical R,l*@3Q
FileAccessI fileAccessI = null; //File Access interface #=ko4?Wr(
}'p*C$
'kJyE9*xU.
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException K7,Sr1O `
{ y+',jM
this.sURL = sURL; ( _MY;S
this.nStartPos = nStart; ]0")iY_
this.nEndPos = nEnd; EO/TuKt
nThreadID = id; ,H/BW`rL]#
fileAccessI = new FileAccessI(sName,nStartPos);//定位 N.V5>2
} $%1oZ{&M
] `;Fc8$
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public void run() *b`1+~p_2
{ TOx@Y$_9Q8
while(nStartPos < nEndPos && !bStop) 4=njM`8Y'
{ 1#XZVp;M
Tog'3k9Uw
ka$la;e3
try{ 1/=6s5vS}
URL url = new URL(sURL); e=ry_@7
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 0J.]`kR
httpConnection.setRequestProperty("User-Agent","NetFox"); |-]'~@~
String sProperty = "bytes="+nStartPos+"-"; !3ji]q;uF
httpConnection.setRequestProperty("RANGE",sProperty); c`UizZ
Utility.log(sProperty); =_$Hn>vO
4@jX{{^6%
&8JK^zQq
InputStream input = httpConnection.getInputStream(); o}L\b,])
//logResponseHead(httpConnection); Vo(bro4ZQi
5QG?*Z~?7
i&L!?6 5-f
byte[] b = new byte[1024]; =pb ru=/
int nRead; Nfd'|#
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) nYTPcT4x|
{ 3g3Znb
nStartPos += fileAccessI.write(b,0,nRead); }n k[WW
//if(nThreadID == 1) !dwa. lZ&X
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); WFfn:WSWU
} :!wt/Y
76cT}l&.h8
r_Pi)MPc
Utility.log("Thread " + nThreadID + " is over!"); C!|Yz=e
bDownOver = true; fjqd16{Q
//nPos = fileAccessI.write (b,0,nRead); O]?PC^GGY
} !)EYM&:Y
catch(Exception e){e.printStackTrace ();} 2zkOs:
} \| 'Yuh
} D0X!j,Kc
+o K*5 Y
)D7/[zb^
//打印回应的头信息 @lCyH(c%
public void logResponseHead(HttpURLConnection con) R-Gg= l5
{ :;w#l"e7<
for(int i=1;;i++) =DXN`]uN
{ T@ zV
String header=con.getHeaderFieldKey(i); 8M7Bw[Q1
if(header!=null) $AdBX}{
//responseHeaders.put(header,httpConnection.getHeaderField(header)); vSwRj<|CF
Utility.log(header+" : "+con.getHeaderField(header)); (~?p`g+I.P
else ,b t j6hg
break; rb]?"lizi
} |}o3EX
} 2I_~]X53[
3yLJWHO%W
U<6+2y P
public void splitterStop() kK.[v'[>&
{ ZDmY${J
bStop = true; ^]?juL
} R|]n;*y
{vp*m:K
}qBmt>#
} 5I/lFoy7
fN6n2*wr(
"Ve9\$_s
/* `r&]Ydu:
**FileAccess.java vywpX^KPv
*//文件访问(定位，写) 9<5S!?JL
package NetFox; >LW}N!IBy
import java.io.*; ~P'i /*:
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@el
public class FileAccessI implements Serializable{ c-ql
D"&Sd@a{
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 6>z,7 [
RandomAccessFile oSavedFile; A5Lzd
long nPos; \%&eDE0
dEZlJo@J
XmN8S_M>v
public FileAccessI() throws IOException ;KT5qiqYH
{ zxeT{AFPr?
this("",0); -0P9|;h5
} ^p3W}D
]#vi/6\J
sEi9<$~R@0
public FileAccessI(String sName,long nPos) throws IOException b8glZb*$
{ gKtgW&PYm
oSavedFile = new RandomAccessFile(sName,"rw"); eU8p;ajW!L
this.nPos = nPos; WJN)<+d
oSavedFile.seek(nPos); #Sg"/Cc
} 6!wk5#
(QQkXlJ
6i%Xf i
public synchronized int write(byte[] b,int nStart,int nLen) wYQEm
{ R$;TX^r'o&
int n = -1; S:1g(f*85
try{ ,(NN)Oj
oSavedFile.write(b,nStart,nLen); ~JO.h$1C
n = nLen; <jBRUa[j_
} @4n>I+6*&
catch(IOException e) :TkMS8
{ e9>~mtx
e.printStackTrace (); <6X*k{
} e0hY
tTWEhHQ`
*q+X?3
return n; "<LWz&e^^
} X!m lC51
],Yy)<e.
/@I`V?Q!a
} P~%+KxwZQ
&0xM 2J
/i#";~sO
/* 2+ywl}9
**SiteInfoBean.java ?hViOh$.
*/ lSc=c-iOv
package NetFox; L@Q+HN
8[D"
qw{`?1[+
public class SiteInfoBean { }_5R9w]"
Udq!YXE0
\>X!n2rLZe
private String sSiteURL; //Site's URL QNH3\<IS
private String sFilePath; //Saved File's Path z"Mk(d@-E
private String sFileName; //Saved File's Name mhB2l/
private int nSplitter; //Count of Splited Downloading File ij;P5OA
buT6)~lw
_n_()at)
public SiteInfoBean() ;a| ~YM2I
{//nSplitter的缺省值为5 6@eF|GoP
//default value of nSplitter is 5 :>U+HQll
this("","","",5); E;[Uhh|78!
} dT[JVl+3=
h~ZLULW)B
wE}Wh5
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) u1=K#5^
{ 7*"Jx}eM
sSiteURL= sURL; 5JHEBw5W%
sFilePath = sPath; U_l9CZ
sFileName = sName; YoBe!-E
this.nSplitter = nSpiltter; v*%52_
5DVYHN9c|
b` va\'&3
} ~]q>}/&YLo
2_y]MXG+%
"c|Rpzs[
public String getSSiteURL() 5~j#Z (}u
{ >##Z}auY
return sSiteURL; D:/q<<|
} w)`XM
@\o"zU
&BRa5`
public void setSSiteURL(String value) |Wjpnz
{ Pc2!OQC'""
sSiteURL = value; UtP|<]{
} -Jw4z#/-
FSn3p}FVa
6)7cw8^
public String getSFilePath() ex6R=97uA
{ hzRKv6
return sFilePath; g5lb3`a3
} gKQV99
W"GW[~ h
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public void setSFilePath(String value) I7~) q`
{ ~f[ Y;
sFilePath = value; *3rs+0
} ft$RF
|`t 6lVO,Z
H!&_Tv[
public String getSFileName() t%%()!|)j
{ QXN_ ?E,g/
return sFileName; *BdH &U
} y.c6r> }
n:P:im?,y*
_+'!l'`
public void setSFileName(String value) -Ep#q&\
{ L!lmy&1
sFileName = value; P_w4 DU
} ".N+nM~
>6HGh#0(p
;RRw-|/Wm
public int getNSplitter() zQG{j\
{ >36,lNt
return nSplitter; X;N?L%Pp
} ^'0N%`bY!
r PK.Q)g
!*Eu(abD
public void setNSplitter(int nCount) \yC/OLXq
{ sQac%.H;`U
nSplitter = nCount; f!`?_
} 6{Q-]LOc[.
} [&PF ;)i
kM{8zpn
bXOKC
/* )38%E;T{X
**Utility.java (u} /(Ux
*/ ]i@73h YT
package NetFox; }`g-eF>p
4P k%+l
XFvl
public class Utility { .JXEw%I@
hHU=lnO
CV.|~K0O
public Utility() &h5Y_no GX
{ fy4zBI@
]i$y;]f
:sJ7Wok6~
} VMRfDaO9
!>n!Q*\(Ov
//线程睡眠 b4i=%]v8
public static void sleep(int nSecond) $3G^}A"
{ O573AA
try{ zMFTkDY
Thread.sleep(nSecond); >kK@tJn
} ZBK0`7#&EH
catch(Exception e) H3<tsK=:
{ 1+uZF
e.printStackTrace (); CTRUr"
} r)pt(*KHo
} C$TU TS
ou<3}g
//日志 )>:~XA|?
public static void log(String sMsg) A}(]J!rc
{ pE)NSZ
System.err.println(sMsg); Ee2P]4_d
} jJ$B^Y"4
!SW0iq[7j
<@KIDZYC
public static void log(int sMsg) kt2_WW[
{ 8%#8PLB2
System.err.println(sMsg); X]p3?"7
} OW4j!W
} qqf`z,u
t.28IHJ
U 5J _Y
/* LJ/He[r|[
**TestMethod.java CF{b Yf^%
*/ &/]en|f"
package NetFox; $qQYxx@
]O"f%
r6Yd"~ n
public class TestMethod { ,r w4Lo
/B@{w-N
a31e.36g
public TestMethod() k i<X^^
{ ///xx/weblogic60b2_win.exe S@HC$
try{ uI7n{4W*x
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); !HDb{f
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); g2|Myz)
SiteFileFetch fileFetch = new SiteFileFetch(bean); <J&S[`U!
fileFetch.start(); f47]gtB-
} EVX3uC}{
catch(Exception e){e.printStackTrace ();} pD%(Y^h?
O D}RnKL
~~OFymQ%?q
} CW &z?Bra
#y:D{%Wp
OB(oOPH
public static void main(String[] args) x950,`zy
{ o:AfEoH"~
new TestMethod(); %;k Hnl
} eUA]OF@
} >o?v[:u*
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