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)); ]\P
} ?"AcK"v
for(int i=0;i<nEndPos.length-1;i++) ,%dn)gt7
{ ;BoeE3* 6
nEndPos = nStartPos[i+1]; e,I-u'mLQs
} M:?eK [h
nEndPos[nEndPos.length-1] = nFileLength; M 0->
} |6\ ?"#
} _}Jz_RS2`
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Fw:s3ON9}
//启动子线程 Y_PCL9G{p
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 9>le-}~
for(int i=0;i<nStartPos.length;i++) )+w0NhJw
{ A'|W0|R9
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), :KX/GN!n
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), I?-9%4 8iM
nStartPos,nEndPos,i); Ltcr]T(Ic
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); C bG"8F|4
fileSplitterFetch.start(); [.z1
} #f/-iu=L
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), SVXey?A;CJ
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); x#dJH9NR[
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", @R}L 4
nEndPos = " + nFileLength); $K<jmEC@<
// fileSplitterFetch[nPos.length-1].start(); $yaE!.Kc
@c$mc
e5fJN)+a
//等待子线程结束 T:cSv @G
//int count = 0; 9L:v$4{LU
//是否结束while循环 ;?inf`t
boolean breakWhile = false; |c8p{)
jopC\Z
0; V{yh
while(!bStop) BY,%+>bc)
{ 1[3"|
write_nPos(); !^q<)!9<EO
Utility.sleep(500); mMT7`r;l
breakWhile = true; -lSm:O@'
pSq\3Hp]Q
`-ENKr]
for(int i=0;i<nStartPos.length;i++) =]W{u`
{ 5bmtUIj
if(!fileSplitterFetch.bDownOver) )IZ$R*Y{
{ @ n;WVG
breakWhile = false; ~n"V0!:'4
break; a3Es7R+S
} 0]>p|m9K^<
} V^L;Nw5h
if(breakWhile) HdWghxz?)
break; LZ&CGV"Z-
#3u8BLy$Q
=K8`[iH
//count++; D zDt:.JZ
//if(count>4) y L&n)
// siteStop(); [zf9UUc~
} f.+e
l`$f@'k
ci3{k"
System.err.println("文件下载结束！"); 9M01}
} X[;4.imE
catch(Exception e){e.printStackTrace ();} 2b|vb}|t{
} ,b{G(sF
-]'Sy$,A
MiOSSl};
//获得文件长度 zi*D8!_C
public long getFileSize() e4CG=K3s
{ L4kYF~G:4
int nFileLength = -1; r="X\ [on
try{ 5+3Z?|b
URL url = new URL(siteInfoBean.getSSiteURL()); 9@D,ZSi
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); RFA5vCG
httpConnection.setRequestProperty("User-Agent","NetFox"); k_}ICKzw1
8-8= \
#On1Q:d
int responseCode=httpConnection.getResponseCode(); J_P2%b=C
if(responseCode>=400) 4TR:bQZs
{ XTW/3pB
processErrorCode(responseCode); y'pG'"U]_
return -2; //-2 represent access is error bJ. ((1$
} R4V>_\D/
+oQ@E<)H
Za}91z"
String sHeader; TS3 00F
E?08=$^5%
l^0 <a<P
for(int i=1;;i++) :syR4A WM
{ $g|g}>Sc
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); QT%&vq
//Utility.log(in.readLine()); IHagRldG
sHeader=httpConnection.getHeaderFieldKey(i); W=)}=^N0
if(sHeader!=null) )SDGj;j+
{ tO~H/0
if(sHeader.equals("Content-Length")) [BV{=;iD
{ SxT:k,ji
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); g>f(5
break; ;utjW1y
} aUA+%
} dd4yS}yBlR
else G0*$&G0nb
break; ,sLV6DM
} VJr?` eY4
} SH}O?d\Q:
catch(IOException e){e.printStackTrace ();} Uc9Uj
catch(Exception e){e.printStackTrace ();} f4w|
OB$A"XGAEV
tU)+q?Mw
Utility.log(nFileLength); NU 6P
'Z&A5\~
N+}yw4lb
return nFileLength; 3rR(>}:[V
} 2,_BO6 !d
BwBv'p+n
t<:XY
//保存下载信息（文件指针位置） VJ1`&
private void write_nPos() u8[X\f
{ 9Xm"kVqd/
try{ |`O7>(h
output = new DataOutputStream(new FileOutputStream(tmpFile)); F`?pZ
output.writeInt(nStartPos.length); V@Po}
for(int i=0;i<nStartPos.length;i++) N$=<6eQm
{ fYCAwS{
// output.writeLong(nPos); Z)?"pBv'
output.writeLong(fileSplitterFetch.nStartPos); AMO{?:8Y;
output.writeLong(fileSplitterFetch.nEndPos); pCg0xbc`
} zSq+#O1#
output.close(); j f^fj-
} 14^t{
catch(IOException e){e.printStackTrace ();} o^AK@\e:^Z
catch(Exception e){e.printStackTrace ();} ul% q6=f)
} TkQ05'Qc
OK2wxf
e|kYu[^
//读取保存的下载信息（文件指针位置） m*I5 \
private void read_nPos() a{u)~:/G
{ w93yhV?
try{ ].1R~7b
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ^|gN?:fA}
int nCount = input.readInt(); 4s$))x9p
nStartPos = new long[nCount]; da2BQ;
nEndPos = new long[nCount]; 52%.^/
for(int i=0;i<nStartPos.length;i++) wPG3Ap8L
{ I.( 9{
nStartPos = input.readLong(); "+HZ~:~f
nEndPos = input.readLong(); 4z$eT
} 7tt&/k?Q
input.close(); #D}NT*w/
} rP>5OLP
catch(IOException e){e.printStackTrace ();} ^Nc\D7( l
catch(Exception e){e.printStackTrace ();} xwz2N5
} &t6L8[#yd
_ :][{W#
`#l_`j=r$
private void processErrorCode(int nErrorCode) WRo#ZVt9$
{ ]*v%(IGK
System.err.println("Error Code : " + nErrorCode); l5@k8tnz
} q=6M3OnS>
~w!<J-z)
X#Hs{J~@p
//停止文件下载 ;>YJ}:r"\
public void siteStop() gWJLWL2
{ 9vVYZ}HC
bStop = true; z1YC%Y|R
for(int i=0;i<nStartPos.length;i++) 8cW]jm
fileSplitterFetch.splitterStop(); k-w._E <
fM8 :Nt$
cZHlW|$R
} K@?S0KMK
} ]C'r4Ch^
//负责部分文件的抓取 .-<o[(s
**FileSplitterFetch.java #%E~IA%
*/ ~>qcV=F^d,
package NetFox; ^srx/6X
t/y0gr tm6
wtRAq/
import java.io.*; xOEj+%M
import java.net.*; tF=96u_X
-o=qYkyLK
OvQG%D}P=
public class FileSplitterFetch extends Thread { 'jfI1 ]q
uS<&$JH
X\flx~
String sURL; //File URL JZai{0se
long nStartPos; //File Snippet Start Position '5{gWV`
long nEndPos; //File Snippet End Position m@TU2
int nThreadID; //Thread's ID eLl;M4d
boolean bDownOver = false; //Downing is over jg2>=}
boolean bStop = false; //Stop identical 8vchLl#
FileAccessI fileAccessI = null; //File Access interface g.z/%LpK
i5:fn@&
J/)Q{*`_
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException sdrE4-zd
{ QhN5t/Hr
this.sURL = sURL; Knn$<!>
this.nStartPos = nStart; M<Eg<*
this.nEndPos = nEnd; cp]\<p('A
nThreadID = id; V<(cW'zA/
fileAccessI = new FileAccessI(sName,nStartPos);//定位 NO;+:0n
} .,feRK>3
Vbz$dpT
;B!&( 50e
public void run() [{'` |
{ X&(1DE
while(nStartPos < nEndPos && !bStop) ]BX|G`CCc
{ I)n%aTfo8
QL
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try{ .hn"NXy
URL url = new URL(sURL); k`xPf\^tf
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Dy0RZF4_
httpConnection.setRequestProperty("User-Agent","NetFox"); i?||R|>;"'
String sProperty = "bytes="+nStartPos+"-"; dTS7l02
httpConnection.setRequestProperty("RANGE",sProperty); CSIW|R@
Utility.log(sProperty); 1[mX_ }K
v-g2k_o|
`Y8F}%i[
InputStream input = httpConnection.getInputStream(); q,kdr)-
//logResponseHead(httpConnection); /2WGo-
,uK }$l
$M#G;W5c
byte[] b = new byte[1024]; N9idk}T
int nRead; 7oK!!Qd^w
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) PWmFY'=
{ Pe~[qETv
nStartPos += fileAccessI.write(b,0,nRead); X`#vH8
//if(nThreadID == 1) REc69Y.k
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); THkg,*;:
} ~xkcQ{
-=@d2LY
_KLKa/3
Utility.log("Thread " + nThreadID + " is over!"); 8+^q9rLii
bDownOver = true; XeJn,=
//nPos = fileAccessI.write (b,0,nRead); MBp%TX!
} }~y i6!w'
catch(Exception e){e.printStackTrace ();} M;-PrJdyt
} 7S}NV7
} |!,;IoZ
1F{c5
SwXVa/9a"
//打印回应的头信息 <D%.'=%pZ
public void logResponseHead(HttpURLConnection con) PsaKzAg?
{ (gQP_Oa(
for(int i=1;;i++) Rcc9Tx(zvQ
{ xo a1='
String header=con.getHeaderFieldKey(i); #;z;8q
if(header!=null) o7;lR?
//responseHeaders.put(header,httpConnection.getHeaderField(header)); lvY[E9I0
Utility.log(header+" : "+con.getHeaderField(header)); W2&o'(P\
else +<a-;e{
break; `1{Y9JdQ
} gE\&[;)DB
} `-/-(v+ i
of659~EIW
Uc^eIa@
public void splitterStop() )%dxfwd6
{ j 4!$[h
bStop = true; x8 _f/2&
} L 4V,y>
%68'+qz
I() =Ufs5z
} L`NY^
aS=-9P;v
< KGq
/* E2K{9@i
**FileAccess.java X|y(B%:
*//文件访问(定位，写) vJ9I z
package NetFox; VddHK
import java.io.*; d<K2 \:P{}
r2yJ{j&s
xsu9DzPf&{
public class FileAccessI implements Serializable{ SO4?3wg7
G!dx)v
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 \Kr8k`f
RandomAccessFile oSavedFile; 2*Zk^h=
long nPos; G%iTL"6
)Fon;/p
,4:=n$e 0
public FileAccessI() throws IOException ' Dp;fEU$
{ o=J-Ju
this("",0); z36wWdRa6
} GXC,p(vbE
_NefzZWUJ
z_93j3#
public FileAccessI(String sName,long nPos) throws IOException ~=va<%{ U
{ ;NU-\<Q{
oSavedFile = new RandomAccessFile(sName,"rw"); `6$|d,m5
this.nPos = nPos; )Zf1%h~0r
oSavedFile.seek(nPos); 0vX4v)-^u
} xt_:R~/[
aD]! eP/)
0FSNIPx
public synchronized int write(byte[] b,int nStart,int nLen) "i#aII+T
{ % IHIXncv[
int n = -1; "!+gA&
try{ {ETM >
oSavedFile.write(b,nStart,nLen); Z_Wzm!:
n = nLen; `AYq,3V
} }@eIO|
catch(IOException e) Hz\@#
{ m/z,MT74*J
e.printStackTrace (); w 5 yOSz
} u 3^pQ6Q
b9-IrR4h
nr2 Q[9~
return n; _Jy7` 4B.
} )fHr]#v
N=AHS
k&2=-qgVR
} G54J'*Z
gg>QXui
(+c1.h
/* |BbzRis
**SiteInfoBean.java dvZH~mF
*/ (:aU"5M
package NetFox; dgL>7X=7
,jOJ\WXP
8[;vC$
public class SiteInfoBean { ,DZvBS
T'9ZR,{F
m>%b4M
private String sSiteURL; //Site's URL !$A/.;0$
private String sFilePath; //Saved File's Path 4qdoF_
private String sFileName; //Saved File's Name XEQTTD<
private int nSplitter; //Count of Splited Downloading File -8xf}v~u
Wl |5EY
As<B8e]
public SiteInfoBean() +x(#e'6p
{//nSplitter的缺省值为5 jMgXIK\
//default value of nSplitter is 5 GlnO8cAB
this("","","",5); yVII<ImqIH
} +? h}e
];Z6=9n
<XIIT-b[
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) /M_$4O;*@
{ $c9-Q+pZ
sSiteURL= sURL; XEgJ7h_
sFilePath = sPath; >~SS^I0
sFileName = sName; r/2= nE
this.nSplitter = nSpiltter; 5?lc%,-&
^Jp,&
)V\@N*L`ik
} z$e6T&u5B
V&w2pp0
7~ PL8
public String getSSiteURL() 2%dL96
{ &}r"Z?f)
return sSiteURL; fes s6=k
} H+4j.eVzZU
G 5;6q
?@ F2Kv
public void setSSiteURL(String value) 3''Sx8p
{ ]1|P|Jp
sSiteURL = value; hq)1YO
} {%f{U"m
X` zWw_i
gv''A"
public String getSFilePath() q.c)>=!.
{ Y !?'[t
return sFilePath; rW:krx9
} );$99t
TaN{xpo
rZ~w_DK*
public void setSFilePath(String value) 5&ku]l+
{ K]hp-QK<
sFilePath = value; $"r9U|6kk
} c-sjYJXKM*
CIjc5^Y2
{~3QBMx6
public String getSFileName() Nc;O)K!FH
{ 8R,<S-+v
return sFileName; p49]{2GXb
} =V[uXm
~SnUnNDm`
X2z<cJG|d@
public void setSFileName(String value) U ? +_\
{ x4oWZEd
sFileName = value; =]Vz=<
} |A%9c.DG.
K#0TD("
aQCu3T
public int getNSplitter() ieFl4hh[G
{ o4);5~1l
return nSplitter; 1~5DIU^
} qN $t_
0cd_l 2f#g
c$O8Rhx
public void setNSplitter(int nCount) ,o&C"sb
{ S#7YJ7 K"N
nSplitter = nCount; MUO<o
} \$ytmtf5
} <$A,Ex94
Y%pab/Y
-8Jw_
/* -U d^\Yy
**Utility.java o~Se[p
*/ tyu@aCK
package NetFox; 9R50,lsE
.Pb-{!$Ni
:DD<0
public class Utility { Lo%n{*if
WYw#mSp
l~c[}wv
public Utility() CMa6':~
{ ~r1pO#r-
&Y{^yb
}LzBo\
} JVZ-nHf(9
{.p.?
//线程睡眠 /jY u-H+C
public static void sleep(int nSecond) i"^>sk
{ a.Ho>(V/4
try{ ^*K=wE}AG
Thread.sleep(nSecond); r|Ui1f5
} (}: s[cs
catch(Exception e) P@{x@9kI
{ UUah5$Iy
e.printStackTrace (); i0vm00oT
} ag-A}k>v
} X8nos
eqbN_$>
//日志 #9vC]Gm
public static void log(String sMsg) RB5SK#z
{ (WM3(US|
System.err.println(sMsg); Dw-d`8*
} vgz`+Zj*S
"y1Iu
YR%iZ"`*+O
public static void log(int sMsg) +r:g}iR
{ iUx\3d,
System.err.println(sMsg); )t6]F6!_
} ~zVxprEf_
} hAGHb+:
YH&=cI@
z/@_?01T=
/* }A#IBqf5
**TestMethod.java g@.$P>Bh
*/ y.rN(
package NetFox; (eHyas %X
Vwkvu&4
/:{%X(8
public class TestMethod { O'y8q[2KE
i+_LKHQN
SQKhht`M
public TestMethod() dmFn0J-\
{ ///xx/weblogic60b2_win.exe NYm"I`5w
try{ !`DRJ)h
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ys[Li.s:
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); }F`|_8L*v)
SiteFileFetch fileFetch = new SiteFileFetch(bean); oMh$:jR$
fileFetch.start(); 0RUk^
} $|K d<wv
catch(Exception e){e.printStackTrace ();} i?00!t
A1WUK=P
d*(aue=
} 1b,a3w(:1
&!!*xv-z
5>k:PKHL
public static void main(String[] args) @u~S!(7.Wi
{ baxZ>KNi
new TestMethod(); )*')
} dC11kqqj
} 7Cgi&
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