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)); '6o`^u>
} hEv=T'*,K)
for(int i=0;i<nEndPos.length-1;i++) CP]S-o}yd
{ k'@7ZH
nEndPos = nStartPos[i+1]; z;y^t4 ^9
} ljYpMv.>xG
nEndPos[nEndPos.length-1] = nFileLength; aVppOxA
} -3G 4vRIo
} 97(Xu=tX
S$jV|xKB
<}EV*`w4
//启动子线程 B?;' lDz*
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; -Wlp=#9
for(int i=0;i<nStartPos.length;i++) ]>)u+|
{ C(V[wvL
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ~[|V3h4v
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), L$29L:
nStartPos,nEndPos,i); $(@o$%d
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); "?.'{,Q
fileSplitterFetch.start(); Q%& _On
} WxVn&c\
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ':4}O#
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); +}7Ea:K
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", >bfYy=/
nEndPos = " + nFileLength); RIy5ww}3|
// fileSplitterFetch[nPos.length-1].start(); [lNqT1%]
PTbA1.B
Pt6hGSo.
//等待子线程结束 EjR_-8@FK
//int count = 0; CxbSj,
//是否结束while循环 yn/?= ?0
boolean breakWhile = false; I*A0?{
3Q'[Ee2-3
}W:*aU
while(!bStop) \7Gg2;TA6o
{ ?Oy'awf_
write_nPos(); E0"10Qbi
Utility.sleep(500); I 1b
breakWhile = true; $J QWfGwR
,4^9cFVo
Iv$:`7|crX
for(int i=0;i<nStartPos.length;i++) q&XCX$N
{ M.ZEqV+k
if(!fileSplitterFetch.bDownOver) ]d@^i)2LF
{ 4F05(R8k
breakWhile = false; mje<d"bW
break; jM5_8nS&d
} lx\qp`w
} :+~KPn>w5
if(breakWhile) uY^v"cw/F
break; L`9TB"0R+
7 I_1 #O
M{`/f@z(
//count++; YfE>Pn'r
//if(count>4) qbS'|--wH
// siteStop(); k?3S
} }.0Bl&\UK
hi!L\yi
+>JdYV<?0
System.err.println("文件下载结束！"); C=fsJ=a5;
} 2R^O,Vu*W
catch(Exception e){e.printStackTrace ();} U'tE^W
} \Sg<='/{L;
=%!e(N'p
vB[~pQ;Z
//获得文件长度 (+|X<Bl:`
public long getFileSize() P @zz"~f7
{ q`XW5VV{K
int nFileLength = -1; !CVuw
try{ ?2{bKIV_
URL url = new URL(siteInfoBean.getSSiteURL()); `/z_rqJ0CL
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); G+0><,S
httpConnection.setRequestProperty("User-Agent","NetFox"); U1OFDXHG
v @:~mwy
Mr-DGLJ
int responseCode=httpConnection.getResponseCode(); =WC-Sj{I
if(responseCode>=400) <"W?<VjO
{ {3VZ3i
processErrorCode(responseCode); N;uUx#z
return -2; //-2 represent access is error !)N|J$FU
} Jlp<koy
-;^;2#](g
pe9@N9_5
String sHeader; h;-a`@rO ;
#O"
BT]ua]T+
for(int i=1;;i++) /RGNAHtIi
{ S=' wJ@?;
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); "< v\M85&
//Utility.log(in.readLine()); PocYFhWQ`
sHeader=httpConnection.getHeaderFieldKey(i); ?>af'o:
if(sHeader!=null) Z%m-HE:k
{ Z`Pd2VRp
if(sHeader.equals("Content-Length")) 'Gjq/L/x
{ h35Hu_c&
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 2#3^skj
break; p,F^0OU2}:
} in<}fAro6
} btH _HE
else ,_D"?o
break; piOXo=9H.
} $<|ocUC7
} LvJGvj
catch(IOException e){e.printStackTrace ();} m#f{]+6U
catch(Exception e){e.printStackTrace ();} q]\X~ 9#
pQMtj0(y
|ETiLR=&
Utility.log(nFileLength); GMW,*if8p
F[saP0 *
(vc|7DX M
return nFileLength; w%dL8k
} fQ+\;iAU
)4R:)-"f
B&Y_2)v
//保存下载信息（文件指针位置） T@[!A);
private void write_nPos() y{d^?(-
{ >O7~h[FN
try{ %+-C3\'
output = new DataOutputStream(new FileOutputStream(tmpFile)); Fl3#D7K
output.writeInt(nStartPos.length); g> S*<
for(int i=0;i<nStartPos.length;i++) Sm-wH^~KA
{ eKN$jlg
// output.writeLong(nPos); U7iuY~L
output.writeLong(fileSplitterFetch.nStartPos); ,RxYd6
output.writeLong(fileSplitterFetch.nEndPos); &\C [@_
} tNIlzR-
output.close(); ~u87H?
} in-C/m#
catch(IOException e){e.printStackTrace ();} re &E{
catch(Exception e){e.printStackTrace ();} >TjJA#
} gRJfX%*F
X|DO~{-au
QHt4",Ij
//读取保存的下载信息（文件指针位置） 7^*"O&y_al
private void read_nPos() PX(pX>
{ vuQ%dDxI
try{ Avlz=k1*
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); BxK^?b[E8
int nCount = input.readInt(); ,`A?!.K$
nStartPos = new long[nCount]; F^k.is
nEndPos = new long[nCount]; q2rUbU_A(
for(int i=0;i<nStartPos.length;i++) h*B|fy4K9U
{ nqVZqX@oE
nStartPos = input.readLong(); 6t'l(E +
nEndPos = input.readLong(); v%{.A)
} &w8)* T
input.close(); 7OCwG~_^
} U-kVNBs
catch(IOException e){e.printStackTrace ();} mqff]m
catch(Exception e){e.printStackTrace ();} evA/+F,&
} Va VN
$_H`
dsx]/49<
private void processErrorCode(int nErrorCode) `(6r3f~XJ
{ ?ULo&P[
System.err.println("Error Code : " + nErrorCode); )vg5((C
} {O<l[|Ip
ig LMv+{
/walu+]h
//停止文件下载 0[?ny`Y
public void siteStop() qn1255fB
{ me6OPc;:!
bStop = true; [%Bf< J<
for(int i=0;i<nStartPos.length;i++) +ISz?~8
fileSplitterFetch.splitterStop(); |2\{z{?
ofYlR|
`@[c8j7
} jcNT<}k C
} ae"]\a\&1o
//负责部分文件的抓取 'Jf^`ZT}
**FileSplitterFetch.java yme^b ;a
*/ =[\s8XH,
package NetFox; mC?i}+4>4R
~8"8w(CG*I
b^D$jY
import java.io.*; "s!7dKXI"
import java.net.*; *BuUHjTv
-V,v9h^
Yt|6 X:l
public class FileSplitterFetch extends Thread { :1t~[-h^
o?1;<gs
MX4]Vpv
String sURL; //File URL E9?phD
long nStartPos; //File Snippet Start Position A)%A!
long nEndPos; //File Snippet End Position =@k%&* Y?
int nThreadID; //Thread's ID &Ysosy*
boolean bDownOver = false; //Downing is over /Q~gU<
boolean bStop = false; //Stop identical 1x,[6H
FileAccessI fileAccessI = null; //File Access interface c@v{`d
dnV[ P
^v.,y3
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException U|g:`v7
{ Q{B}ef
this.sURL = sURL; GnP|x}YM
this.nStartPos = nStart; kcb.Wz~=
this.nEndPos = nEnd; JK.ZdY%
nThreadID = id; wdUBg*X8
fileAccessI = new FileAccessI(sName,nStartPos);//定位 n_3O-X(
} V+I|1{@i0
o] mD"3_
:1Q!$ m
public void run() &QhX1dT+
{ B<C*
while(nStartPos < nEndPos && !bStop) hEh}PX:
{ 5uxBK"q
=m5SK5vLKT
qhT@;W/X
try{ 1KjU ] r2
URL url = new URL(sURL); XoA+MuDzpo
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); >@"Oe
httpConnection.setRequestProperty("User-Agent","NetFox"); >3c@x
String sProperty = "bytes="+nStartPos+"-"; y#XbJuN/
httpConnection.setRequestProperty("RANGE",sProperty); ;]_o4e6\p
Utility.log(sProperty); jg?x&'u\)
}d<}FJ-,
3>Y6)
InputStream input = httpConnection.getInputStream(); {'U Rz[g
//logResponseHead(httpConnection); sP ls zC[
=b/L?dR.-
_1U1(^)
byte[] b = new byte[1024]; .nyfYa+
int nRead; U^Xm)lL
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 8>7&E-
{ C:Hoq(
nStartPos += fileAccessI.write(b,0,nRead); o`Ta("9^
//if(nThreadID == 1) H/Llj.-jg
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); E8-P"`Qba
} ",!1m7[wF
s>^dxF!+
$ aUo aI
Utility.log("Thread " + nThreadID + " is over!"); *6} N =Z
bDownOver = true; {#{DH?=^)u
//nPos = fileAccessI.write (b,0,nRead); p ZZc:\fJ
} Ps 8%J;
catch(Exception e){e.printStackTrace ();} *W kIq>
} |_yYLYH'
} 4n4?4BEn
{Lm~r+ U
;g~TWy^o
//打印回应的头信息 9k6r_G"
public void logResponseHead(HttpURLConnection con) 3"P }n
{ `(3/$%
for(int i=1;;i++) FHC\?Cg
{ Jej` ;I
String header=con.getHeaderFieldKey(i); 1Uqu>'
if(header!=null) AW,53\ 0
//responseHeaders.put(header,httpConnection.getHeaderField(header)); $_x^lr
Utility.log(header+" : "+con.getHeaderField(header)); 4 M(-xl?
else u{*SX k
break; zSFDUZ]A3
} 1n@8Kv
} +Xemf?
)LyojwY_g
Z"AQp _
public void splitterStop() rf$X>M=G
{ 3:C oZ
bStop = true; BN4_:
} et }T%~T
D)d~3`=#
*;fw%PW
} #cCL.p"]
^6_Cc
IqD_GL)Ms
/* %b"\bHH
**FileAccess.java uxzze~_+C
*//文件访问(定位，写) V7Mh-]
package NetFox; 1+U
import java.io.*; ?'<nx{!c
=hMY2D
mzf+Cu:`v
public class FileAccessI implements Serializable{ >b]S3[Q(
d{E}6)1=
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 J;f!!<l\
RandomAccessFile oSavedFile; mD/MJt5
long nPos; -Q U^c2
fOMvj%T@2
()3O=!
public FileAccessI() throws IOException G3{=@Z1
{ pe{;~-|6
this("",0); :P(K2q3
} [mPjP%{=@
>z.<u|r2
Ix(><#P
public FileAccessI(String sName,long nPos) throws IOException Y>&Ew*Y
{ txPIG/
oSavedFile = new RandomAccessFile(sName,"rw"); 44F`$.v96
this.nPos = nPos; q|LDo~H
oSavedFile.seek(nPos); *>+,(1Fz
} -%I2[)F<
[l8jRT=R
]Qe{e3p;
public synchronized int write(byte[] b,int nStart,int nLen) q.()z(M7
{ ]7/ b/J
int n = -1; U_{Ux2
try{ w&%~3Cz.
oSavedFile.write(b,nStart,nLen); FSRj4e1y1
n = nLen; G2^et$<{uU
} 5efpeu
catch(IOException e) bHI<B)=`
{ qVs\Y3u(
e.printStackTrace (); Usta0Ag
} c~v~2DM
@_LN3zP
? mhs$g>
return n; %zOh
} 1Zi,b
z1Ov|Q`
J;prC
} m-jHze`D3
q`G,L(
.YZgOJi
/* W mm4hkf
**SiteInfoBean.java po}F6m8bX
*/ BY]i;GVq
package NetFox; oaK%Ww6~
Hp(D);0+)
Tt>8?
public class SiteInfoBean { )<xypDQ
+nT'I!//
mB\C?=_
private String sSiteURL; //Site's URL 36n>jS&
private String sFilePath; //Saved File's Path `w.AQ?p@
private String sFileName; //Saved File's Name W'on$mB5<
private int nSplitter; //Count of Splited Downloading File 5IbJ
gp-T"l
J=dJsk
public SiteInfoBean() VG>vn`x>a
{//nSplitter的缺省值为5 PTS]7
//default value of nSplitter is 5 4Ua>Yw0
this("","","",5); ehA;i.n
} n\ Hs@.
|0,vQv
^xZ e2@
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) c c
{ |D.O6?v@
sSiteURL= sURL; Ap$y%6
sFilePath = sPath; .6~`Ubr}E
sFileName = sName; 1w"8~Z:UXV
this.nSplitter = nSpiltter; dC<LDxlv
|/ }\6L]
)RsM!}
} A!63p$VT;
gip/(/NX
9,]5v+
public String getSSiteURL() ?U7) XvQ
{ ^JR;epVJ
return sSiteURL; [\Qr. 2
} lHB) b}7E
q:8_]Qt
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public void setSSiteURL(String value) (.3'=n|kE
{ H@uE>
sSiteURL = value; l =IeJh
} V|MY!uV
/hv#CB>1x
N]YtLa,t
public String getSFilePath() z{]?h cY
{ 8%RI7Mg
return sFilePath; ~]L}p
} DDd|T;8
!8tS|C#2
o5aLUWi-
public void setSFilePath(String value) AAUyy :
{ T{vR,
sFilePath = value; lnbmoHv
} cyd~2\Kv~
{w^uWR4f
&GWkq>
public String getSFileName() 9j|gdfb%ml
{ [{&jr]w`|
return sFileName; xU9@$am
} o'%eI
(S^ck%]]a!
sP$Ks#/
public void setSFileName(String value) +K6szGP
{ K\Eo z]?
sFileName = value; /2NSZO
} ZYtiMBJ
RM*f|j
d @rs3Q1z
public int getNSplitter() D>wZ0p b-
{ %kU'hzLg
return nSplitter; .gYt0raSY
} ~S(^T9R
yqSY9EX7
^i_Iqph=
public void setNSplitter(int nCount) %(LvE}[RJ
{ hRTMFgO
nSplitter = nCount; fUcLfnr
} G{c#\?12C
} ;6DnId2Zh
S_8r\B[>P
5 d ;|=K
/* CB*/ =Y
**Utility.java !0fI"3P@r
*/ YL^Z4: p
package NetFox; _ 6:ww/
[!?wyv3
68x}w Ae
public class Utility { `Q9+k<
wRVD_?
y(8d?]4:_
public Utility() BXTN>d27
{ C{Blqf3V0
&(O06QL
NJ$e6$g)
} d=e{]MG(
AMk~dzNt
//线程睡眠 F";FG 0
public static void sleep(int nSecond) jzrt7p*k}
{ *]{=8zc2
try{ sb'p-Mj
Thread.sleep(nSecond); 0>Fqx{!heq
} G?[-cNdk
catch(Exception e) |s`Kd-'|q
{ FaWl,}]
e.printStackTrace (); j)6G7T|
} $Q4=37H+
} 8_iHVc;<
#>q[oie1e
//日志 l;5`0N?QO
public static void log(String sMsg) h[H%:743
{ 5bBCpNa
System.err.println(sMsg); 'bm:u
} qC.i6IL
{_as!5l
oeGS
public static void log(int sMsg) ]Wy.R6
{ cUC17z2D
System.err.println(sMsg); O0zi@2m?B
} m >hovikY*
} "GLYyC
t 2G1[j!
Gt5$6>A
/* +_-Y`O!Q
**TestMethod.java FpC~1Nau
*/ O3&|}:<
package NetFox; c85O_J
r8+*|$K
X}?ESjZJ
public class TestMethod { b.,$# D{p
z0;9SZ9
,0.|P`|w
public TestMethod() :Lc3a$qtx5
{ ///xx/weblogic60b2_win.exe taixBNv
try{ -7,vtd[h
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Y 0]Kl^\A
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); s8yCC#H"
SiteFileFetch fileFetch = new SiteFileFetch(bean); ?.~]mvOR
fileFetch.start(); 5{HtJ?sKc5
} Z3Gm
catch(Exception e){e.printStackTrace ();} ,?fN#gc :
+=Yk-nJ
bt0djJRw
} .?70=8{
| [p68v>
yIlV[_
public static void main(String[] args) nxD'r
{ X+d&OcO=q
new TestMethod(); df!+T0
} l~CZW*/
} $e>/?Ss
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