社区应用 最新帖子 精华区 社区服务 会员列表 统计排行 社区论坛任务 迷你宠物
  • 9834阅读
  • 0回复

http断点续传简单实现(java)

发帖
8
铜板
1641
人品值
95
贡献值
0
交易币
0
好评度
8
信誉值
0
金币
0
所在楼道
/* <7qM;) g  
**SiteFileFetch.java 0YKG`W  
*/ F"_SCA?9?  
package NetFox; -Y YQnN  
import java.io.*; z5?xmffB  
import java.net.*; U_+>4zdm  
XWk^$"  
Xln'~5~)  
public class SiteFileFetch extends Thread { \ /o`CV{O  
ie5"  
(%".=x-  
SiteInfoBean siteInfoBean = null; //文件信息Bean =2< >dM#`  
long[] nStartPos; //开始位置 75a3H`  
long[] nEndPos; //结束位置 h_J 'dJS  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 ,oR}0(^"\<  
long nFileLength; //文件长度 ,>)/y  
boolean bFirst = true; //是否第一次取文件 m}k rG  
boolean bStop = false; //停止标志 Rh%x5RFFc  
File tmpFile; //文件下载的临时信息 `.@N9+Aj  
DataOutputStream output; //输出到文件的输出流 <EJC.W WJa  
/" ,]J  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) R/iXO~/"J  
public SiteFileFetch(SiteInfoBean bean) throws IOException SH"O<c Dp  
{ HyB!8M|  
siteInfoBean = bean; &uC7W.|  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); 0q81H./3  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); A^G%8 )\  
if(tmpFile.exists ()) z.FO6y6L  
{ Vg0Rc t  
bFirst = false; M Su_*&j9T  
read_nPos(); R{/nlS5  
} vU::dr  
else J 5~bs*a8  
{ ">|fB&~A  
nStartPos = new long[bean.getNSplitter()]; ,?728pfw  
nEndPos = new long[bean.getNSplitter()]; iCx}v[;Ol  
} AFyf7^^k  
VCtj8hKDr  
kd2+k4@#  
ZPHB$]ri  
} ><%z~s  
)jvYJ9s  
PXWBc\  
public void run() 0P z"[  
{ 2 g,UdG  
//获得文件长度 yy@g=<okt\  
//分割文件 I;9>$?t[  
//实例FileSplitterFetch cZi/bIh  
//启动FileSplitterFetch线程 ftRf~5d2  
//等待子线程返回 dG\dGSZ\h  
try{ BTqY _9  
if(bFirst) !CUrpr/*  
{ ~'n3],o?  
nFileLength = getFileSize(); Q! WXFS  
if(nFileLength == -1) J'W6NitMr  
{ ?!KqDI  
System.err.println("File Length is not known!"); e~oI0%xl^  
} wP29 xV"5  
else if(nFileLength == -2) j8P=8w{  
{ R!5j1hMN`  
System.err.println("File is not access!"); 6cDe_v|,  
} O1V s!  
else !{jDZ?z{h  
{ qq G24**9v  
for(int i=0;i<nStartPos.length;i++) 7vZznN8e  
{ r$d,ChzQn?  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); zyTeF~_  
} 4@- 'p  
for(int i=0;i<nEndPos.length-1;i++) 0@k)C z[0;  
{ :@mb.' %*!  
nEndPos = nStartPos[i+1]; cyL"?vR*<  
} R^4JM,v9x`  
nEndPos[nEndPos.length-1] = nFileLength; }N dknut,  
} #!qa#.Yi  
} Xgou7x<  
3w6}%=)$8  
F$X"?fj  
//启动子线程 {FNmYneh?6  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 4-1=1)c*  
for(int i=0;i<nStartPos.length;i++) +G)L8{FY(  
{ hX;JMQ915  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), e'Njl?>3  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 5 o-WA1  
nStartPos,nEndPos,i); 7,X5]U&A<x  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); s|FfBG  
fileSplitterFetch.start(); Wb4+U;C^!'  
} .'aW~WR  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), XnR9/t  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); /x\{cHAt8J  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ",  UDl[  
nEndPos = " + nFileLength); ,ELbm  
// fileSplitterFetch[nPos.length-1].start(); \iVb;7r)9:  
vr/*z euA  
oK\{#<gCZ  
//等待子线程结束 ai0am  
//int count = 0; Q*&k6A"jx  
//是否结束while循环 3 vr T`  
boolean breakWhile = false; W~b->F  
f-$%Ck$%,  
`3GYV|LeQ  
while(!bStop) 3HCH-?U5  
{ <u`m4w  
write_nPos(); Q0l[1;$#  
Utility.sleep(500); {{N*/ E^  
breakWhile = true; J%r$jpd'  
3M~*4  
J?DJA2o  
for(int i=0;i<nStartPos.length;i++) 4TX~]tEyky  
{ "0Ca;hSLM2  
if(!fileSplitterFetch.bDownOver) IHC {2 ^  
{ ?Pbh&!  
breakWhile = false; `?P)RS30  
break; m}`!FaB #  
} nz+k ,  
} nymro[@O~  
if(breakWhile) N #C,q&;  
break; 'qoDFR\v  
4+?d0  
tg5G`P5PJ  
//count++; ~IQ3B $4H&  
//if(count>4) {XR 3L'X  
// siteStop(); NW?.Ge.!P  
} xQA6!j  
zw ,( kv  
Xlg 0u.  
System.err.println("文件下载结束!"); >_esLsPWh]  
} "Zr+>a  
catch(Exception e){e.printStackTrace ();} Z @f4=  
} ,]FcWx \u  
U?/C>g%/PI  
)b\89 F  
//获得文件长度 e:`d)GE  
public long getFileSize() #"&<^  
{ 0[L)`7  
int nFileLength = -1; Wks?9 )Is  
try{ LKX; ^  
URL url = new URL(siteInfoBean.getSSiteURL()); 5-[bdI  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); nNj<!}HvV  
httpConnection.setRequestProperty("User-Agent","NetFox"); *gGL5<%T:  
VelR8tjP  
ais@|s;  
int responseCode=httpConnection.getResponseCode(); crvq]J5  
if(responseCode>=400) <?h,;]U  
{ dAba'|Y  
processErrorCode(responseCode); ,2>nr goM  
return -2; //-2 represent access is error 1[4 2f#  
} e]5 n4"]D)  
E=3UaYr  
%Bxp !Bj  
String sHeader; D2N<a=#  
5oOF|IYi  
jVdRy{MH  
for(int i=1;;i++) ~Y)h[  
{ t?l0L1;  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ))9w)A@  
//Utility.log(in.readLine()); JnodDH ?  
sHeader=httpConnection.getHeaderFieldKey(i); <&47W  
if(sHeader!=null) <0sT  
{ GI. =\s  
if(sHeader.equals("Content-Length")) B QxU~s  
{ 3{/[gX9  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); ))NiX^)8^  
break; SJ0IEPk  
} G _1`NyI  
} hf('4^  
else V(#z{!  
break; P70]Ju  
} .S{>?2  
} oj$^87KX  
catch(IOException e){e.printStackTrace ();} IVY{N/ 3|  
catch(Exception e){e.printStackTrace ();} 3q}fDM(@J  
rb_FBa%  
zt3y5'Nk  
Utility.log(nFileLength); 1w~@'ZyU  
7c8A|E0\mF  
  mN^/  
return nFileLength; #)BbW40f6  
} ^.?5!9U  
?7|6jTIs  
u6#FG9W7  
//保存下载信息(文件指针位置) hW Va4  
private void write_nPos() P(|+1$#[  
{ 5&Vp(A[m[  
try{ Et0[HotO  
output = new DataOutputStream(new FileOutputStream(tmpFile)); n 97pxD_74  
output.writeInt(nStartPos.length); -F338J+J24  
for(int i=0;i<nStartPos.length;i++) ]>_Ie?L)<  
{ 3*<?'O7I0  
// output.writeLong(nPos); =" Sb>_  
output.writeLong(fileSplitterFetch.nStartPos); |A/)b78'u  
output.writeLong(fileSplitterFetch.nEndPos); 7Z7e}| \W  
} 9vL n#_  
output.close(); + r<d z  
} /&jh10}H  
catch(IOException e){e.printStackTrace ();} bw[s<z|LKA  
catch(Exception e){e.printStackTrace ();} D *Hy 2eZ.  
} mh7JPbX|  
rAwuWM@BIg  
=ICakh!TO  
//读取保存的下载信息(文件指针位置) d) i64"  
private void read_nPos() Jv[c?6He  
{ l2|[  
try{ 'jr[ ?WQ  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); WJA0 `<~  
int nCount = input.readInt(); -qW[.B  
nStartPos = new long[nCount]; b,r{wrLe)  
nEndPos = new long[nCount]; PN"s ^]4  
for(int i=0;i<nStartPos.length;i++) 1RM@~I$0  
{ h,!`2_&UQ  
nStartPos = input.readLong(); </B<=tc  
nEndPos = input.readLong(); At$[&%}  
} Xc H_Y  
input.close(); zho$g9*  
} 4apy{W  
catch(IOException e){e.printStackTrace ();} D.:6X'hp  
catch(Exception e){e.printStackTrace ();} kh5VuXpe  
} NG\g_^.M  
)wdTs>W7  
s+ a} _a:  
private void processErrorCode(int nErrorCode) 1/J3 9Y~+  
{ X :wfmb  
System.err.println("Error Code : " + nErrorCode); 6t!PHA  
} chs] ,7R  
lFT` WO  
qC:QY6g$N  
//停止文件下载 d,+a}eTP'  
public void siteStop() 5u=$m^@{  
{ nA4PY]  
bStop = true; [#mRlL0yk  
for(int i=0;i<nStartPos.length;i++) AdGDs+at,  
fileSplitterFetch.splitterStop(); :JD*uu  
sn-P&"q  
!E.CpfaC  
} b-Xc6f  
} /]>8V'e\  
//负责部分文件的抓取 F`8B PWUY  
**FileSplitterFetch.java E=$li  
*/ %k =c9ll@:  
package NetFox; >p?Vv0*  
hj+iB,8  
7M,(!*b  
import java.io.*; }[mLtv%&  
import java.net.*; 9?38/2kX4  
^_5t5>  
}BN!Xa  
public class FileSplitterFetch extends Thread { C.N#y`g  
:/XWk %  
q .s'z}  
String sURL; //File URL 7N4)T'B  
long nStartPos; //File Snippet Start Position Boj#r ,x  
long nEndPos; //File Snippet End Position aNDpCpy  
int nThreadID; //Thread's ID /|LQ?n  
boolean bDownOver = false; //Downing is over h\lyt(.s  
boolean bStop = false; //Stop identical :D:Y-cG*n<  
FileAccessI fileAccessI = null; //File Access interface FXG,D J:  
=x3T+)qCNX  
%}[/lIxaE  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException # ~(lY}  
{ %@MO5#)NI  
this.sURL = sURL; f~ P~%  
this.nStartPos = nStart; a%*W( 4=Y  
this.nEndPos = nEnd; 0u?Vn N<  
nThreadID = id; rk8Cea  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 awU&{<,=g  
} oZ\zi> Y,  
Vu5Djx'  
DDBf89$\  
public void run() %G/(7l[W  
{ pF<KhE*V  
while(nStartPos < nEndPos && !bStop) `dJ?j[P,p  
{ S5/p3;O\c  
qlm7eS"sy  
q_86nvB<  
try{ oCSJ<+[(C  
URL url = new URL(sURL); &6&$vF65c  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); l&{+3aC:  
httpConnection.setRequestProperty("User-Agent","NetFox"); @B9O*x+n:  
String sProperty = "bytes="+nStartPos+"-"; Pj ^O8  
httpConnection.setRequestProperty("RANGE",sProperty); ~9Cw5rwH<;  
Utility.log(sProperty); on.m '-s  
:V~ AjV  
-'rb+<v  
InputStream input = httpConnection.getInputStream(); *0/%R{+S  
//logResponseHead(httpConnection); +ux170Cd3  
rYO~/N  
vl>_;} W7  
byte[] b = new byte[1024]; ,% *Jm  
int nRead; iD) P6"  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) &I7T ?  
{ >uR;^B5m  
nStartPos += fileAccessI.write(b,0,nRead); ZsN3 MbY  
//if(nThreadID == 1) 6ANA oWg*  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); $D;-;5[-/r  
} 8I<LZ{a10  
L8?;A9pc()  
|vY|jaV}  
Utility.log("Thread " + nThreadID + " is over!"); \me-#: Gu  
bDownOver = true; I>:.fHvUC  
//nPos = fileAccessI.write (b,0,nRead); >K*TgG6!X  
} [E;~Y_l  
catch(Exception e){e.printStackTrace ();} !m?W+ z~J  
} sfR0wEqI  
} J~lKN <w  
3Y=uBl  
(|sqN8SbA  
//打印回应的头信息 MrhJk  
public void logResponseHead(HttpURLConnection con) &24>9  
{ 4 IXa[xAm  
for(int i=1;;i++) $j&2bO 5M  
{ lB(P+yY,/'  
String header=con.getHeaderFieldKey(i); I 8 Ls_$[  
if(header!=null) C8$/z>tQ  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); G$1gk^G's  
Utility.log(header+" : "+con.getHeaderField(header)); [-2Tj)P C  
else Y*YV/E.  
break; S<>u  
} @pV&{Vp  
} VV"1IR  
Eg0qY\'  
=z9FjK  
public void splitterStop() M 9/J!s  
{ 3`{[T17  
bStop = true; 5mg] su&#  
} 4n/CS AT1  
7F8>w 7Y]  
6mC% zXR5  
} v,Yz\onB^  
aKw7m= {  
3/*<i  
/* kx07Ium  
**FileAccess.java o & kgRv[  
*//文件访问(定位,写) kXW$[R  
package NetFox; bf$4Z: Y  
import java.io.*; Pql;5 ~/  
;"+]bne~  
W(jP??up  
public class FileAccessI implements Serializable{ tkf^sGgNO  
7_ao?}g  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 7hl,dtn7  
RandomAccessFile oSavedFile; S3&lkN5  
long nPos; i`EG80\[Z  
k>!A~gfP~  
(zhi/>suG  
public FileAccessI() throws IOException {KM5pK?,BJ  
{ g:fzf>oQ>p  
this("",0); Rx.dM_S  
} @1+({u#B  
$s!2D"wl n  
ZR@PqS+O/  
public FileAccessI(String sName,long nPos) throws IOException /Pgc W  
{ dS~#Lzm  
oSavedFile = new RandomAccessFile(sName,"rw"); qb >mUS  
this.nPos = nPos; Oh/2$72  
oSavedFile.seek(nPos); c~{)vL0K  
} w$[ck=  
R^tDL  
<h mRr  
public synchronized int write(byte[] b,int nStart,int nLen) Qj(|uGqm3  
{ ljw>[wNv  
int n = -1; i2 m+s;  
try{ <ly.l]g  
oSavedFile.write(b,nStart,nLen); ,-_\Y hY>  
n = nLen; VXIB9 /*i  
} -+Ab[  
catch(IOException e) fv?vfI+m  
{ a^.5cJ$]  
e.printStackTrace (); e$=0.GWT  
} U8icP+Y  
@/0-`Y@?  
FvV:$V|  
return n; K9+%rqC.|`  
} !%Qm{R  
Uh8c!CA8:\  
WR@TH bU  
} !(-S?*64l  
9 M!J7 W  
1"P^!N  
/* B kWoK/f4  
**SiteInfoBean.java C J#1j>  
*/ 3F|#nq  
package NetFox; k\`~v$R3  
P *zOt]T  
sqP (1|9  
public class SiteInfoBean { ~Bs=[TNd[  
mu#  a  
@O Rk  
private String sSiteURL; //Site's URL Rw#4 |&  
private String sFilePath; //Saved File's Path + 4*jO5EZ  
private String sFileName; //Saved File's Name Jx_BjkF  
private int nSplitter; //Count of Splited Downloading File AQa;D2B$  
pQf5s7  
tNbZ{=I>  
public SiteInfoBean() O0Sk?uJ <  
{//nSplitter的缺省值为5 N#"(  
//default value of nSplitter is 5 YqSkz|o}m  
this("","","",5); ;R8pVj!1f  
} ofIw7D*h  
)S 2GPn7  
0281"aO  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) mcFJ__3MAV  
{ z),@YJU"z  
sSiteURL= sURL; 0.}WZAYy~  
sFilePath = sPath; F2 #s^4Ii  
sFileName = sName; JXA!l ?%  
this.nSplitter = nSpiltter; B8sc;Z.  
! >l)*jN8  
#`(-Oj2hH  
} 27q=~R}  
F.[E;gOTo  
b6y/o48  
public String getSSiteURL() ?z$^4u3  
{ "fTW2D74  
return sSiteURL; OX!<{9o  
} 0v/}W(  
PA_54a9/<  
qZz?i  
public void setSSiteURL(String value) 7g&"clRGO  
{ VA^yv1We  
sSiteURL = value; c&AJFED]<  
} dnW#"  
? f\ ~:Gm/  
48 n5Y~YS  
public String getSFilePath() ap y#8]  
{ GjD^\d/  
return sFilePath; B{ptP4As-  
} ljw(cUM  
}> pNf  
/ 8 0Q  
public void setSFilePath(String value) 8'}D/4MUr  
{ Ga M:/.  
sFilePath = value; j{?ogFfi  
} td"D&1eQ@  
p|f5w"QcH  
Y_SB3 $])  
public String getSFileName() <<5x"W(,  
{ gf\F%VmSN  
return sFileName; ^^FqN;  
} dbG5Cf#K\  
ys~oJb~  
io1hUZ  
public void setSFileName(String value) s=BJ7iU_68  
{ a2!;$B%  
sFileName = value; s`63 y&Z[  
} r]<?,xx [  
}F<=  
)@,zG(t5;  
public int getNSplitter() V[RsSZx =  
{ KW 78J~u+  
return nSplitter; L55VS:'  
} =(cfo_B@K  
6Ex 16  
EjDr   
public void setNSplitter(int nCount) ?Tr\r1s]  
{ %~$coZY^  
nSplitter = nCount; OB5t+_ s  
} XKQ\Ts2<k  
} 4Y `=`{Q  
W#sCvI@   
=`W#R  
/* I/`\>Hk  
**Utility.java $z[r (a^a  
*/ *Al`QEW  
package NetFox; g* DBW,  
3U!#rz"  
/4wPMAlb  
public class Utility { l37) Q  
H5X.CcI&}  
7S.E,\Tws  
public Utility() m(rd\3d  
{ eH' J  
x$+g/7*  
<S@XK%  
} j3&tXZ;F  
sB+ B,DF  
//线程睡眠 RQQ\y`h`  
public static void sleep(int nSecond) O&@pi-=o  
{ -kkp Ew\  
try{ yDmx)^En  
Thread.sleep(nSecond); j~C-T%kYa  
} /P koqA,  
catch(Exception e) a=&{B'^G  
{ 1%Su~Z"W>  
e.printStackTrace (); i{2ny$55h  
} Gq0Q}[53  
} ,f)#&}x*2+  
TJ+,G4z  
//日志 >^ TcO  
public static void log(String sMsg) {}DoRp q=  
{ +V;@)-   
System.err.println(sMsg); }+dDGFk  
} [iGL~RiXtn  
<&MY/vV  
MYMg/>f[  
public static void log(int sMsg) :=e"D;5  
{ _,bDv`>Ra  
System.err.println(sMsg); C<yjGt VD  
} G^&P'*  
} klxNGxWAX  
v)s; wD  
Gzkvj:(V  
/* cTu"Tu\Qw  
**TestMethod.java 45U!\mG  
*/ ? uu,w  
package NetFox; AZf$XHP2  
$c1xh.  
=.\PG [  
public class TestMethod { ?*dt JL  
o3,}X@p  
\SyG#.$  
public TestMethod() o%)38T*n3  
{ ///xx/weblogic60b2_win.exe [I2vg<my  
try{ YLehY  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ;Yu|LaI\<m  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); s~g0VNu Y  
SiteFileFetch fileFetch = new SiteFileFetch(bean); R@A"U[*  
fileFetch.start(); GFfZ TA  
} 2 i97  
catch(Exception e){e.printStackTrace ();} <}('w/  
*RJiHcII  
~jDf,a2  
} 5h@5.-}  
&at>sQ'  
4H_QQ6  
public static void main(String[] args) f <pJ_  
{ ?G<.W[3  
new TestMethod(); [iUy_ C=qp  
} 7QM1E(cMg  
}  Vl`!6.F3  
点击下载更多相关资料
评价一下你浏览此帖子的感受

精彩

感动

搞笑

开心

愤怒

无聊

灌水
描述
快速回复

您目前还是游客,请 登录注册
批量上传需要先选择文件,再选择上传
认证码:
验证问题:
10+5=?,请输入中文答案:十五