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
  • 8287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
/* hbZ]DRg  
**SiteFileFetch.java Gp 8%n  
*/  ywQ>T+  
package NetFox; iJ8 5okv'  
import java.io.*; 8PN/*Sa  
import java.net.*; | aAu 4   
1yFVF  
Z)V m,ng  
public class SiteFileFetch extends Thread { 3o).8b_3g  
Vgh;w-a  
Z)JJ-V!  
SiteInfoBean siteInfoBean = null; //文件信息Bean $x5,Oen  
long[] nStartPos; //开始位置 ~Onj| w7  
long[] nEndPos; //结束位置 72i ]`   
FileSplitterFetch[] fileSplitterFetch; //子线程对象 -|1H-[Y(  
long nFileLength; //文件长度 ]YQ!i@Y  
boolean bFirst = true; //是否第一次取文件 f+ }Rj0A  
boolean bStop = false; //停止标志 ;HKb  
File tmpFile; //文件下载的临时信息 4blw9x N  
DataOutputStream output; //输出到文件的输出流 It5U=PU  
M lv  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) KOQiX?'  
public SiteFileFetch(SiteInfoBean bean) throws IOException Z.Otci>J  
{ {c 82bFiv  
siteInfoBean = bean; ,]:vk|a#;  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); ]'L#'"@  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); 96NZ rT  
if(tmpFile.exists ()) q5Bj0r[/o  
{ ,5Vc  
bFirst = false; >rbHpLm1`  
read_nPos(); 8Ce|Q8<8]  
} y15 MWZ  
else [>P9_zID  
{ $A4rdhvd  
nStartPos = new long[bean.getNSplitter()]; jb~W(8cj  
nEndPos = new long[bean.getNSplitter()]; L&gC  
} NZu\ Ae  
`&3hfiI}  
For`rfR  
|E& F e8  
} d65fkz==A)  
X2RM*y|  
\+?>KpE,b  
public void run() ZsgJ6 Y  
{ ( M > C  
//获得文件长度 S1Z~-i*w  
//分割文件 dkHye>  
//实例FileSplitterFetch ?&ow:OH+  
//启动FileSplitterFetch线程 G,{=sFX  
//等待子线程返回 OpNTyKbaD  
try{ S":55YQev!  
if(bFirst) #!A'6SgbkM  
{ ;~A-32;Y4  
nFileLength = getFileSize(); Fwu:x.(  
if(nFileLength == -1) iRbTH}4i  
{ Lip(r3  
System.err.println("File Length is not known!"); U<pG P  
} pCB^\M%*  
else if(nFileLength == -2) t K $r_*  
{ N5ph70#y3  
System.err.println("File is not access!"); 3SI~?&HU!/  
} +hUS sR&  
else xSf&*wLE  
{ rE&` G[(b  
for(int i=0;i<nStartPos.length;i++) T<jo@z1UL  
{ P#0U[`ltK  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); Moldv x=M  
} A`5/u"]*D  
for(int i=0;i<nEndPos.length-1;i++) WfdM~k\  
{ ?{)sdJe  
nEndPos = nStartPos[i+1]; /Zzb7bHLK  
} IIn sq  
nEndPos[nEndPos.length-1] = nFileLength; v+), uj  
} 6w?l I  
} bNH72gX2Yh  
tom1u>1n  
P' ";L6h  
//启动子线程 @]{+9m8G@  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; IIZu&iZo\  
for(int i=0;i<nStartPos.length;i++) wsfN \6e  
{ zL^`r)H  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Kyr3)1#J  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), O_E\(So  
nStartPos,nEndPos,i); 0x N1Xm0d  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); u{asKUce\  
fileSplitterFetch.start(); 6\+ ZTw  
} jD<fu  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M1Frn n  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); lc:dKGF6  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", (plsL   
nEndPos = " + nFileLength); E43Gk!/|(  
// fileSplitterFetch[nPos.length-1].start(); Wl29xY}`{!  
We8n20wf<  
@W_=Z0]  
//等待子线程结束 o+w G6 9  
//int count = 0;  WR;)  
//是否结束while循环 Gz_[|,i  
boolean breakWhile = false; &7fwYV  
(G E)  
u|G&CV#r  
while(!bStop) vqeWt[W v  
{ XEUy,>mR  
write_nPos(); S-5|t]LV  
Utility.sleep(500);  9Kpzj43  
breakWhile = true; F0D7+-9[  
J{69iQ  
Yn~N;VUA  
for(int i=0;i<nStartPos.length;i++) 8et*q3D7`  
{ brdfj E8  
if(!fileSplitterFetch.bDownOver) , GU|3  
{ un&Z' .   
breakWhile = false; ~xp(k  
break; SU` RHAo  
} >u-6,[(5X*  
} K> rZJ[a  
if(breakWhile) P3W<a4 ==  
break; ^zfO=XN  
sC< B  
nt5x[xa  
//count++; C.#\ Pz0  
//if(count>4) US.7:S-r"  
// siteStop(); q^I/  
} h1A/:/_M6  
pBbfU2p  
$:4* ?8 K2  
System.err.println("文件下载结束!"); 2#XYR>[  
} Jc3Z1Tt  
catch(Exception e){e.printStackTrace ();} hoDE*>i  
} +H4H$H  
NDqvt$  
j "^V?e5  
//获得文件长度 2!Gb4V  
public long getFileSize() O^2@9 w  
{ hoOT]Bsn  
int nFileLength = -1; M'gL_Xsei  
try{ ~vGX(8N  
URL url = new URL(siteInfoBean.getSSiteURL()); T'K6Q cu  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); $;V?xZm[  
httpConnection.setRequestProperty("User-Agent","NetFox"); zxo" +j4Ym  
+n>_NVe  
! D \u2h  
int responseCode=httpConnection.getResponseCode(); h(>eHP  
if(responseCode>=400) P<OSm*;U:  
{ f ecV[  
processErrorCode(responseCode); 7gx 7NDt  
return -2; //-2 represent access is error qs|{  
} k%gO  
O/N@ Gz[g%  
V~~4<?=A  
String sHeader; >Av[`1a2F  
p-S&Wq  
 45qSt2  
for(int i=1;;i++) K.R4.{mo  
{ f)b+>!  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); Dus [N< w  
//Utility.log(in.readLine()); A@?Rj  
sHeader=httpConnection.getHeaderFieldKey(i); ?b,x;hIO  
if(sHeader!=null) jfOqE*frl!  
{ 5.TeH@(  
if(sHeader.equals("Content-Length")) 3+uCTn0%  
{ C@ns`Eh8w  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); BB.^[:,dA  
break; *^@{LwY\M  
} d'okXCG  
} d$?sS9"8(  
else %Ums'<xJ  
break; !,0%ZG}]7  
} :,f~cdq=  
} ;dR4a@  
catch(IOException e){e.printStackTrace ();} ALO0yc  
catch(Exception e){e.printStackTrace ();} })#SjFq<V  
iL6Yk @  
,P.yl~'Al  
Utility.log(nFileLength); $-Yq?:  
Af`qe+0E  
6`JY:~V"  
return nFileLength; Ob~7r*q  
} bZKlQ<sI  
6]D%|R,Q#}  
h@H8oZ[  
//保存下载信息(文件指针位置) IHs^t/;Iv  
private void write_nPos() F^/b!)4X  
{ MJ..' $>TC  
try{ )zK6>-KWA  
output = new DataOutputStream(new FileOutputStream(tmpFile)); CBrC   
output.writeInt(nStartPos.length); A7c*qBt  
for(int i=0;i<nStartPos.length;i++) <5t2+D]]}  
{ kM;fxR:-  
// output.writeLong(nPos); u;/5@ADW  
output.writeLong(fileSplitterFetch.nStartPos); V0 O6\)/.  
output.writeLong(fileSplitterFetch.nEndPos); @}oY6cW;B*  
} .G~Y`0  
output.close(); _s%;GWj  
} GLpl  
catch(IOException e){e.printStackTrace ();} x[dR5  
catch(Exception e){e.printStackTrace ();} YK V?I   
} ^fq^s T.$  
v{44`tR   
[/+}E X  
//读取保存的下载信息(文件指针位置) = 9K5f# ;e  
private void read_nPos() ` v"p""_H  
{ 5IJm_oy  
try{ 4b/>ZHFOF;  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); m.g2>r`NU  
int nCount = input.readInt(); [(kC/W)!  
nStartPos = new long[nCount]; QrSF1y'd  
nEndPos = new long[nCount]; , |lDR@  
for(int i=0;i<nStartPos.length;i++) $E,,::oJ  
{ ,Qb(uirl]  
nStartPos = input.readLong(); g7-*WN<  
nEndPos = input.readLong(); J4l \  
} vS1#ien#  
input.close(); 02RZ>m+  
} CUI\:a-   
catch(IOException e){e.printStackTrace ();} K4w#}gzok  
catch(Exception e){e.printStackTrace ();} N7l`-y  
} 6M^NZ0~J  
_B6W:k|-7l  
W3E7y?  
private void processErrorCode(int nErrorCode) h|Ah\P?o  
{ D9 \!97  
System.err.println("Error Code : " + nErrorCode); !$Whftg  
} 0tS < /G8  
Pz77\DpFi  
NQu .%=  
//停止文件下载 (aUdPo8H^  
public void siteStop() d [f,Nu'  
{ aJ3.D  
bStop = true; }c?W|#y`.o  
for(int i=0;i<nStartPos.length;i++) *2^+QKDG  
fileSplitterFetch.splitterStop(); S"Z.M _  
5oTj^W8M(  
;_dOYG1  
} TO5#iiM)  
} (`cXS5R  
//负责部分文件的抓取 !V O^oD7  
**FileSplitterFetch.java 'L5ih|$>  
*/ *I<L1g%9d  
package NetFox; BTAt9Z8qK  
3vC"Q!J&  
4 >`2vb  
import java.io.*; /73ANQ"  
import java.net.*; C &~s<tcn  
hYSzr-)  
Pu0 <Clh  
public class FileSplitterFetch extends Thread { ~zO>Q4-k  
sBq6,Iu  
K*sav?c  
String sURL; //File URL ZFFKv  
long nStartPos; //File Snippet Start Position O =gv2e  
long nEndPos; //File Snippet End Position ]*v [6 +  
int nThreadID; //Thread's ID GC3WB4iY@U  
boolean bDownOver = false; //Downing is over  SCq:jI  
boolean bStop = false; //Stop identical }v4T&/vt-  
FileAccessI fileAccessI = null; //File Access interface I3^}$#>  
<_ruVy0]  
{^*K@c  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException j0uu* )Rk  
{ u5O`|I@R  
this.sURL = sURL; S9kA69O  
this.nStartPos = nStart; N?j#=b+D  
this.nEndPos = nEnd; lK"m|Z  
nThreadID = id; $VNj0i. Pr  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 yR$ld.[uf  
} jzb%?8ZJ  
|6o!]~&e$1  
L )53o!  
public void run() (kmrWx= $  
{ !4vepa}Y  
while(nStartPos < nEndPos && !bStop) n]x%xnt  
{ `)TuZP_)  
mzm{p(.  
WvN{f*  
try{ i1JVvNMQ,  
URL url = new URL(sURL); 0?Bv zfb  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); >)*0lfxTZ  
httpConnection.setRequestProperty("User-Agent","NetFox"); ]WvV*FL9D3  
String sProperty = "bytes="+nStartPos+"-"; S>;+zVF]  
httpConnection.setRequestProperty("RANGE",sProperty); ,TlYQ/j%h  
Utility.log(sProperty); 1haNpLfS>  
o XFo  
epGC Ta  
InputStream input = httpConnection.getInputStream(); IcJQC  
//logResponseHead(httpConnection); =OamN7V=  
&B?*|M`)k  
F&u)wI'  
byte[] b = new byte[1024]; wB+X@AA  
int nRead; ;2}wrX  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ;)23@6{R%  
{ $i|d=D&t  
nStartPos += fileAccessI.write(b,0,nRead);  wzf  
//if(nThreadID == 1) pB:/oHV  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 0Z1';A3  
} Id^)WEK4  
,(;]8G-Yj  
:y1,OR/k  
Utility.log("Thread " + nThreadID + " is over!"); #5yz~&  
bDownOver = true; HAmAmEc,  
//nPos = fileAccessI.write (b,0,nRead); FjV)QP H  
} V/Q/Ujgg  
catch(Exception e){e.printStackTrace ();} F10TvJ U  
} [9d4 0>e  
} `Rx\wfr}  
%V|n2/O Y  
/2>.*H_2  
//打印回应的头信息 NnRX0]  
public void logResponseHead(HttpURLConnection con) &a!MT^anA~  
{ !X4m6gRaP  
for(int i=1;;i++) CLgfNrW~  
{ E RjMe'q4  
String header=con.getHeaderFieldKey(i); k"F\4M  
if(header!=null) 2#Du5d  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); NCivh&HR  
Utility.log(header+" : "+con.getHeaderField(header)); dZ|x `bIgs  
else $&X-ay o  
break; Dg}$;PK  
} Mhu|S)hn  
} N oRPvFv  
oH;9s-Be  
s<{) X$  
public void splitterStop() F% z$^ m-  
{ _6.Y3+7I  
bStop = true; yY_#fJj  
}   bKt4  
"sYZ3  
|f3 :9(p  
} Z '~Ie~  
bD`h/jYv  
+1nzyD_E  
/* 'x<o{Hi"\B  
**FileAccess.java (W |;gQ  
*//文件访问(定位,写) b6! 7 j  
package NetFox; 0M!GoqaA  
import java.io.*; ]Jo}F@\g  
@a (-U.CZ  
r"!xI  
public class FileAccessI implements Serializable{ <UwYI_OX  
6 IRa$h>H  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 @plh'f}  
RandomAccessFile oSavedFile; M{g.x4M@W  
long nPos; zy`T! $  
3z% W5[E)  
`(M0I!t  
public FileAccessI() throws IOException 0i(c XB  
{ ^s\T<;  
this("",0); Y+{jG(rg.F  
} NUFW SL>  
_&N}.y)+t  
rV}&G!V_t  
public FileAccessI(String sName,long nPos) throws IOException v8K`cijSS  
{ Lk.tEuj=82  
oSavedFile = new RandomAccessFile(sName,"rw"); Y|S>{$W  
this.nPos = nPos; :,V&P_  
oSavedFile.seek(nPos); Jwpc8MQ  
} %+oqAY m+s  
Hu+GN3`sx^  
$f=6>Kn|^]  
public synchronized int write(byte[] b,int nStart,int nLen) ~l}\K10L*  
{ !8&EkXTw,  
int n = -1; [lGxys)J  
try{ B+z>$6  
oSavedFile.write(b,nStart,nLen); m qwJya  
n = nLen; K[S)e!\.  
} &WZ&Tt/)/  
catch(IOException e) z"-oD*ICw  
{ PYTwyqS  
e.printStackTrace (); ;;+h4O )  
} #gVWLm<  
?JBA`,-  
M(vX.kF  
return n; W;?e@}  
} OZEbs 7  
intl?&wC  
xlH3t&i7  
} :!JQ<kV  
mbns%%GJU  
K>TEt5  
/* 0 \V)DV.i  
**SiteInfoBean.java e,MgR\F}  
*/ tX6_n%/L  
package NetFox; n=?wX#rEC#  
*fz#B/ _o  
10xza=a  
public class SiteInfoBean { a(LtiO  
FKUo^F?z  
Bj GfUQ  
private String sSiteURL; //Site's URL q:=jv6T#  
private String sFilePath; //Saved File's Path 2R W~jn"  
private String sFileName; //Saved File's Name ^SK!? M  
private int nSplitter; //Count of Splited Downloading File *c 9 S.  
/vC!__K9:  
}X. Fm'`  
public SiteInfoBean() %/ "yt}"|  
{//nSplitter的缺省值为5 xQl}~G]!  
//default value of nSplitter is 5 &G?"I%Vw  
this("","","",5); n6G&c4g<"  
} 2@IL  n+#  
%cBOi_}}~  
iNc!z A4  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) _mJhY0Oc  
{ 6s'n r7'0  
sSiteURL= sURL; YRMe<upo  
sFilePath = sPath; jib pZ)  
sFileName = sName; &xZSM,  
this.nSplitter = nSpiltter; )+ 'r-AF*  
7 IJn9b  
J *38GX+  
} \(--$9  
/pV N1Yt  
3D^cPkX  
public String getSSiteURL() qHT73_R  
{ }=Xlac_U  
return sSiteURL; gAVD-]`  
} !c dY`f6x  
K-@\";whF  
"$D'gS oYe  
public void setSSiteURL(String value) 'Lw8l `7  
{ mn\A)R Q  
sSiteURL = value; ZH*h1?\X  
} zl| XZ  
x6*y$D^B  
={f8s,m)P,  
public String getSFilePath() n_:EWm$\  
{ pe<T" [X  
return sFilePath; ]0BX5Z'  
} R.DUfU"gp  
\98N8p;,I  
><S(n#EB  
public void setSFilePath(String value) 8_ o~0lb  
{ |5ge4,}0  
sFilePath = value; 3rd8mh&l  
} W;l0GxOxQ  
qHtIjtt[q  
Z} t^i^u  
public String getSFileName() 0Lb{HLT  
{ luyu7`  
return sFileName; ,p /{!BX  
} k"C'8<T)'  
<1B+@  
p w5{=bD  
public void setSFileName(String value) cx ("F /Jm  
{ \q3ui}-9  
sFileName = value; *A4eYHn@  
} [S8*b^t4  
MT:VQ>f C  
 UO#`Ak  
public int getNSplitter() QleVW  
{ z@w}+fYO  
return nSplitter; JZ~wacDd  
} Jgg<u#  
l5~O}`gfh  
ml Cg&fnDB  
public void setNSplitter(int nCount) 1e7I2g  
{ ek U%^R<  
nSplitter = nCount; (9kR'kr  
} WUo\jm[yr  
} 1Lk(G9CoY  
ez.a  
;<thEWH;Y  
/* W amOg0  
**Utility.java )B)f`(SA"<  
*/ t1"#L_<e  
package NetFox; hvQXYo>TZx  
%4Qs|CM)m  
{qbe ye!  
public class Utility { :>r W`= e'  
uv<_.Jq]  
zx,9x*g  
public Utility() So8 Dwz?  
{ T:zM]%Xh  
iRlpNsN  
}ijQ*ECdl  
} IGT9}24  
SD{)Sq  
//线程睡眠 DW78SoyedZ  
public static void sleep(int nSecond) $evuL3GY#  
{ Kd5 8'$  
try{ `'sD(e  
Thread.sleep(nSecond); !lo /L  
} al-rgh  
catch(Exception e) "tl$JbRTY  
{ t*-c X  
e.printStackTrace (); x#N_h0[i  
} yjMN>L'  
} deVnAu =  
y+w,j]  
//日志 {j;` wN  
public static void log(String sMsg) |2@*?o"ll  
{ ; :q  
System.err.println(sMsg); m4m|?  
} 4OQ,|Wm4G  
h.F=Fhx/1  
k4hk* 0Jq  
public static void log(int sMsg) +xU({/  
{ A_9J ~3  
System.err.println(sMsg); ^3S&LC 1;|  
} V$w lOMp  
} =-X-${/  
 7gZ}Qy  
Mqvo j7  
/* f7][#EL  
**TestMethod.java R LMn&j|?e  
*/ e0(aRN{W  
package NetFox; Cl9nmyf   
..+#~3es#y  
Uc'}y!R  
public class TestMethod { )RvX}y-  
g#^MO]pY  
Iz#4!E|<  
public TestMethod() .(.<  
{ ///xx/weblogic60b2_win.exe !|i #g$  
try{ ;H.V-~:P)  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); {GLGDEb  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); YzQ1c~+  
SiteFileFetch fileFetch = new SiteFileFetch(bean); |\?u-O3  
fileFetch.start(); PnaiSt9p?r  
} kaB4[u  
catch(Exception e){e.printStackTrace ();} |rwY   
FE&:?  
F;8Q`$n  
} Q=fl!>P  
%dg[ho  
,xVAJ6_#  
public static void main(String[] args) (IVhj^dQm  
{ oD9n5/ozo  
new TestMethod(); _"L6mcI6  
} o0f`/ 6o  
} 2M'dT Xz  
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
如果您提交过一次失败了,可以用”恢复数据”来恢复帖子内容
认证码:
验证问题:
10+5=?,请输入中文答案:十五