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
  • 12003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
/* C=(~[Y  
**SiteFileFetch.java 't+'rG6x  
*/ j+[oZfH  
package NetFox; |}Mthj9n  
import java.io.*; T[kS;-x  
import java.net.*; &"DD&87N%  
{Zo*FZcaX  
B/dJj#  
public class SiteFileFetch extends Thread { 9qm'qx  
pER[^LH_)  
MUUhg  
SiteInfoBean siteInfoBean = null; //文件信息Bean ?N]G;%3/  
long[] nStartPos; //开始位置 W/.Wp|C}K3  
long[] nEndPos; //结束位置 =yZ6$ hK  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 y=zs6HaS  
long nFileLength; //文件长度 "qoJIwl#q  
boolean bFirst = true; //是否第一次取文件 IwR=@Ne8  
boolean bStop = false; //停止标志 B$MHn?  
File tmpFile; //文件下载的临时信息 UaBNoD  
DataOutputStream output; //输出到文件的输出流 z`sW5K(A  
f('##pND@  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) BO0Y#fs  
public SiteFileFetch(SiteInfoBean bean) throws IOException ~^>g<YR[  
{ (dP9`Na]  
siteInfoBean = bean; 2XyC;RWJ%  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); kH?PEA! \  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); Y mm*p,`  
if(tmpFile.exists ()) _ygdv\^Tet  
{ !'Ww%ZL\   
bFirst = false; .J?RaH{i  
read_nPos(); ik5"9b-\<  
} I5E+=.T*ar  
else et<@3wyd]  
{ :=\`P  
nStartPos = new long[bean.getNSplitter()]; d?><+!a  
nEndPos = new long[bean.getNSplitter()]; |nY+Nen7  
} ~?B\+6<V  
#J~xKyJi'  
$]MOAj"LH  
U04)XfO;]  
} !, {-q)'D  
vj"['6Xa  
KN~Repcz@  
public void run() dTqL[?wH?  
{ xP &@|Ag  
//获得文件长度 O^IS:\JX&  
//分割文件 3 <Zo{;  
//实例FileSplitterFetch -Fc 9mv(H  
//启动FileSplitterFetch线程 kfq<M7y  
//等待子线程返回 o3HS|  
try{ syk,e4:oA  
if(bFirst) JqtOoR  
{ 4F+G;'JV  
nFileLength = getFileSize(); ~R7{gCqdr  
if(nFileLength == -1) $E^*^({  
{ FYH^axpp  
System.err.println("File Length is not known!"); Ni#y=cb  
} v1$ }JX   
else if(nFileLength == -2) :<uCi\9(  
{ d.k'\1o  
System.err.println("File is not access!"); j6Au<P  
}  /UtSZ(  
else ).jna`A,  
{ qot {#tk d  
for(int i=0;i<nStartPos.length;i++) w[J.?v&^  
{ :AyZe7:(D  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); <Ys7`e6eY  
} cq9d;~q  
for(int i=0;i<nEndPos.length-1;i++) :fQN_*B4@4  
{ Fl++rUT  
nEndPos = nStartPos[i+1]; p<&dy^mS  
} N|w;wF!3  
nEndPos[nEndPos.length-1] = nFileLength; soqnr" 1  
} wD SSgk  
} Mm%b8#Fe!  
xI8v'[3  
e*o:ltP./  
//启动子线程 F8B:P7I  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; 8},fu3Z  
for(int i=0;i<nStartPos.length;i++) JB HnJm  
{ mWuhXY^Q  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), D1EHT}  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), t}gK)"g  
nStartPos,nEndPos,i); Co`:D  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); kv`5"pa7M  
fileSplitterFetch.start(); +'UxO'v3]  
} t_Ul;HVPS  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), +Q!Kj7EU/  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); (ewcj\l4*  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", IXsOTBM  
nEndPos = " + nFileLength); "~T06!F45  
// fileSplitterFetch[nPos.length-1].start(); a2H_8iQ!  
Q]-r'pYr  
)==Qo/N:  
//等待子线程结束 K555z+,'e  
//int count = 0; ; .hTfxE0  
//是否结束while循环 5S4`.'  
boolean breakWhile = false; >|JMvbje  
sE0,b  
7` t,   
while(!bStop) ? \NT'CG  
{ E9j(%kQ2  
write_nPos(); eb<' >a  
Utility.sleep(500); g= s2t"&  
breakWhile = true; X($@E!|  
,@t#)HV  
(ce"ED`1  
for(int i=0;i<nStartPos.length;i++) v9Ez0 :)  
{ 0*o=JM]  
if(!fileSplitterFetch.bDownOver) 'Y5=A!*@tf  
{ 62#8c~ dL  
breakWhile = false; Cv qUaHW@  
break; ;sd] IZ$#  
} YHr<`Q</  
} 5fK<DkB$>:  
if(breakWhile) vo2TP:  
break; Dz+R Q`Vn  
<(Ktf0'__  
V,:~FufM^  
//count++; ]j< & :_  
//if(count>4) m ,TYF  
// siteStop(); ooT~R2u  
} 5v#_2Ih  
{4b8s%:!4  
<nn!9V\C   
System.err.println("文件下载结束!"); SMh[7lU`  
} JP 8v2) p  
catch(Exception e){e.printStackTrace ();} mC84fss  
} 1iE*-K%Q  
k!m9 l1x  
K|-RAjE  
//获得文件长度 vC5y]1QDd  
public long getFileSize() eh$T 3_#q  
{ q.PXO3T  
int nFileLength = -1; L!kbDbqn  
try{ Ib$?[  
URL url = new URL(siteInfoBean.getSSiteURL()); ;EfREfk  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); xsXf_gGu  
httpConnection.setRequestProperty("User-Agent","NetFox"); )"<:Md$7  
p\M\mK  
{NV=k%MTmi  
int responseCode=httpConnection.getResponseCode(); -Tr*G4  
if(responseCode>=400) Q?W}]RW  
{ 1FmVx   
processErrorCode(responseCode); cGe-|>:  
return -2; //-2 represent access is error JU0|pstf  
} ^ZO3:"t!w  
`Yc>I!iN  
X !l#1  
String sHeader; -j"2rIl4#  
5}2XnM2  
aD8r:S\  
for(int i=1;;i++) [7SR2^uf<j  
{ =%oKYQ  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); j0[9Cj^%c  
//Utility.log(in.readLine()); RDQK_Ef:  
sHeader=httpConnection.getHeaderFieldKey(i); A+F@JpV  
if(sHeader!=null) 8Wyv!tL  
{ I;Bcim;  
if(sHeader.equals("Content-Length")) OAtn.LU  
{ Tta+qjr  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); @60/IE{-v  
break; -m>ng E~q  
} qW:\6aEG  
} x$aFJ CL  
else /|{~GD +A&  
break; 9`sIE_%+  
} .(2ui~ed  
} $qj||zA  
catch(IOException e){e.printStackTrace ();} Md,KW#  
catch(Exception e){e.printStackTrace ();} o9uir"=  
 (.B+U'6  
Ndr4e?Xa,  
Utility.log(nFileLength); {H%1sI  
;]Bkw6 o  
ZtqN8$[6n  
return nFileLength; N b@zn0A(;  
} %QrpFE5 V5  
>R}p*=J  
9q !./)  
//保存下载信息(文件指针位置) xBi``x2eY  
private void write_nPos() ]QAMCu(>  
{ 9 ~$' ?  
try{ Gfn?1Kt{  
output = new DataOutputStream(new FileOutputStream(tmpFile)); )s4a<S c]  
output.writeInt(nStartPos.length); itW~2#nJz  
for(int i=0;i<nStartPos.length;i++) seo.1.Da2  
{ }~`l!ApD  
// output.writeLong(nPos); j -j,0!T~b  
output.writeLong(fileSplitterFetch.nStartPos); )YP 9  
output.writeLong(fileSplitterFetch.nEndPos); Yn }Ivg  
} " tUF,G(<  
output.close(); IF$*6 ,v.z  
} &%4*~;o  
catch(IOException e){e.printStackTrace ();} *(sFr E  
catch(Exception e){e.printStackTrace ();} w*"h#^1z  
} E<XrXxS1O  
g}=opw6z  
<rpXhcR  
//读取保存的下载信息(文件指针位置)  @Iy&Qo  
private void read_nPos() )~l`%+  
{ @-QDp`QtI  
try{ ,a /<t"  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); Cn>RUGoUsI  
int nCount = input.readInt(); D#G(&<Q  
nStartPos = new long[nCount]; Lcpz(W ^  
nEndPos = new long[nCount]; Y^@Nvt$<K  
for(int i=0;i<nStartPos.length;i++) 1WW`%  
{ R s)Nz< d  
nStartPos = input.readLong(); dLn Md0  
nEndPos = input.readLong(); =Wj{J.7mf]  
} O}IRM|r"  
input.close(); x<%V&<z1g  
} Lk~aM bw#  
catch(IOException e){e.printStackTrace ();} }\Mmp+<  
catch(Exception e){e.printStackTrace ();} >'X[*:Cx  
} 60 z =bd]  
o|BEY3|  
To"J>:l  
private void processErrorCode(int nErrorCode) ir ^XZVR  
{ wNgS0{}&`  
System.err.println("Error Code : " + nErrorCode); a yQB@2%  
} ;K9rE3  
oH|<(8efD  
zn@yt%PCV  
//停止文件下载 + (|6Wv  
public void siteStop() JxM[LvVi  
{ cc^[ u+  
bStop = true; $m-rn'Q  
for(int i=0;i<nStartPos.length;i++) h!L6NS_Q,  
fileSplitterFetch.splitterStop(); zU)Ib<$  
4D-4BxN*  
H_CX5=Nq^  
} nmZJ%n  
} y`OL^D4  
//负责部分文件的抓取 06#40-   
**FileSplitterFetch.java  )6 _+  
*/ 4/tp-dBip  
package NetFox; PV_q=70%T  
w_hGWpm  
7FiQTS B:  
import java.io.*; xiW;Y{kZ  
import java.net.*; s;;"^5B.  
T$ )dc^  
JBKCa 3  
public class FileSplitterFetch extends Thread { ZRd,V~iz  
ZOK,P  
Dqw?3 KB  
String sURL; //File URL S EeDq/h  
long nStartPos; //File Snippet Start Position eQRY xx{  
long nEndPos; //File Snippet End Position Mh+ym]6\(k  
int nThreadID; //Thread's ID kr|u ||  
boolean bDownOver = false; //Downing is over >$yqx1=jW  
boolean bStop = false; //Stop identical DVWqrK}q  
FileAccessI fileAccessI = null; //File Access interface CI )89`  
k7gm)}RKcu  
DJmT]Q]o)  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException <+oTYPgD9  
{ 9a*}&fL[  
this.sURL = sURL; @N-P[.qL"  
this.nStartPos = nStart; J~jR`2+r  
this.nEndPos = nEnd; %fyah}=  
nThreadID = id; /bd1Bi  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 LPNJuz  
} u#l@:p  
8sG0HI$f+  
rI E m  
public void run() :6*FnKD  
{ ;m+*R/  
while(nStartPos < nEndPos && !bStop) 0;kp`hB  
{ $# /-+>  
|9F^"7Q~C  
2C!Ko"1Y'  
try{ )lo;y~ o  
URL url = new URL(sURL); 2V 1|b`b#4  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); BSGC.>$s  
httpConnection.setRequestProperty("User-Agent","NetFox"); yR Zb_Mq9U  
String sProperty = "bytes="+nStartPos+"-"; VNmQ'EuV}2  
httpConnection.setRequestProperty("RANGE",sProperty); 5IPZ;  
Utility.log(sProperty); !Cpy )D(  
x@ZxV*T^  
O7_u9lz2  
InputStream input = httpConnection.getInputStream(); R4V~+tnbG&  
//logResponseHead(httpConnection); v?U;o&L(  
xSQ:#o=8G  
i'$V'x'k  
byte[] b = new byte[1024]; {v,O  
int nRead; ue5C ]  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) E26zw9d  
{ Sl8A=Ez  
nStartPos += fileAccessI.write(b,0,nRead); P)2.Gx/  
//if(nThreadID == 1) NRM=0-16u$  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); VoOh$&"M  
} \!erP!$x .  
KL8G2"Z  
2k}" 52  
Utility.log("Thread " + nThreadID + " is over!"); P@m_tA%  
bDownOver = true; )e$}sw{t  
//nPos = fileAccessI.write (b,0,nRead); |(Bc0sgw}  
} 3Vu_-.ID  
catch(Exception e){e.printStackTrace ();} $fhb-c3  
} r{V=)h  
} %V+hm5Q  
0.9%m7.m  
f8T6(cA  
//打印回应的头信息 Eu4-=2!4  
public void logResponseHead(HttpURLConnection con) =peodj^  
{ fr\"MP  
for(int i=1;;i++) H}R/_5g  
{ fq@r6\TI  
String header=con.getHeaderFieldKey(i); zJH#J=O  
if(header!=null) B~[QmK  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ]Cfjs33H  
Utility.log(header+" : "+con.getHeaderField(header)); O M]d}}=Y  
else s7A3CY]->  
break; 4pin\ZS:C  
} 29xm66  
} x.+r.cAXH  
tJ{3Z}K  
']N1OVw^vf  
public void splitterStop() -A?6)ggf.  
{ xp!M A  
bStop = true; 56;^ NE4  
} /Ria"lLv  
% Rv ;e  
e;M#MkP7  
} 8QYP\7}o  
jf`QoK  
)(?,1>k`Z  
/* + [JvpDv%  
**FileAccess.java ^/0c`JG!x  
*//文件访问(定位,写) AG3iKk??T  
package NetFox; m#\I&(l+  
import java.io.*; [9wuaw"~[Z  
lo1<t<w`  
D#=$? {w  
public class FileAccessI implements Serializable{ }#u.Of`6"  
 b6`_;Z  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 =RA8^wI  
RandomAccessFile oSavedFile; D%=VhKq  
long nPos; H2ZRUFu  
;qA(!`h+  
~o_zV'^f@o  
public FileAccessI() throws IOException ?5N7,|K)  
{ pk%%}tP<  
this("",0); eHQS\n  
} q X"Pg  
qhdY<[6  
DRDn;j  
public FileAccessI(String sName,long nPos) throws IOException 6.!aJJLN  
{ V0rS^SAF  
oSavedFile = new RandomAccessFile(sName,"rw"); { ]*#WU  
this.nPos = nPos; :i?7RouO  
oSavedFile.seek(nPos); x1@`\r#0  
} 4Bn <L&@/  
}f l4^F  
S%^*h{9u"  
public synchronized int write(byte[] b,int nStart,int nLen) %kHeU=  
{ 0eGz|J*7  
int n = -1; $ $=N'Q  
try{ c:J;Q){Xz  
oSavedFile.write(b,nStart,nLen); ii3{HJ*C  
n = nLen; \ah.@s  
} A~@u#]]<n  
catch(IOException e) {Rm N1'%  
{ W~!uSrY  
e.printStackTrace (); lYF~CNvE  
} m@Q%)sc)  
c%jW'  
CeZ+!-lG  
return n; S'h{["P~ 0  
} q':P9 o*N?  
=tKb7:KU  
(GeOD V?U  
} ^$!H|  
P^)J^{r  
Z\\'0yuY(  
/* ^Fn~@'  
**SiteInfoBean.java B24,;2J  
*/ _^k9!V jo  
package NetFox; @@ 1Sxv_  
`|rr<Tsy\  
[U^@Bkh  
public class SiteInfoBean { R5,ISD +s  
kKFhbHUZa  
(}4]U=/nV  
private String sSiteURL; //Site's URL h1(GzL%i_  
private String sFilePath; //Saved File's Path +o4W8f=Ga  
private String sFileName; //Saved File's Name fz[-pJ5[  
private int nSplitter; //Count of Splited Downloading File _Nx#)(x  
o^\L41x3  
C$<['D?8  
public SiteInfoBean() 1MPn{#Ff  
{//nSplitter的缺省值为5 J"$Y`;  
//default value of nSplitter is 5 x1O]@Z{d\  
this("","","",5); M[= #%U3*N  
} !eC]=PoY  
O>M4%p  
# ~I.F4  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 'QP~uK  
{ q83!PI  
sSiteURL= sURL; !&f>,?wlP  
sFilePath = sPath; (2l?~CaK  
sFileName = sName; @hG]Gs[,o  
this.nSplitter = nSpiltter; OsGKlWM/  
dfa^5`_  
sN8)p%'Lg  
} vJ a?5Jr  
*#| lhf'  
VGVb3@  
public String getSSiteURL() ImG7E w  
{ jgyXb5GY  
return sSiteURL; skeXsls  
} H!81Pq~  
rHMr8,J;  
c+bOp 05o-  
public void setSSiteURL(String value) 6a%dq"5 +  
{ FRR`<do5$,  
sSiteURL = value;  9EU0R H  
} s6YnNJ,SK  
ukAE7O(W&  
:W6R]y  
public String getSFilePath() 7xlarns   
{ v6#i>n~x,  
return sFilePath; qJyGr ?  
} }TDoQ]P  
C}D\^(nLu.  
VmbfwHRWb  
public void setSFilePath(String value) b;~?a#Z}  
{ +p\+ 15  
sFilePath = value; #$?!P1  
} @krh<T6|  
U'Mxf'q  
=*\(Y (0  
public String getSFileName() xfFsW^w  
{ z"PU`v  
return sFileName; Vgg' 5o&.  
} C U 8s*  
: 6|nXL  
j +u3VP  
public void setSFileName(String value) i9O;D*  
{ 7&>==|gt  
sFileName = value; vk K8D#K  
} *`WD/fG  
'#ow 9w+^  
-n#fj;.2_  
public int getNSplitter() P6 ~& ,a  
{ 5W4Tp% Lda  
return nSplitter; )"sJaHx<  
} v9K=\ j  
/@xL {  
-q")qNt.  
public void setNSplitter(int nCount) 1!"iN~  
{ _2 Hehw  
nSplitter = nCount; YX,xC-37y  
} mzH3Q564  
} &3~_9+  
A` )A=L  
eZ`x[g%1  
/* tFrNnbmlQ  
**Utility.java \O G`+"|L  
*/ _WB*ArR  
package NetFox; CWx_9b zk  
dxk~  
1_MaaA;ow"  
public class Utility { DMpNm F>  
FXO{i:Zo  
kgGMA 7Jy  
public Utility() wNtPh&  
{ "}ZUa~7  
&l;wb.%ijW  
_2p D  
} K!A;C#b!  
skzTw66W.  
//线程睡眠 M?I^Od'8  
public static void sleep(int nSecond) 96 P3B}Dk  
{ ~z&Ho  
try{ 9{Xh wi)z  
Thread.sleep(nSecond); |*te69RX  
} 5 cz6\A&  
catch(Exception e)  97-=Vb  
{ 3uJ>:,~r  
e.printStackTrace (); =c Krp'  
} T.B} k`$  
} *R8qnvE\()  
M7. fz"M  
//日志 DFN  
public static void log(String sMsg) EhK~S(r^  
{  FtmI\,  
System.err.println(sMsg); H;kk:s'  
} @(I)]Ca%O  
snti*e4"V  
Rf0F`D k  
public static void log(int sMsg) yIG*  
{ 0OF]|hH  
System.err.println(sMsg); O od?ifA  
} l~j{i/>  
} GkYD:o=qx  
`bMwt?[*  
Q ~>="Yiu  
/* QbG`F8dj  
**TestMethod.java b _%W*Q  
*/ C=!YcJ9  
package NetFox; p({)ZU3  
n.tJ-l5[  
O$$$1VHYo  
public class TestMethod { NUb:5tL  
+8eW/Bs@2  
+E8}5pDt  
public TestMethod() e_z"<yq  
{ ///xx/weblogic60b2_win.exe ns;nle|m  
try{ IP-}J$$1  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); jSMs<ox  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); [X=J]e^D  
SiteFileFetch fileFetch = new SiteFileFetch(bean); @ 9q/jv`  
fileFetch.start(); ^iz2 =}Q8  
} w/Ej>OS  
catch(Exception e){e.printStackTrace ();} avwhGys#  
;y%C\YB#  
HS[N]'dc  
} gW_^GrKpI  
uU#7SX(uu  
oNa*|CSE>  
public static void main(String[] args) & GM&,  
{ vddh 2G  
new TestMethod(); 8j%hxAV$  
} "F8A:tR  
} 8"2X 8C8  
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
欢迎提供真实交流,考虑发帖者的感受
认证码:
验证问题:
10+5=?,请输入中文答案:十五