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
  • 9194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
/* EEo+#  
**SiteFileFetch.java sIy$}_  
*/ l|up3A3)  
package NetFox; L+kS8D<  
import java.io.*; a0LX<}   
import java.net.*; "Q J-IRt &  
'+QgZ>q"  
#xo&#FIH  
public class SiteFileFetch extends Thread { /nmfp&@  
mn4;$1~e>H  
ut,"[+ J  
SiteInfoBean siteInfoBean = null; //文件信息Bean $7bmUQ|  
long[] nStartPos; //开始位置 CKR9APkv  
long[] nEndPos; //结束位置 JR>B<{xB  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 .z4FuG,R  
long nFileLength; //文件长度 !*ucVv;  
boolean bFirst = true; //是否第一次取文件 )I$Mh@F  
boolean bStop = false; //停止标志 O0l;Qi  
File tmpFile; //文件下载的临时信息 ixH7oWH#  
DataOutputStream output; //输出到文件的输出流 c]&VUWQ  
W2B=%`sC  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) pxC5a i  
public SiteFileFetch(SiteInfoBean bean) throws IOException f 0#V^[%Q  
{ ^R$dG[Qf  
siteInfoBean = bean; j,-7J*A~  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); k %rP*b*  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); e/3hb)#;  
if(tmpFile.exists ()) #3$|PM7,_  
{ 0`thND)?O  
bFirst = false; ;Dgp !*v=  
read_nPos(); #P@r[VZ{6  
} Dm^kuTIG  
else f:0n-me  
{ ;5l|-&{@*  
nStartPos = new long[bean.getNSplitter()]; [eN{Ft0x  
nEndPos = new long[bean.getNSplitter()]; 6qDD_:F  
} NNdS:(  
)gLasR.1  
Yt'o#"R)  
od fu7P_  
} NEH$&%OV?  
j%h Y0   
.0ZvCv:>  
public void run() CUG<v3\  
{ tSYnc7  
//获得文件长度  M:$nL  
//分割文件 }.vy|^X  
//实例FileSplitterFetch ?n+\T'f!  
//启动FileSplitterFetch线程 `ouzeu9}  
//等待子线程返回 LN^8U  
try{ &40]sxm  
if(bFirst) b#U%aPH  
{ /km3L7L%R  
nFileLength = getFileSize(); *X-$* ~J0  
if(nFileLength == -1) ;CZcY] ol  
{ BYf"l8^,  
System.err.println("File Length is not known!"); 7EXmmB~>,  
} /{va<CL  
else if(nFileLength == -2) /0uinx  
{ iD`XD\.?  
System.err.println("File is not access!"); mTgn}rXk  
} @ $R a  
else ;$Jvqq|T  
{ q}i87a;m  
for(int i=0;i<nStartPos.length;i++) y^rg%RV  
{ #*/h*GNMs  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); Z#O3s:`  
} hH/ O2  
for(int i=0;i<nEndPos.length-1;i++) g < o;\\  
{ VLN3x.BY  
nEndPos = nStartPos[i+1]; g-}sVvM  
} hzb|:  
nEndPos[nEndPos.length-1] = nFileLength; ~dLZ[6Z  
} nSiNSLv  
} ZM?r1Z4  
}"Cn kg  
{@%(0d{n}  
//启动子线程 >cb gL%  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; s`YuH <8  
for(int i=0;i<nStartPos.length;i++) F! e`i-xt  
{ TbVL71c  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), U'G`Q0n  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), QEKFuY<E+  
nStartPos,nEndPos,i); bl<7[J.  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); z;fSd  
fileSplitterFetch.start(); . 6dT5x8u  
} ^ym{DSx  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ^aCYh[=  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); gi>_>zStv  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", aO%FQ)BT  
nEndPos = " + nFileLength); V1`| j  
// fileSplitterFetch[nPos.length-1].start(); sQs5z~#51*  
zOdKB2_J7  
Zto E= 7K  
//等待子线程结束 du,-]fF  
//int count = 0; ^nF$<#a  
//是否结束while循环 jYz3(mM'J  
boolean breakWhile = false; dDbC0} x/  
eb\`)MI/  
<GRf%zJ  
while(!bStop) E;H(jVZ  
{ UD`Z;F  
write_nPos(); Kj 8 W  
Utility.sleep(500); f:5/y^M&  
breakWhile = true; *,*qv^  
Dt.Wb&V_w  
/ nFw  
for(int i=0;i<nStartPos.length;i++) X)OP316yx  
{ Qu_T&  
if(!fileSplitterFetch.bDownOver) hp4(f W  
{ %Qz`SO8x?  
breakWhile = false; ;%alZ  
break; DG?\6Zh  
} TWEqv<c  
} ;@ X   
if(breakWhile) J*X.0&Toc  
break; J9.p8A^^2  
 eb@Lh!  
z{L;)U B^  
//count++; zEfD{I  
//if(count>4) m0\}Cc  
// siteStop(); vP NZFi-(  
} K<JP9t6Qd  
|qDfFGYf  
QvN <uxm  
System.err.println("文件下载结束!"); L0  2~FT  
} 7=A9E]:  
catch(Exception e){e.printStackTrace ();} {Y%=/ba W  
} c[lob{,  
Ki6.'#%7  
NV4W2thYo  
//获得文件长度 >%dAqYi $  
public long getFileSize() i bs "Iv34  
{ no6]{qn=6  
int nFileLength = -1; F)kLlsp  
try{ <9tG_  
URL url = new URL(siteInfoBean.getSSiteURL()); vXQmEIm  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); H)aC'M^  
httpConnection.setRequestProperty("User-Agent","NetFox"); @zF:{=+]+  
u!k<sd_8B  
uN3J)@;_  
int responseCode=httpConnection.getResponseCode(); `1<3Hu_  
if(responseCode>=400) ,ri--<  
{ -L?% o_  
processErrorCode(responseCode); 8z8SwWS?  
return -2; //-2 represent access is error  .OS?^\  
} )}\@BtcjA]  
)ZyuF(C&  
VhIIW"1  
String sHeader; gD+t'qg$  
59BHGvaF  
c$:=d4t5$  
for(int i=1;;i++) Nw& }qSN  
{ (G%gVk]  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); s{J!^q  
//Utility.log(in.readLine()); WTv\HI2X !  
sHeader=httpConnection.getHeaderFieldKey(i); I jztj  
if(sHeader!=null) DLVs>?Y  
{ H6S vU  
if(sHeader.equals("Content-Length")) gs8@b5 RSb  
{ 9Sl|l.;!  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); XfK.Fj~-  
break; *Q120R  
} 8yz((?LrDh  
} &|"I0|tJ  
else '!h0![OH  
break; (DP9& b  
} MGyB8(  
} KXA)i5z  
catch(IOException e){e.printStackTrace ();} ::R00gd  
catch(Exception e){e.printStackTrace ();} [pFu ] ^X  
7oLf5V1~  
}\L !;6oy  
Utility.log(nFileLength); yxWMatZ2  
=,8Eo"~\  
b<V./rWIB  
return nFileLength; nEcd+7(  
} @&xaaqQ-  
Il`k]XM  
"mK i$FV  
//保存下载信息(文件指针位置) o``>sBZOq  
private void write_nPos() /A))"D  
{ rjQhU%zv  
try{ +ls*//R  
output = new DataOutputStream(new FileOutputStream(tmpFile)); AD%D ,l  
output.writeInt(nStartPos.length); Dzjt|U0ru9  
for(int i=0;i<nStartPos.length;i++) \j})Kul  
{ _u|FJTk  
// output.writeLong(nPos); {!eANm'  
output.writeLong(fileSplitterFetch.nStartPos); X<}o> 6|d  
output.writeLong(fileSplitterFetch.nEndPos); agU!D[M_G  
} :8-gm"awL5  
output.close(); KW7? : x  
} [gns8F#H\  
catch(IOException e){e.printStackTrace ();} Y0fO.k#C^  
catch(Exception e){e.printStackTrace ();} \pD=Lv9  
} QUZQY`' @  
l8AEEG8>  
ZIL| .<8I  
//读取保存的下载信息(文件指针位置) n$|c{2]=  
private void read_nPos() .0fh>kQ  
{ 9}jq`xSL  
try{ R~5* #r@f  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); SM#S/|.]  
int nCount = input.readInt(); CndgfOF  
nStartPos = new long[nCount]; 27 145  
nEndPos = new long[nCount]; O][Nl^dl  
for(int i=0;i<nStartPos.length;i++) i$^B-  
{ Q$h:[_v  
nStartPos = input.readLong(); "3i80R\w`F  
nEndPos = input.readLong(); _X2EBpZp  
} fxoi<!|iGY  
input.close(); Ag4Ga?&8ec  
} -6~y$c&c  
catch(IOException e){e.printStackTrace ();} Z'*Z@u3  
catch(Exception e){e.printStackTrace ();} 7kX$wQZ_  
} !MJe+.  
,Lun-aMd  
;y~{+{{Ow  
private void processErrorCode(int nErrorCode) "`i:)Et  
{ D@\;@( |  
System.err.println("Error Code : " + nErrorCode); g;!@DVF$  
} ?X#/1X%u:  
@6 ;oN  
r2GK_$vd  
//停止文件下载 r -q3+c^+  
public void siteStop() z'oiyXEE3  
{ l /png:  
bStop = true; MYhx'[4[3  
for(int i=0;i<nStartPos.length;i++) xBRh !w  
fileSplitterFetch.splitterStop(); {`H<=h__  
M9s43XL(&  
I' ! r  
} $~,}yh;  
} <{cNgKd9  
//负责部分文件的抓取 JYg% ~tW'  
**FileSplitterFetch.java 3 IWLBc  
*/ '-PMF~~S  
package NetFox; ?)' 2l6  
9XoQO9*Q  
^K.u ~p   
import java.io.*; phgexAq  
import java.net.*; 6vgBqn[  
8@ %mnyQ  
N=T.l*8  
public class FileSplitterFetch extends Thread { EY)Gi`lK  
hH1lgc  
EzIs@}  
String sURL; //File URL 2T@L{ql  
long nStartPos; //File Snippet Start Position 1O7]3&L@  
long nEndPos; //File Snippet End Position 0Ws;|Yg  
int nThreadID; //Thread's ID :/v,r=Y9p  
boolean bDownOver = false; //Downing is over cZgMA8 F  
boolean bStop = false; //Stop identical 1X::0;3  
FileAccessI fileAccessI = null; //File Access interface 7k] RO  
l 70,Jo?78  
i>Fvmw  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException P1i*u0a  
{ ^}o7*   
this.sURL = sURL; %-# q O  
this.nStartPos = nStart; ;Rhb@]X  
this.nEndPos = nEnd; dCZ\ S91q  
nThreadID = id; #`La|a.-  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 os1?6 z~  
} <8rgtu!VU  
G` ,u40a  
3$c(M99r  
public void run() ok`]:gf  
{ X%GD0h]X#  
while(nStartPos < nEndPos && !bStop) s !#HZK  
{ zb5N,!%r  
Xb]=:x(  
kG)2%  
try{ wqlcLIJPR  
URL url = new URL(sURL); IX<r5!  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ~^I\crx,U%  
httpConnection.setRequestProperty("User-Agent","NetFox"); jow7t\wk  
String sProperty = "bytes="+nStartPos+"-"; OGJ=VQA  
httpConnection.setRequestProperty("RANGE",sProperty); Y5ogi )  
Utility.log(sProperty); iW|s|1mh3  
ge0's+E+1  
E &7@#'l  
InputStream input = httpConnection.getInputStream();  c6Lif)4  
//logResponseHead(httpConnection); Q !9HA[Ly  
'lhP!E_)q  
M[aT2A  
byte[] b = new byte[1024]; 7L=T]W  
int nRead; @iU%`=ziz  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) .3VK;au\\  
{ )Fqy%uR8  
nStartPos += fileAccessI.write(b,0,nRead); r8uqcKfU  
//if(nThreadID == 1) PSTu/^  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); t`"^7YFS>  
} -@''[m.*  
=- $!:W~  
OlMBMUR:  
Utility.log("Thread " + nThreadID + " is over!"); CQdBf3q  
bDownOver = true; tTotPPZf}  
//nPos = fileAccessI.write (b,0,nRead); YP[LQ>  
} 'nRp}s1^[  
catch(Exception e){e.printStackTrace ();} NJ ZXs_%>$  
} n6b3E *  
} 6*ZU}xT  
[}>#YPZ  
1~%o}+#-  
//打印回应的头信息 ,e9CJ~a  
public void logResponseHead(HttpURLConnection con) u8Y~_)\MA  
{ '#v71,  
for(int i=1;;i++) m CM|&u  
{ [2Iau1<@  
String header=con.getHeaderFieldKey(i); tbq|,"  
if(header!=null) Ko#4z%Yq  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); z!fdx|PUX  
Utility.log(header+" : "+con.getHeaderField(header)); u(W^Nou/+  
else c~P)4(udT  
break; W_^>MLq  
} ajW[eyX  
} nV'3sUvR#  
-#Np7/  
I(pb-oY3!I  
public void splitterStop() ?>sQF4 V"  
{ Dk6?Nwy"  
bStop = true; EMLx?JnP  
} mA& =q_gS  
W. ^Ei\w/t  
p ZtgIS(3  
} lLH$`Wnv  
zK=dzoy  
l '/N3&5  
/* 3[VWTq)D=  
**FileAccess.java [*<.?9n)or  
*//文件访问(定位,写) (vKI1^,  
package NetFox; A8J8u,u9  
import java.io.*; $,TGP+vH  
:/B:FY=  
_R)&k%i}  
public class FileAccessI implements Serializable{ q0Xoj__c!A  
_z q)0\  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 c4\C[$  
RandomAccessFile oSavedFile; MU|{g 5/ )  
long nPos; Ls]@icH0  
r*chL&7  
i^WIr h3a  
public FileAccessI() throws IOException lzEb5mg  
{ W6vf=I@f  
this("",0); lWbZ=x_0  
} G]4OFz+  
,+se  
\^LWCp,C"  
public FileAccessI(String sName,long nPos) throws IOException r@iASITX  
{ u)v$JpNE  
oSavedFile = new RandomAccessFile(sName,"rw"); &pM'$}T*  
this.nPos = nPos; [B,'=,Hbs  
oSavedFile.seek(nPos); %swR:Bv  
} <s_=-" il  
?4 qkDtm  
H'EY)s Hi  
public synchronized int write(byte[] b,int nStart,int nLen) ZRnL_ z~  
{ pYt/378w  
int n = -1; QQFf5^  
try{ SG:bM7*1'  
oSavedFile.write(b,nStart,nLen); M ?*Tf&  
n = nLen; 34ha26\np  
} vI Vr@1S  
catch(IOException e) 9x? B5Ap[  
{ }p=g*Zo*C;  
e.printStackTrace (); MAnp{  
} Q[uAIyv0  
77*qkKr  
cx{T '1  
return n; D{cZxI  
} r,4lqar;E  
OEnDsIhq  
W5.Va.  
} L]I3P|y_  
cD2+hp|9  
&Yf",KcL*I  
/* \, 8p1$G  
**SiteInfoBean.java 'a#mViPTQ)  
*/ f"Vgefk  
package NetFox; D L{R|3{N  
 / +1{  
P]Xbjs<p  
public class SiteInfoBean { $"\O;dp7l  
1 {Jb"  
 F~6#LT  
private String sSiteURL; //Site's URL ^ S  
private String sFilePath; //Saved File's Path X\\7$  
private String sFileName; //Saved File's Name Q`A6(y/s?  
private int nSplitter; //Count of Splited Downloading File @*(4dt:V  
OP%?dh]  
T6Ctf#  
public SiteInfoBean() OR4!YVVQ  
{//nSplitter的缺省值为5 j)by}}  
//default value of nSplitter is 5 J R$r!hX  
this("","","",5); %ucjMa>t  
} EB!daZH,  
(?3[3 w~  
SdJ/ 4&{ !  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) X3wX`V}  
{ 'e@=^FC  
sSiteURL= sURL; _dU8'H  
sFilePath = sPath; x6;j<m5Mjx  
sFileName = sName; g?G+dnl/8  
this.nSplitter = nSpiltter; J#Z5^)$  
u1Ek y/e-  
\4{2eU  
} KKEN'-3  
nX^1$')gp  
l?8)6z#Zl  
public String getSSiteURL()  f:wd&V  
{ c0ez/q1S  
return sSiteURL; bA@P}M)X  
} e;VIL 2|  
Kesy2mE  
s+Q;pRZW{  
public void setSSiteURL(String value) aDL*W@1S  
{ *hdC?m. _  
sSiteURL = value; C4\,z\Q  
} F[Q!d6  
(qBvoLkF9N  
ys'T~Cs  
public String getSFilePath() @hif$  
{ LA%bq_> f  
return sFilePath; VK:8 Nk_y  
} AIRr{Y  
1J}8sG2`  
y(a!YicA?  
public void setSFilePath(String value) eV7 u*d?  
{ ;%!B[+ut"  
sFilePath = value; DCQ^fZ/  
} *5V Xyt2  
%gd(wzco  
mC[UXN/  
public String getSFileName() -*a?<ES`  
{ MCc$TttaVz  
return sFileName; @5VV|Wt=  
} "D][e'  
6!q#x[A  
^qvZ XS  
public void setSFileName(String value) Uxu\u0*  
{ E9}{1A  
sFileName = value; 8VQ 24r  
} x\\~SGd  
jS<_ )  
tPfFqqT  
public int getNSplitter() ]zfG~^.  
{ #VVr"*7$  
return nSplitter; Vj?DA5W`'  
} +&|S'7&{  
Sr_VL:Gg  
 dy>!KO  
public void setNSplitter(int nCount) bh p5<N  
{ 'h1b1,b~  
nSplitter = nCount; T=Z.TG|lIx  
} XfYC7-e9c  
} j&R+2%  
ArK]0$T   
Te,$M3|  
/* 9 QC.TG@  
**Utility.java -&2B@]]  
*/ 'gso'&Uaj  
package NetFox; uz3 0_aH  
sEc;!L  
%^]?5a!  
public class Utility { As&v Ft P  
++-{]wB3=.  
w ej[+y-  
public Utility() %A/_5;PZ/  
{ 1|r,dE2k9  
fbvbz3N  
@Xp~2@I=ls  
} tBATZ0nK`Q  
Gi2$B76<  
//线程睡眠 zDTv\3rZ4X  
public static void sleep(int nSecond) xdvh-%A4  
{ 3< Od0J  
try{ :4gLjzL  
Thread.sleep(nSecond); bM,1f/^  
} M~Ttb29{  
catch(Exception e) Cq)IayD@  
{ Ro(Zmk\t  
e.printStackTrace (); jE2}p-2Q0  
} kgdT7  
} R(Kk{c:-@  
^' M>r (t  
//日志 q`NXJf=sc  
public static void log(String sMsg) {'En\e  
{ Q]/Uq~m C  
System.err.println(sMsg); aGZi9O7G}  
} nC1zzFFJ  
Y?J"wdWJNB  
/4\wn?f  
public static void log(int sMsg) 7R4z}2F2  
{ mEyK1h1G @  
System.err.println(sMsg); K14^JAdY/  
} M=qb^~ l  
} 1 rs&74-  
DV)3  
pCh2SQ(Q>  
/* -s|8<A||"  
**TestMethod.java J (4"S o_  
*/ d?AlI  
package NetFox; Sq\(pfv o  
NEt1[2X%  
2 dp>Z",  
public class TestMethod { wr(*?p]R  
=Z=o#46JY  
a, Q#Dk  
public TestMethod() ZK;zm  
{ ///xx/weblogic60b2_win.exe jHXwOJq %  
try{ 'y]\-T  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ~S,p?I  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); za Tb~#c_  
SiteFileFetch fileFetch = new SiteFileFetch(bean); @yd4$Mv8%  
fileFetch.start(); ]?O2:X  
} @Jm7^;9/  
catch(Exception e){e.printStackTrace ();} )a@k]#)Skm  
5tjP6Z`!9`  
W&(k!6<x  
} Yim<>. !  
>_OYhgs1w  
css64WX^0c  
public static void main(String[] args) 3 >E%e!D%  
{ &k-Vcrcz  
new TestMethod(); W[EKD 7  
} 9O{b]=>wq  
} l3Njq^T  
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:
3+5=?,请输入中文答案:八 正确答案:八