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
  • 11434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
/* >lA7*nn  
**SiteFileFetch.java Qe2m8  
*/ tegOT]|  
package NetFox; c*.G]nRc  
import java.io.*; D",A$(lG  
import java.net.*; 5>'?:jY  
fkW3~b  
nURvy}<r  
public class SiteFileFetch extends Thread { y!S^xS  
VKT@2HjNT`  
#t=[w  
SiteInfoBean siteInfoBean = null; //文件信息Bean I") H~  
long[] nStartPos; //开始位置 "(0oP9lZ  
long[] nEndPos; //结束位置 ])N|[|$  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 sk#9x`Rw  
long nFileLength; //文件长度 jz %;4e~t  
boolean bFirst = true; //是否第一次取文件 p9/bzT34.  
boolean bStop = false; //停止标志 BD hLz  
File tmpFile; //文件下载的临时信息 p:Iw%eZ:  
DataOutputStream output; //输出到文件的输出流 Bp &6x;MJf  
f8^"E $"  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) (})]H:W7  
public SiteFileFetch(SiteInfoBean bean) throws IOException dj3|f{kg{  
{ &K06}[J  
siteInfoBean = bean; kX igX-  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); b+W)2rFO  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); XlRw Z/Wc  
if(tmpFile.exists ()) W7%p^;ZQ$  
{ HpW" lYW4  
bFirst = false; T48BRVX-F  
read_nPos(); F\;2 i:(  
} ]AFj&CteZ/  
else !K!)S^^Po?  
{ -_s%8l^  
nStartPos = new long[bean.getNSplitter()]; DD2adu^  
nEndPos = new long[bean.getNSplitter()]; )i&%cyZw  
} !{ $qMhT  
mRwXN*Izw  
:}^Rs9 '  
GNs#oM  
} dI!8S  
w"q-#,37j  
ot^q}fRX  
public void run() 6@&fvf  
{ 6e*%\2UA  
//获得文件长度 aZP 2R"  
//分割文件 z|uOJ0uK  
//实例FileSplitterFetch ]n~yp5Nbr  
//启动FileSplitterFetch线程 {!lNL[x  
//等待子线程返回 P_Z M'[  
try{ 2>g^4(  
if(bFirst) ]Fxku<z7|  
{ HHZ`%  
nFileLength = getFileSize(); B i'd5B5  
if(nFileLength == -1) {&E?<D2_&  
{ wc"9A~  
System.err.println("File Length is not known!"); u',b1 3g(  
} 5;}2[3}[  
else if(nFileLength == -2) WmNA5;<Q  
{ PVhik@Yoh  
System.err.println("File is not access!"); @]*[c})/  
} nZ~kZ |VS  
else </,.K`''W  
{ cxgE\4_u"  
for(int i=0;i<nStartPos.length;i++) $Tfm/=e  
{ >Dxe>Q'df  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); 18jJzYawh  
} S,XKW(5   
for(int i=0;i<nEndPos.length-1;i++) YDW|-HIF  
{ jg?bf/$s  
nEndPos = nStartPos[i+1];  %W(^6p!  
} k<!<<,Z  
nEndPos[nEndPos.length-1] = nFileLength; (9E( Q*J5x  
} / HL_$g<  
} \/n+j!  
Z A[)  
00"CC  
//启动子线程 /\d(c/,4  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; V- /YNRV  
for(int i=0;i<nStartPos.length;i++) AH|Y<\  
{ '|_/lz$h  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), MBlBMUJk  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 5lGQ#r  
nStartPos,nEndPos,i); 7"#f!.E  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); d)\2U{  
fileSplitterFetch.start(); |88CBiu}  
} uj)yk*  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ubi~%  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 5 5^tfu   
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", W8y$ Ve8m  
nEndPos = " + nFileLength); r|<6Aae&  
// fileSplitterFetch[nPos.length-1].start(); r5[4h'f  
6s5yyy=L%~  
Nfg{,/ O  
//等待子线程结束 c+~Lp SQ  
//int count = 0; =x1Wii$`  
//是否结束while循环 #,TELzUVE  
boolean breakWhile = false; -;vT<G3  
N\'TR6_,b  
Yc|uD-y  
while(!bStop) X{`1:c'x  
{ Oo1ecbY  
write_nPos(); (#If1[L  
Utility.sleep(500); ~}K{e  
breakWhile = true; 5?w.rcN[j  
RtwUb(wn6  
|U EC  
for(int i=0;i<nStartPos.length;i++) "-P/jk  
{ <1K7@Tu  
if(!fileSplitterFetch.bDownOver) 3-iD.IAUm@  
{ IytDvz*|  
breakWhile = false; XC2FF&B&  
break; ,m:L2 -J@  
} Ch t%uzb,  
} Cs#w72N  
if(breakWhile) JYQ.EAsr!  
break; "H$@b`)  
\ADLMj`F|  
L:pUvcAc?  
//count++; O>%$q8x@i  
//if(count>4) m<3w^mww  
// siteStop(); tvGlp)?.  
} []gRfM]$&  
sBU_Ft  
N}DL(-SQ3  
System.err.println("文件下载结束!"); JCD?qeTg  
} or!!s 5[d  
catch(Exception e){e.printStackTrace ();} !9D1 Fa  
} y6FKg)  
)b9_C O}  
r8,om^N6  
//获得文件长度 @D]lgq[  
public long getFileSize() yPN+W8}f  
{ C `6S}f,  
int nFileLength = -1; Mb.4J2F?  
try{ Im+ 7<3Z  
URL url = new URL(siteInfoBean.getSSiteURL()); !b63ik15O~  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); WL1\y|  
httpConnection.setRequestProperty("User-Agent","NetFox"); $ser+Jt=  
!W /C[$E  
*QE"K2\5  
int responseCode=httpConnection.getResponseCode(); tDt :^Bc  
if(responseCode>=400) <h@]Ri  
{ ^Q\XGl  
processErrorCode(responseCode); qe%V#c  
return -2; //-2 represent access is error CdL.?^  
} ot }6D  
#q;z8 @  
|z*>ixK  
String sHeader; #x)8f3I  
(hN?:q?'  
zSXA=   
for(int i=1;;i++) Ha)np  
{ $w/E9EJ)3A  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); mX;H((  
//Utility.log(in.readLine()); B`1kGEx .  
sHeader=httpConnection.getHeaderFieldKey(i); |vz9Hs$@l  
if(sHeader!=null) j^nu|  
{ \c% g M1  
if(sHeader.equals("Content-Length")) `[Sl1saZ$S  
{ $@.jZ_G  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); e2wvc/gG6  
break; F&az":  
} h/?6=D{  
} SY T$3|a  
else ;MPKJS68@  
break; 9go))&`PJL  
} oj@g2H5P  
} E-SG8U;  
catch(IOException e){e.printStackTrace ();} `tVy_/3(9  
catch(Exception e){e.printStackTrace ();} :c:V%0Yji  
.&|L|q}  
(NaK3_  
Utility.log(nFileLength); "V}qf3 qU  
I_>`hTiR  
v2>Z^  
return nFileLength; M1{(OY(G  
} s[X B#)H4  
CA*~2|  
#xp(B5  
//保存下载信息(文件指针位置) m9t$h  
private void write_nPos() U&W"Ea=R/  
{ `0@z"D5c  
try{ YPEnNt+  
output = new DataOutputStream(new FileOutputStream(tmpFile)); Y.-S=Y   
output.writeInt(nStartPos.length); T5e^J"   
for(int i=0;i<nStartPos.length;i++) W;TJenv  
{ H,K`6HH  
// output.writeLong(nPos); ?1w"IjUS  
output.writeLong(fileSplitterFetch.nStartPos); B;W(iI  
output.writeLong(fileSplitterFetch.nEndPos); X8R1a?  
} pkk4h2Ah  
output.close(); GTAf   
} (a#pvEY  
catch(IOException e){e.printStackTrace ();} 0Oap39  
catch(Exception e){e.printStackTrace ();} Y;_T=  L  
} -Qb0:]sV#  
J\A8qh8  
/b%Q[ Ck_  
//读取保存的下载信息(文件指针位置) I`^YAbnb  
private void read_nPos() X"<|Z]w  
{ @GeHWv  
try{ :1_mfX  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); bV6V02RF  
int nCount = input.readInt(); 2 Y+:,ud\  
nStartPos = new long[nCount]; a+ GJVJ  
nEndPos = new long[nCount]; doLNz4W  
for(int i=0;i<nStartPos.length;i++) wW5Yw i  
{ E9$H nj+m  
nStartPos = input.readLong(); B*79qq  
nEndPos = input.readLong(); C6^j#rl  
} D^?_"wjW  
input.close(); MLS;SCl  
} u)~s4tP4  
catch(IOException e){e.printStackTrace ();} 9rcI+q=E  
catch(Exception e){e.printStackTrace ();} Y[G9Vok VX  
} >r}Vf9 5[N  
]sL45k2W  
BS2?!;,8  
private void processErrorCode(int nErrorCode) N!c gN  
{ S(t{&+Wc  
System.err.println("Error Code : " + nErrorCode); +tU Q  
} w}`3 d@  
9XOyj5  
z<<Tk.65  
//停止文件下载 Gru ALx7  
public void siteStop() c;!9\1sr  
{ _yVPpA[a  
bStop = true; 4f {+pf^R  
for(int i=0;i<nStartPos.length;i++) c0[k T  
fileSplitterFetch.splitterStop(); 6Xa.0(h  
^73=7PZ  
 AP w6  
} }N,>A-P  
} e{!vNJ0`  
//负责部分文件的抓取 H(> M   
**FileSplitterFetch.java (oYW]c}G,  
*/ =DMbz`t  
package NetFox; 28oJFi]  
UvBnf+,  
ug&92Hdvy3  
import java.io.*; XeU<^ [  
import java.net.*; &HL{LnLP@/  
oD0EOT/E  
>FF1)~  
public class FileSplitterFetch extends Thread { [h HG .  
jVYH;B%%z  
%g w{[ /[A  
String sURL; //File URL 6?o>{e7n^  
long nStartPos; //File Snippet Start Position 6mHhC?  
long nEndPos; //File Snippet End Position asz?p\k:bC  
int nThreadID; //Thread's ID RGp'b  
boolean bDownOver = false; //Downing is over 2 ~-( A  
boolean bStop = false; //Stop identical n(R_#,Hs  
FileAccessI fileAccessI = null; //File Access interface w1i?# !|  
)eR$:uO  
dtTlIhh1V  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException ~6d5zI4\  
{ 9p*-?kPb  
this.sURL = sURL; =l,#iYJP8  
this.nStartPos = nStart; q[c Etp28h  
this.nEndPos = nEnd; ^:z7E1 ~  
nThreadID = id; Y iZx{5  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 v<&v]!nF  
} sykFSPy`'  
e /94y6*>  
K7RKF$Z\  
public void run() oAz<G  
{ W ~NYU  
while(nStartPos < nEndPos && !bStop) 7$_ :sJ  
{ 7I3:u+  
.bfST.OA  
 ?Ib}  
try{ b:Dg}  
URL url = new URL(sURL); \h#9oPy  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); (\& 62B1  
httpConnection.setRequestProperty("User-Agent","NetFox"); Vp7b4n<  
String sProperty = "bytes="+nStartPos+"-"; zlkWU  
httpConnection.setRequestProperty("RANGE",sProperty); -*3(a E  
Utility.log(sProperty); \EI#az=I  
B_&^ER5j  
rzT{-DZB[4  
InputStream input = httpConnection.getInputStream(); all*P #[X  
//logResponseHead(httpConnection); ]M\q0>HoJ  
V6*?$o  
8ds}+TtbY  
byte[] b = new byte[1024]; )X%oXc&C|  
int nRead; P` ]ps?l  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 8\_*1h40s  
{ qTy v.#{y  
nStartPos += fileAccessI.write(b,0,nRead); hr~.Lj5^W  
//if(nThreadID == 1) @C_ =*  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2sun=3qb  
} 4Py3I9  
UkfA}b^@v  
4)nt$fW  
Utility.log("Thread " + nThreadID + " is over!"); tN!Bvj:C[M  
bDownOver = true; 3:AU:  
//nPos = fileAccessI.write (b,0,nRead); #Fzb8Yo  
} mz-N{>k  
catch(Exception e){e.printStackTrace ();} @_Sp3nWdu  
} ^ZVO ql&  
} Yb9cW\lr  
0BDS_Rx  
w4A#>;Qu*  
//打印回应的头信息 PWG;&ma  
public void logResponseHead(HttpURLConnection con) 7LdzZS0OM  
{ fTgbF{?xh  
for(int i=1;;i++) }4KW@L[g  
{ '!@A}&]  
String header=con.getHeaderFieldKey(i); 8Fx]koP.  
if(header!=null) |^!Vo&T  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); /.@x 4cdS  
Utility.log(header+" : "+con.getHeaderField(header)); ?Cc :)  
else 3):?ZCw7y  
break; ^O \q3HA_4  
} :D4];d>1  
} 5M.Red.L  
DaDUK?  
UM\}aq=,  
public void splitterStop() yxY h?ka  
{ 'M-)Os "  
bStop = true; y#e ?iE@  
} Ays L-sqR  
2Pz5f  
D6:DrA:  
} kQ[Jo%YT?E  
I4:rie\hjC  
_.-#E$6s#q  
/* N'a?wBBR  
**FileAccess.java tWX7dspx/  
*//文件访问(定位,写) wPQ&Di*X}  
package NetFox; ^XNw$@&',  
import java.io.*; -;ER`Jqs,  
z L8J`W  
Yx 3|G  
public class FileAccessI implements Serializable{ /N%zwj/*  
g/B\ObY  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 v^\JWPR/  
RandomAccessFile oSavedFile; MYu`c[$jZ  
long nPos; ydyG}XI7V  
c dDY]"k  
SctJxY(}!  
public FileAccessI() throws IOException 1 yJ75/  
{ SdSgn|S  
this("",0); bq: [Nj  
} n{$}#NdV  
TH>,v  
=-m(\ }  
public FileAccessI(String sName,long nPos) throws IOException OQ,}/  
{ W[fT R?n  
oSavedFile = new RandomAccessFile(sName,"rw"); Nuo^+z E   
this.nPos = nPos; Eo Ko   
oSavedFile.seek(nPos); LS{bg.e  
} 1]Lhk?4t  
BPh".RJ  
HM 90Sb  
public synchronized int write(byte[] b,int nStart,int nLen) ~;!BDLMC6  
{ V07VwVD  
int n = -1; @"0uM?_)-  
try{ )# p.`J  
oSavedFile.write(b,nStart,nLen); .Nk}Z9L]k  
n = nLen; 3jXR"@Z-  
} J ZA*{n2  
catch(IOException e) e|JIrOnc  
{ e) ]RA?bF  
e.printStackTrace (); %6N)G!P  
} [0wP\{%  
blUY.{NN3  
l\_x(BH  
return n; "A]?M<R  
} o:H'r7N  
Y}S.37|+^  
3hH>U%`-  
} 9QC< E|  
D(!;V KH  
O%52V|m}{  
/* *^uGvJXF  
**SiteInfoBean.java :Jm!=U%'Z  
*/ ^]i" H|(x  
package NetFox; ?P%|P   
<o ~t$TH  
&{BBxv)y  
public class SiteInfoBean {  k~{Fnkt  
> n1h^AW  
[#IBYJ.6  
private String sSiteURL; //Site's URL [;*\P\Xih  
private String sFilePath; //Saved File's Path 40R"^*  
private String sFileName; //Saved File's Name VZHr-z$6n  
private int nSplitter; //Count of Splited Downloading File Bpm,mp4g\#  
0e)lY='^_  
}M^_Z#|,  
public SiteInfoBean() xUQdVrFU  
{//nSplitter的缺省值为5 z1kBNOr  
//default value of nSplitter is 5 g ,`F<CF9  
this("","","",5); )sRN!~  
} j{)fC]8H  
U&`6&$]  
v: giZxR  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) !;TR2Zcn  
{ kp'b>&9r  
sSiteURL= sURL; J9NsHr:A[  
sFilePath = sPath; ";756'>  
sFileName = sName; JR] )xPI`  
this.nSplitter = nSpiltter; Kq$:\B)<c  
cD5w| rm?i  
WUzS lZq  
} hK Fk$A  
5QKRI)XpZ  
mlD%d!.  
public String getSSiteURL() 0 4P.p6  
{  c^rC8E  
return sSiteURL; ={\![{L  
} DE5d]3B  
C?8PT/  
NS h%t+XU]  
public void setSSiteURL(String value) 3T"2S[gT  
{ P a3{Ds  
sSiteURL = value; I+*osk  
} 0K&_D)  
>ze>Xr'm5=  
BHEs+ e0  
public String getSFilePath() xT:qe  
{ dUI3erO  
return sFilePath; 3(aRs?/ O  
} MgHOj   
D% oueW  
bh{E&1sLh  
public void setSFilePath(String value) <_=JMA5  
{ G}182"#4  
sFilePath = value; KrJ5"1=  
} #c6ui0E%;t  
lq~Gc M  
"(Mvl1^BT  
public String getSFileName() >s;oOo+5  
{ EV:_Kx8fP  
return sFileName; Vp|2wlFE-  
} k&WUv0  
JtSuD>H`"  
@P*ylB}?Q  
public void setSFileName(String value) ~o:rM/!Ba  
{ Lc58lV=  
sFileName = value; P;^y|0N m  
} 8w03{H 0  
E7V38Z  
MomLda V9Q  
public int getNSplitter() _TtX`b_Z  
{ mfj4`3:NV  
return nSplitter; \El|U#$u'  
} /7c2OI=\  
<sm#D"GpP  
r3n=<l!Jr  
public void setNSplitter(int nCount) UAnB=L,.\  
{ fx]\)0n  
nSplitter = nCount; ~C%2t{"  
} _`TepX R  
} Rbx97(wK  
kJHr&=VO~  
VI(RT-S6  
/* i6-wf Gs;  
**Utility.java Mr$# e  
*/  aeEw#  
package NetFox; 3Cq6h;!#  
^RYn8I  
);0<Odw%.  
public class Utility { =6.8bZT\  
qlz( W  
83mlZ1jQz  
public Utility() NYWG#4D  
{ m"96:v  
;M%oQ> ].[  
u)<Ysx8G  
} l0qdk #v  
pYYqGv^oa  
//线程睡眠 A M>Yj  
public static void sleep(int nSecond) ck(CA(_  
{ j)g_*\tQ  
try{ i58ZV`Rk`  
Thread.sleep(nSecond); Zkf 3t>[  
} *54>iO- c  
catch(Exception e) ^</65+OT+  
{ r~ZS1Tp  
e.printStackTrace (); mle_*Gy8  
} r^?)F?n!  
} L!CX &  
uPa/,"p  
//日志 F?*Dr  
public static void log(String sMsg) 43vGgGW  
{ v_y!Oh?EG  
System.err.println(sMsg); {Q{lb(6Ba  
} z7O Z4R:  
0!9?H1>  
^+(A&PyP?  
public static void log(int sMsg) y0/WA4,  
{ "6NFe!/Y$*  
System.err.println(sMsg); FQ ;4'B^k]  
} <dju6k7uz  
} #E- VW  
k98< s  
8QkWgd7y  
/* kvMk:.  
**TestMethod.java ?b!CV   
*/ tebWj>+1c  
package NetFox; N&6_8=3z  
Z7tU0  
.`oJcJ  
public class TestMethod { 8@Egy%_  
/#S4espE  
:z0s*,QH  
public TestMethod() LydbP17K}  
{ ///xx/weblogic60b2_win.exe \_m\U.*  
try{ w.4u=e >Z4  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); \zk?$'d  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); :FX'[7;p  
SiteFileFetch fileFetch = new SiteFileFetch(bean); +-Z"H)  
fileFetch.start(); ,pQ'w7  
} MgJ%26TZ  
catch(Exception e){e.printStackTrace ();} DhtU]w}  
!Iw{Y'  
{] t\`fjrg  
} )GiFkG  
p)?qJ2c|  
Cm,*bgX  
public static void main(String[] args)  ltCwns  
{ %8}WX@SB  
new TestMethod(); ua]\xBWx  
} YtwmlIar`  
} \Dvl%:8   
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
如果您在写长篇帖子又不马上发表,建议存为草稿
认证码:
验证问题:
10+5=?,请输入中文答案:十五