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
  • 11112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
/* 3&`LVhx  
**SiteFileFetch.java ?/3'j(Gk  
*/ ^W#161&  
package NetFox; Z/G`8|A  
import java.io.*; 8=kIN-l_  
import java.net.*; #X 1 GL  
X?f\j"v  
\P~ h0zg?  
public class SiteFileFetch extends Thread { \%BII>VS  
m-u3^\'  
:LrB9Cf$n  
SiteInfoBean siteInfoBean = null; //文件信息Bean :[\M|iAo  
long[] nStartPos; //开始位置 rvEX ;8TS  
long[] nEndPos; //结束位置 j{&*]QTN  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 dQ#$(<v[  
long nFileLength; //文件长度 j;TXZ`|(  
boolean bFirst = true; //是否第一次取文件 4 x|yzUx  
boolean bStop = false; //停止标志 1RHFWK5Si  
File tmpFile; //文件下载的临时信息 H;w8[ImK  
DataOutputStream output; //输出到文件的输出流 FHOF 6}if  
X iW~? *Z  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) X\Gbs=sf6  
public SiteFileFetch(SiteInfoBean bean) throws IOException Gv\39+9 =  
{ i0q<,VSl$_  
siteInfoBean = bean; lD9QS ;  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); KATu7)e&~^  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); oU`{6 ~;  
if(tmpFile.exists ()) 2p|ed=ly%  
{ (pv6V2i  
bFirst = false; y?Cq{(  
read_nPos(); ,azBk`$iQr  
} v{r,Wy3  
else nI_UL  
{ 0+{CN|0  
nStartPos = new long[bean.getNSplitter()]; 8.WZC1N  
nEndPos = new long[bean.getNSplitter()]; $ VTk0J-W  
} u; G-46  
SPu+t3  
(Q(=MEar  
8*&|Q1`K:  
} _jWGwO  
g>*P}r~;^b  
ihp>cl?  
public void run() /< -+*79G  
{ M!4}B  
//获得文件长度 .o(S60iH!(  
//分割文件 D;! aix3  
//实例FileSplitterFetch O&g$dK!Rad  
//启动FileSplitterFetch线程 2%_UOEayU  
//等待子线程返回 +bdjZD3  
try{ L)"E_  
if(bFirst) JRr'81\  
{ h?7@]&VJ  
nFileLength = getFileSize(); b}HwvS:  
if(nFileLength == -1) 01w}8a(  
{ zBjbH=  
System.err.println("File Length is not known!"); |V-)3 #c  
} H: rrY  
else if(nFileLength == -2) / LC!|-1E  
{ wA< Fw )  
System.err.println("File is not access!"); BTnrgs#[  
} '*=kt  
else 3)*Twqt  
{ 3[Z7bhpV  
for(int i=0;i<nStartPos.length;i++) A}W}H;8x  
{ v|IG G'r  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); _1ax6MwX  
} >NJ`*M  
for(int i=0;i<nEndPos.length-1;i++) $s<bKju  
{ AGMrBd|J{  
nEndPos = nStartPos[i+1]; jM[]Uh  
} uRnSwJ"hE  
nEndPos[nEndPos.length-1] = nFileLength; ?#gYu %7DN  
} >A.m`w  
} 2)T.Ci cx  
+`&-xq76  
M32Z3<  
//启动子线程 l<-0@(x)  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ov|/=bzro  
for(int i=0;i<nStartPos.length;i++) WUK{st.z  
{ aTFT'(O,  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), m\eYm;R Vj  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ~8tb^  
nStartPos,nEndPos,i); 3:MAdh[w  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); - p*j9 z  
fileSplitterFetch.start(); N VBWF  
} d9pZg=$8  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), tdi^e;:?  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); n-x%<j(Xf  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 7-j=he/  
nEndPos = " + nFileLength); Om5+j:YM  
// fileSplitterFetch[nPos.length-1].start(); #,;X2%c  
#xNXCBl]O  
\9%RY]TK3  
//等待子线程结束 ICm/9Onh&  
//int count = 0; 4h$W4NJK  
//是否结束while循环 JXAH/N& i  
boolean breakWhile = false; (( {4)5}  
XAb-K?)   
\[Q*d  
while(!bStop) |m>{< :  
{ 0u=FlQ }h  
write_nPos(); EL:Az~]V  
Utility.sleep(500); uoMDf{d  
breakWhile = true; 859ID8F  
=*=qleC3  
Zd <8c^@  
for(int i=0;i<nStartPos.length;i++) @f%q ,:  
{ @ $2xiE.[  
if(!fileSplitterFetch.bDownOver) aP`V  
{ q%hxU.h  
breakWhile = false; !_pryNcb  
break; IiB"F<&[j{  
} +^<-;/FZue  
} Av,E|C  
if(breakWhile) UlH;0P?  
break; +&qj`hA-b  
o 4cqLM u  
ES9|eo6  
//count++; &vV_,$  
//if(count>4) /2fQM_ ,P  
// siteStop(); MB!$s_~o#L  
} 5o2|QL  
c~v(bK  
F8OE  
System.err.println("文件下载结束!"); 1zWEK]2.R  
} .!yw@kg  
catch(Exception e){e.printStackTrace ();} I1fUV72  
} e>Q_&6L  
b^C2<'  
'G8.)eTA'  
//获得文件长度 [.LbX`K:  
public long getFileSize() B^lm'/,@  
{ (C60HbL  
int nFileLength = -1; zMbz_22*  
try{ U9%#(T$  
URL url = new URL(siteInfoBean.getSSiteURL()); ofHe8a8  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 4 t< mX  
httpConnection.setRequestProperty("User-Agent","NetFox"); rh$q]  
+5oK91o[y  
bqSp4TI  
int responseCode=httpConnection.getResponseCode(); Fpckb18}(O  
if(responseCode>=400) +lED6 ]+%  
{ 6\GL|#G  
processErrorCode(responseCode); W>T6Wlxu`6  
return -2; //-2 represent access is error *WK0dn  
} pipqXe  
$|n#L6k  
+9[s(E?SY  
String sHeader; k/mO(i%qi  
\K%A}gnHe  
.vk|aIG  
for(int i=1;;i++) * v W#XDx  
{ V7q-Pfh!y  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); q}MPl2  
//Utility.log(in.readLine()); MrFi0G7u  
sHeader=httpConnection.getHeaderFieldKey(i); mrId`<L5l{  
if(sHeader!=null) 6ujePi <U  
{ #P5tTCM  
if(sHeader.equals("Content-Length")) !/wR[`s9w  
{ E'wJ+X9 +  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); :y8wv|m  
break; TYN~c(  
} 3e7P w`gLl  
} \&. ]!!Q  
else 1k?k{Ri  
break; iES?}K/q  
} iU9>qJ]  
} GEQ3r'B|  
catch(IOException e){e.printStackTrace ();} $9Asr07  
catch(Exception e){e.printStackTrace ();} F2Nb]f  
_7Rp.)[&  
t182&gpd`  
Utility.log(nFileLength); (OT&:WwW  
zcE[wM  
w;4FN'  
return nFileLength; \'.#of  
} NZ=`iA8)X  
P/;d|M(  
y;1l].L  
//保存下载信息(文件指针位置) 8e*1L:oB!  
private void write_nPos() h4lrt  
{ ZA Xw=O5  
try{ /R!/)sg  
output = new DataOutputStream(new FileOutputStream(tmpFile)); 3 F ke#t  
output.writeInt(nStartPos.length); Fg<rz&MR  
for(int i=0;i<nStartPos.length;i++) UqEpeLK  
{ :qL1jnR^  
// output.writeLong(nPos); ;8J+Q0V  
output.writeLong(fileSplitterFetch.nStartPos); 60@]^g;$I  
output.writeLong(fileSplitterFetch.nEndPos); 1Kc[ ).O1  
} 72;ot`  
output.close(); rXG?'jN  
} R0_O/o+{  
catch(IOException e){e.printStackTrace ();} QGpAG#M9?  
catch(Exception e){e.printStackTrace ();} 568qdD`PS  
} 2c4x=%  
Q{"QpVY8  
WZ]f \S  
//读取保存的下载信息(文件指针位置) i1k#WgvZR  
private void read_nPos() [mJmT->  
{ `am]&0g^+(  
try{ sfw lv^  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); #CYDh8X<i  
int nCount = input.readInt(); d]<S/D'i  
nStartPos = new long[nCount]; LCf)b>C*  
nEndPos = new long[nCount]; /swNhDQ"o  
for(int i=0;i<nStartPos.length;i++) di5>aAJ)D  
{ N6wCCXd  
nStartPos = input.readLong(); ** !  
nEndPos = input.readLong(); Gn7P` t*.  
} mpysnKH  
input.close(); = gbB)u-Pc  
} xQK;3b  
catch(IOException e){e.printStackTrace ();} 9/_F  
catch(Exception e){e.printStackTrace ();} \n`)>-  
} Fy8$'oc  
#FQkwX'g  
!.}ZlA  
private void processErrorCode(int nErrorCode) 4<{]_S6"0y  
{ i9 Tq h  
System.err.println("Error Code : " + nErrorCode); W`2Xn?g  
} Y&JK*d  
n13#}i {tm  
"x P2GZ  
//停止文件下载 1*o=I-nOa  
public void siteStop() l=.h]]`;  
{ j|/4V  
bStop = true; a/v!W@Zz}  
for(int i=0;i<nStartPos.length;i++) X:1&Pdi  
fileSplitterFetch.splitterStop(); }aC@ov]2  
j68_3zpl  
7\xGMCctM  
} cEc_S42Z  
} LqA&@  
//负责部分文件的抓取 \)' o{l&  
**FileSplitterFetch.java +dgHl_,i  
*/ W-UMX',0zS  
package NetFox; 0/@ ^He8l  
zXRq) ;s  
-4IHs=`;I  
import java.io.*; /suW{8A(E  
import java.net.*; eKw!%97>  
#lld*I"d  
b)1v:X4Bv=  
public class FileSplitterFetch extends Thread { F\G-. 1  
AZgeu$:7p<  
THl={,Rw`  
String sURL; //File URL 1q7Y,whp  
long nStartPos; //File Snippet Start Position -fm1T|>#  
long nEndPos; //File Snippet End Position ~aZy52H_#.  
int nThreadID; //Thread's ID ooW;s<6  
boolean bDownOver = false; //Downing is over h]{V/  
boolean bStop = false; //Stop identical O"6 (k{`  
FileAccessI fileAccessI = null; //File Access interface i3[%]_eP.  
lNwqWOWy  
T1YCld  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException m2|%AD  
{ a#L:L8T;j  
this.sURL = sURL; pSC\[%K  
this.nStartPos = nStart; #FNSE*Y  
this.nEndPos = nEnd; o,D7$WzL  
nThreadID = id; <jwQ&fm)/R  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 "7X[@xX@  
} {k"t`uo_  
ah9P C7[  
uihU)]+@t/  
public void run() 7kDqgod^A  
{ 1](PuQm7+  
while(nStartPos < nEndPos && !bStop) "AcC\iq  
{ suF<VJ)&s  
](2\w9i%  
^_rBEyz@  
try{ Nm.G,6<J  
URL url = new URL(sURL); yPXa  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); c`E0sgp  
httpConnection.setRequestProperty("User-Agent","NetFox"); %UXmWXF4$  
String sProperty = "bytes="+nStartPos+"-"; C^^AN~ZD  
httpConnection.setRequestProperty("RANGE",sProperty); r\."=l  
Utility.log(sProperty); }gR!]Cs)^  
618k-  
#q mv(VB4  
InputStream input = httpConnection.getInputStream(); rY,zZR+@  
//logResponseHead(httpConnection); |mp~d<&  
[0M`uf/u  
oH ] _2[ !  
byte[] b = new byte[1024]; L#6!W  
int nRead; ^1mnw@04  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) N}\%r&KR=  
{ o0}kRL  
nStartPos += fileAccessI.write(b,0,nRead); f]C`]qg  
//if(nThreadID == 1) @yj$  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ARd*c?Om  
} nd #owjB  
WM8])}<L  
dMlJ2\ ]u  
Utility.log("Thread " + nThreadID + " is over!"); &)ED||r,  
bDownOver = true; E gD$A!6N8  
//nPos = fileAccessI.write (b,0,nRead); .:I^O[k  
} s$D"  
catch(Exception e){e.printStackTrace ();} 5>!I6[{  
} ^(+@uuBx  
} dzRnI*  
[fZhfZ)<  
lK%)a +2  
//打印回应的头信息 %F2T`?t:  
public void logResponseHead(HttpURLConnection con) >*]dB|2  
{ f>zd,|)At  
for(int i=1;;i++) P|tNmv[;  
{ 3'z L,WW  
String header=con.getHeaderFieldKey(i); nIEIb.-  
if(header!=null) f!K{f[aDa  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 9cXL4  
Utility.log(header+" : "+con.getHeaderField(header)); UpSa7F:Uw  
else ~o X`Gih  
break; U)6Ew4uRxV  
} \ !qe@h<  
} $g&_7SJ@  
-2qI2Z  
B".3NQ  
public void splitterStop() 9 K~X+N\  
{ &ev#C%Nu  
bStop = true; CsX@u#  
} @ QfbIP9  
#9rCF 3P  
c yH=LjgJf  
} c1M *w9o  
ZYLPk<<  
AvZO R  
/* %zYTTPLZ  
**FileAccess.java xFA+Zj BC  
*//文件访问(定位,写) 5h [<!f=  
package NetFox; R q .2  
import java.io.*; ,X)/ T!ff  
E^C [G)7n  
Im"8+756  
public class FileAccessI implements Serializable{ -?L3"rxAP  
#:E^($v  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 x }.&?m  
RandomAccessFile oSavedFile; Ch'e'EmI  
long nPos; ]vjMfT%]W  
4&<zkAMR  
*],= !  
public FileAccessI() throws IOException '-V[t yE  
{ l9+)h }  
this("",0); X&gXhr#dL\  
} tpQ8 m(  
|[iEi  
*t bgIW+h  
public FileAccessI(String sName,long nPos) throws IOException 7b*9 Th*a  
{ 7e:7RAX  
oSavedFile = new RandomAccessFile(sName,"rw"); "Z#MR`;&29  
this.nPos = nPos; }_fVv{D   
oSavedFile.seek(nPos); 4Ix~Feuph  
} S #C;"se  
50^CILKo7  
A"wso[{  
public synchronized int write(byte[] b,int nStart,int nLen) SN5Z@kK  
{ *qKf!&  
int n = -1; (G 9Ku 8Y  
try{ yPk s,7U  
oSavedFile.write(b,nStart,nLen); 1>)uI@?Rb  
n = nLen; ]htx9ds=  
} \79aG3MyK  
catch(IOException e) &`}ACTY'P  
{ (Eo#oX  
e.printStackTrace (); D6:"k 2  
} ]ZS/9 $  
tg;AF<VI  
7 aN}l QM  
return n; 1Ba.'~:  
} w -5_Ru  
Qy\K oo  
e^h4cC\^  
} Q32GI,M%B  
D' `[y  
DIWcX<s  
/* kYu"`_n}  
**SiteInfoBean.java mU;\,96#  
*/  V/t-  
package NetFox; 2l}3L  
0c]3 ,#  
$Hal]  
public class SiteInfoBean { 24I~{Qy  
yG:Pg MrB  
"FXT8Qxg  
private String sSiteURL; //Site's URL '_%`0p1  
private String sFilePath; //Saved File's Path =%0r_#F%=  
private String sFileName; //Saved File's Name X`0`A2 n  
private int nSplitter; //Count of Splited Downloading File Ew2ksZ>B]&  
K~ VUD(  
o%l|16DR  
public SiteInfoBean() ^w~Utx4  
{//nSplitter的缺省值为5 ;mXw4_{  
//default value of nSplitter is 5 $jN,] N~  
this("","","",5); 5uD'Kd$H  
} FQw@ @  
!;.nL-NQ  
xmwH~UWp  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) IfpFsq:  
{ K Z Q `  
sSiteURL= sURL; ?OdJ t  
sFilePath = sPath; 8EAkM*D w  
sFileName = sName; ?Q/9aqHe;  
this.nSplitter = nSpiltter; 0 hS(9y40  
Jc,{ n*  
so }Kb3n  
} pu5-=QN  
S@eI3Pk E  
z=a{;1A  
public String getSSiteURL() 2w67 >w\  
{ 3QD##Wr^  
return sSiteURL; $jNp-5+Q;  
} n##d!d|g  
|d=MX>i|G  
APY*SeI V  
public void setSSiteURL(String value) j:J{m0  
{ bId@V[9  
sSiteURL = value; ,XmyC7y<  
} S`&YY89{&  
4&^BcWqA*f  
M;F&Ix  
public String getSFilePath() :EZ"D#>y~  
{ +)-`$N  
return sFilePath; Avi8&@ya  
} Wf:I 0  
O)9{qU:[b  
VH5Vg We  
public void setSFilePath(String value) ;c;PNihg  
{ A+bU{oLr  
sFilePath = value; <e7  
} [";<YR7iRN  
u7kw/_f  
3*$)9'  
public String getSFileName() i;8tA !  
{ aC=D_JJ\  
return sFileName; )]3(ue  
} 5<KY}  
rg{|/ ;imT  
|HMpVT-;j  
public void setSFileName(String value) s7}46\/U  
{ RNn5,W  
sFileName = value; s6J`i&uu  
} 8^%Nl `_2B  
a5# B&|#q  
'{xPdN  
public int getNSplitter() $E]W U?U  
{ 7iBN!"G0  
return nSplitter; p@+r&Mg%W"  
} a'2^kds  
#Jqa_$\.  
o `N /w  
public void setNSplitter(int nCount) &o$Pwk\p/  
{ cN\Fgbt  
nSplitter = nCount; {expx<+4F  
} QSq0{  
} v\:P _J  
m'P,:S)=  
{ |[n>k   
/* aZ{]t:]  
**Utility.java #0;ULZ99aH  
*/ k(.6K[ b  
package NetFox; dCkk5&2n  
PhOtSml0  
y,QJy=?  
public class Utility { 0xQ="aXE  
t\%gP@?  
/"%(i#<)xs  
public Utility() "`4V ^1  
{ bI"_hvcFp  
kL1StF#p  
v8!Ts"  
} QBI;aG<+b>  
,aBo p#  
//线程睡眠 >=Pn\" j  
public static void sleep(int nSecond) -%eBip,'yl  
{ z<c%Xl\$%  
try{ .V Cfh+*J#  
Thread.sleep(nSecond); ^yo~C3 r~  
} O>H'o k  
catch(Exception e) fyE#8h_>4  
{ ^<VJ8jk<  
e.printStackTrace (); [|!A3o  
} K7CrRT3>6  
} IDIok~B=e  
M'D l_dx-  
//日志 J@vL,C)E6  
public static void log(String sMsg) t5Oeb<REz  
{ O.% $oV  
System.err.println(sMsg); :]hNw1e  
} J*} warf&  
s}3`%?,6y  
m=hUHA,p4  
public static void log(int sMsg) <)dHe:  
{ ;mAlF>6]\  
System.err.println(sMsg); {5, ]7=]  
} _^5OoE"}!  
} gx',~  
j aEUz5  
TC+L\7   
/* ZcLW8L  
**TestMethod.java WQ1~9#  
*/ muJR~4  
package NetFox; t/57LjV  
}pMd/|A,  
9cwy;au  
public class TestMethod { Z=&cBv4Fs  
f6r~Ycf,f  
p&nPzZQL(  
public TestMethod() ;"K;D@xzh]  
{ ///xx/weblogic60b2_win.exe %7y8a`}  
try{ zG. \xmp  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); vk&6L%_~a  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ^I CSs]}1  
SiteFileFetch fileFetch = new SiteFileFetch(bean); +'VSD`BR  
fileFetch.start(); Ey#7L M)  
} !\ 6<kQg#  
catch(Exception e){e.printStackTrace ();} f"}g5eg+  
ac%6eW0#  
7B)m/%>3s  
} 1R+/T  
FP_q?=~rFs  
qLYz-P'ik  
public static void main(String[] args) dz>2/'  
{ D,l&^diz  
new TestMethod(); QK`5KB(k'  
} nR(v~_y[V  
} 5Y(<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
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:
3+5=?,请输入中文答案:八 正确答案:八