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
  • 12040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
/* G9Tix\SpF  
**SiteFileFetch.java 12dW:#[  
*/ |"v{RC0  
package NetFox; :`1g{8.+  
import java.io.*; eCD,[At/  
import java.net.*; ~7'.{VrU  
&Sa~Wtm|*  
rK|&u v*b  
public class SiteFileFetch extends Thread { Ya 4$7|(  
]{^vs'as\  
V.:A'!$#  
SiteInfoBean siteInfoBean = null; //文件信息Bean m28w4   
long[] nStartPos; //开始位置  ?Nql7F4  
long[] nEndPos; //结束位置 FoCkTp+/  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 U:hC! t:  
long nFileLength; //文件长度 " SqKS,J  
boolean bFirst = true; //是否第一次取文件 Y3>\;W*?  
boolean bStop = false; //停止标志 3 ?~+5DU  
File tmpFile; //文件下载的临时信息 zAJUL  
DataOutputStream output; //输出到文件的输出流 3HR]TQ%r  
+Ob#3PRy  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) );H[lKy  
public SiteFileFetch(SiteInfoBean bean) throws IOException >nEnX  
{ T]-~?;Jh8  
siteInfoBean = bean; [)vwg`]   
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); Cq;d2u0)o$  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); w[YbL2p  
if(tmpFile.exists ()) ygt)7f5  
{ >]8.xkQq  
bFirst = false; 4LJ}>e  
read_nPos(); X{9o8 *V  
} j],.`Y  
else tta0sJ8 i  
{ tdF[2@?+  
nStartPos = new long[bean.getNSplitter()]; aZ`ags ofk  
nEndPos = new long[bean.getNSplitter()]; ; @~*z4U  
} :Xh`.*{EX  
QC,(rB  
5V8C+k)  
:9#{p^:o  
} Fxx2vTV4ag  
/+O8A}  
B?Sfcq-  
public void run() 1R9? [RE  
{ F@roQQu  
//获得文件长度 Nj&%xe>].  
//分割文件 '$-,;vnP0  
//实例FileSplitterFetch pY#EXZ#   
//启动FileSplitterFetch线程 ;XQ lj?:  
//等待子线程返回 KXCmCn  
try{ Q9tE^d+%  
if(bFirst) ^QR'yt3e  
{ ;o459L>sW  
nFileLength = getFileSize(); w1(06A}/  
if(nFileLength == -1) i9U_r._qj;  
{ G<6grd5PP  
System.err.println("File Length is not known!"); $50"3g!Y  
} }(EOQ2TI  
else if(nFileLength == -2) z}2e;d 7  
{ m@yVG|eP#  
System.err.println("File is not access!"); G11.6]?Gg  
} Jd"s~n<>K  
else N4|q2Jvj6  
{ lNVAKwW2#  
for(int i=0;i<nStartPos.length;i++) )Hm[j)YI  
{ X`QW(rq  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); NVWeJ+w  
} bMOM`At>z  
for(int i=0;i<nEndPos.length-1;i++) |hQ|'VCN  
{ HKN"$(Q  
nEndPos = nStartPos[i+1]; qpqz. {\  
} 7qK0!fk5  
nEndPos[nEndPos.length-1] = nFileLength; 3N0X?* (x|  
} E?4@C"Na  
} q)xl$*g  
v |2q2bz  
Q4LlToHn  
//启动子线程 `G0rF\[  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; @"Fp;Je\bN  
for(int i=0;i<nStartPos.length;i++) w[oQ}5?9'  
{ 3b\8907  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ;s. 5\YZ"k  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), aX'g9E  
nStartPos,nEndPos,i); ;VlZd*M?  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 1(7.V-(G  
fileSplitterFetch.start(); m?% H<4X  
} BRXb<M^;_  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), &z X 3  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); + >gbZ-S  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", [^}>AC*im  
nEndPos = " + nFileLength); qTh='~m4[  
// fileSplitterFetch[nPos.length-1].start(); Fxth> O`$  
A~GtK\=;  
Ld3Bi2d|  
//等待子线程结束 ' raB  
//int count = 0; ) UDJ[pL@  
//是否结束while循环 ml33qXW:  
boolean breakWhile = false; ?}3PJVy?  
.4C[D{4  
M?~<w)L}  
while(!bStop) eMl]td rI  
{ Jt>[]g$  
write_nPos(); 8Z4?X%  
Utility.sleep(500); %][$y 7  
breakWhile = true; <.=#EV^i  
2~&hstd%  
L_lDFF  
for(int i=0;i<nStartPos.length;i++) L740s[,`o#  
{ &Ky u@Tt  
if(!fileSplitterFetch.bDownOver) <f.>jjwFE  
{ JXLWRe  
breakWhile = false; X=p3KzzX  
break; Y7kb1UG  
} Vy% :\p+  
} 7moElh v  
if(breakWhile) xjK_zO*dLq  
break; 2l)9Lz=;L  
5Q$r@&qp  
G_^iR-  
//count++; ^YG7dd_  
//if(count>4) 5&?KW)6 Rz  
// siteStop(); (3N"oE.b]  
} .A*VLF*m  
oGJ*Rn)Z  
5qd_>UHp  
System.err.println("文件下载结束!"); XYb^C s;  
} KZrMf77=  
catch(Exception e){e.printStackTrace ();} iF [?uF  
} 4z9#M;q T  
c:llOHA  
=CjNtD2]  
//获得文件长度 &}nBenYp  
public long getFileSize() YXX36  
{ J+71FP`ZH  
int nFileLength = -1; &SjHrOG?  
try{ .|-l+   
URL url = new URL(siteInfoBean.getSSiteURL()); hg?j)jl|  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); XVrm3aj(m  
httpConnection.setRequestProperty("User-Agent","NetFox"); so!w!O@@  
1tc]rC4h  
h6\3vfj^f  
int responseCode=httpConnection.getResponseCode(); <'}b*wUB  
if(responseCode>=400) p<=(GY-  
{ v@fe-T&0  
processErrorCode(responseCode); O}K_l1  
return -2; //-2 represent access is error "?.'{,Q  
} Q%& _On  
WxVn&c\  
':4}O#  
String sHeader; +}7Ea:K   
>bfYy=/  
RIy5ww}3|  
for(int i=1;;i++) s&dO/}3uR]  
{ MX!u$ei  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); "U% n0r2  
//Utility.log(in.readLine()); EjR_-8@FK  
sHeader=httpConnection.getHeaderFieldKey(i); CxbSj,  
if(sHeader!=null) *GbVMW[A>  
{ RgB6:f,  
if(sHeader.equals("Content-Length")) 'yPCZ`5H(  
{ .3lGX`d{  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); .KLm39j(  
break; nT.L}1@  
} aO.\Qe+j  
} w4e%-Ln  
else bA@ /B'  
break; =tr1*s{  
} RzA2*]%a  
} K*R)V/B/l  
catch(IOException e){e.printStackTrace ();} `fBG~NDw  
catch(Exception e){e.printStackTrace ();} -}{%Q?rYj  
ixIV=#  
0jxO |N2)  
Utility.log(nFileLength); lx\qp`w  
0U82f1ei  
cGgM8  
return nFileLength; }>MP{67Dm  
} )uQ-YC('0  
(^sh  
L`9TB"0R+  
//保存下载信息(文件指针位置) l GdM80f  
private void write_nPos() ]2Sfkl0  
{ , CJAzGBS  
try{ 4. 1rJa  
output = new DataOutputStream(new FileOutputStream(tmpFile)); [YC=d1F5  
output.writeInt(nStartPos.length); 9$7&URwSDI  
for(int i=0;i<nStartPos.length;i++) &/Eg2  
{ Lw*;tL<,  
// output.writeLong(nPos); 9[cp7 Rcb  
output.writeLong(fileSplitterFetch.nStartPos); fCgBH~w,9  
output.writeLong(fileSplitterFetch.nEndPos); %1Bn_  
} [Q4_WKI0T  
output.close(); wYZT D*A2h  
} C=fsJ=a5;  
catch(IOException e){e.printStackTrace ();} iO!27y  
catch(Exception e){e.printStackTrace ();} tIq>Oojdx  
} "pt+Fe|@c;  
Dt.0YKF  
aSc{Ft/O  
//读取保存的下载信息(文件指针位置) 6!P`XTTE  
private void read_nPos() P DRnW  
{ T}C2e! _O  
try{ Dc08D4   
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); (+|X<Bl:`  
int nCount = input.readInt(); V,V*30K5  
nStartPos = new long[nCount]; 6}ce1|mkg/  
nEndPos = new long[nCount]; }$o*  
for(int i=0;i<nStartPos.length;i++) IUOxGJ|rO  
{ L2KG0i`+  
nStartPos = input.readLong(); -x{dc7y2  
nEndPos = input.readLong(); !7}IqSs  
} JkZ50L  
input.close(); 25UYOK}!  
} _eGT2,D5r  
catch(IOException e){e.printStackTrace ();} R)ERx z#  
catch(Exception e){e.printStackTrace ();} w{pUUo:<  
} <lUOJV{&\  
_ `H.h6h  
K&*iw`  
private void processErrorCode(int nErrorCode) z9[[C^C  
{ YRPm^kW  
System.err.println("Error Code : " + nErrorCode); 7 _`L$<-n  
} J , V  
pgT9hle/  
t)` p@]j  
//停止文件下载 m9Ax\lf  
public void siteStop() OFA{ KZga  
{  3P1&;  
bStop = true; ~ |6dH  
for(int i=0;i<nStartPos.length;i++) :M06 ;:e  
fileSplitterFetch.splitterStop(); (ab{F5  
!BDUv(  
2K;#Evn'j  
} 7c-Gm R2  
} iZaeoy  
//负责部分文件的抓取 "NDxgJ%J35  
**FileSplitterFetch.java X 7=fX~s  
*/ 7|YN:7iA  
package NetFox; @:Di`B_{  
[]|;qHhC~(  
D3`}4 A  
import java.io.*; Br}h/!NU/  
import java.net.*; \i!Son.<  
,|+Gls  
vv6?V#{  
public class FileSplitterFetch extends Thread { j Fma|y  
EM@ ;3.IO  
ibJHU@l  
String sURL; //File URL 2#3^skj  
long nStartPos; //File Snippet Start Position v!H:^!z  
long nEndPos; //File Snippet End Position 7 {f_fkbs  
int nThreadID; //Thread's ID [*)Z!)  
boolean bDownOver = false; //Downing is over ZPHXzi3j  
boolean bStop = false; //Stop identical btH _HE  
FileAccessI fileAccessI = null; //File Access interface c"7j3/p  
FW8-'~  
rz%<AF Z  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException \ p4*$  
{ -?<4Og[^  
this.sURL = sURL; V >Hf9sZ  
this.nStartPos = nStart; q@n^ZzTx  
this.nEndPos = nEnd; [|[>}z:  
nThreadID = id; q]\X~ 9#  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 SHD^}?-|  
} . w H*sb  
Y#FO5O%W  
+ E/y ~s  
public void run() Q6IQV0{p  
{ ,LZX@'5  
while(nStartPos < nEndPos && !bStop) =p@8z /u  
{ ;Wc4qJ.@  
(vc|7DX M  
HSN8O@dy  
try{ 8!mc@$Z  
URL url = new URL(sURL); I;7nb4]AmF  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 1tB[_$s  
httpConnection.setRequestProperty("User-Agent","NetFox"); BByCM Y  
String sProperty = "bytes="+nStartPos+"-"; .R5y:O  
httpConnection.setRequestProperty("RANGE",sProperty); 99=s4*xzM  
Utility.log(sProperty); R^*K6Ad  
dRI^@n  
-h#mn2U~3r  
InputStream input = httpConnection.getInputStream(); zP!J/}z  
//logResponseHead(httpConnection); >O7~h[FN  
p@YB?#Im  
Zj*\"Ol  
byte[] b = new byte[1024]; PWB(5 f?  
int nRead; 7\XE,;4>  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 9b;A1gu  
{ QvLZg  
nStartPos += fileAccessI.write(b,0,nRead); Sm-wH^~KA  
//if(nThreadID == 1) FJNF%a)x2I  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ?":'O#E  
} >u0w.3r#  
C`V)VJM  
T*~H m  
Utility.log("Thread " + nThreadID + " is over!"); % UZVb V  
bDownOver = true; ^j)BKD-  
//nPos = fileAccessI.write (b,0,nRead); K93p"nHN  
} ]"~51HQZ  
catch(Exception e){e.printStackTrace ();} X"q!Y#)  
} k~3.MU  
} Gi FXX  
KCuG u}  
B*1W`f  
//打印回应的头信息 nkDy!"K  
public void logResponseHead(HttpURLConnection con) |3hY6aty  
{ =Z G:x<Hg  
for(int i=1;;i++) |o<8}Nja6  
{ tMp=-"  
String header=con.getHeaderFieldKey(i); RDM`9&V!jp  
if(header!=null) J*fBZ.NO  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ILwn&[A0  
Utility.log(header+" : "+con.getHeaderField(header)); otJ!UfpR8  
else ($nrqAv4  
break; ~8T(>!hE1h  
} ,8MLoZ _  
} BZv+H=b  
v"^~&q0x  
w}R~C   
public void splitterStop() $gpG%Qj  
{ fyWO  
bStop = true; *&Lq!rFS  
} Cx_Q: 6T  
!0,Mp@ j/  
,TJ D$^  
} ;z~n.0'  
sZ<9A Xk-E  
CjIu[S1%  
/* ]rN5Ao}2  
**FileAccess.java . lgPFr6X  
*//文件访问(定位,写) *Vw\'%p*  
package NetFox; 8qEK+yi,  
import java.io.*; Rli:x  
A@*:<Hs%  
U-k VNBs  
public class FileAccessI implements Serializable{ Q7X3X,  
B[4pX +f  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 k n[Y   
RandomAccessFile oSavedFile; ;a{:%t  
long nPos;  Ez~'^s@  
\dQx+f&t  
U$dh1;  
public FileAccessI() throws IOException h].~#*  
{ COzyG.R.  
this("",0); `(6r3f~XJ  
} G rmzkNlN  
kql0J|P?  
YXurYwV  
public FileAccessI(String sName,long nPos) throws IOException Em 6Qe  
{ ORXm&z)  
oSavedFile = new RandomAccessFile(sName,"rw"); P + "Y  
this.nPos = nPos; jw}}^3.  
oSavedFile.seek(nPos); l1U=f]  
} JO<wK  
K$K^=> I"o  
)Or  .;  
public synchronized int write(byte[] b,int nStart,int nLen) :'F}Dy  
{ 38DT2<qC  
int n = -1; 0$+fkDf  
try{ G 0O#/%%  
oSavedFile.write(b,nStart,nLen); jn >d*9u  
n = nLen; ^.k |SK`U  
} BBG3OAyg_  
catch(IOException e) Io4(f  
{ @yXfBML?]  
e.printStackTrace (); ofYlR|  
} p Dx-2:}  
e!Y0-=?nf#  
B+C);WQ,  
return n; 8}X5o]Mv  
} uXDq~`S  
g,o?q:FL  
'0y9MXRT  
} mbnV[  
9Y>8=#.c  
kF;D BN  
/* HHX-1+L  
**SiteInfoBean.java r:&` $8$  
*/ 53-v|'9'  
package NetFox; ;z M*bWh9  
r<F hY  
R8rfM?"W  
public class SiteInfoBean { \0lnxLA  
*BuUHjTv  
@/ZF` :   
private String sSiteURL; //Site's URL g;$Xq)Dd  
private String sFilePath; //Saved File's Path ;S0Kh"A  
private String sFileName; //Saved File's Name 8]4U`\k4  
private int nSplitter; //Count of Splited Downloading File 63`{.yZ*z  
V-n&oCS+f  
SS`qJZ|w  
public SiteInfoBean() F:y[@Yn  
{//nSplitter的缺省值为5 F":r4`5D"K  
//default value of nSplitter is 5 `qd+f{Q  
this("","","",5); b=~i)`  
} D +_oVob\  
~4P%%b0,o  
K=!Bh*  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) '13ZX:  
{ ) ri}nL.  
sSiteURL= sURL; p.+ho~sC,.  
sFilePath = sPath; bAKiq}xG%i  
sFileName = sName; Ig3;E+*>  
this.nSplitter = nSpiltter; :qChMU|Y6  
d*)CT?d&  
nhIa175'  
} kJW N.  
#Z6'?p9  
L?5Ck<!xG  
public String getSSiteURL() hx/N1 x  
{ "4vy lHIo  
return sSiteURL; cUTE$/#s  
} %QKZT=}  
#2r}?hP/m  
 /'31w9  
public void setSSiteURL(String value) +w=AJdc  
{ o9cM{ya/>  
sSiteURL = value; 5M9 I,  
} oB74y  
DjSbyXvrg  
'v]u#/7a  
public String getSFilePath() lA>DS#_  
{ f!O{%ev  
return sFilePath; )(y) A[  
} pb#?l6x$+  
]4;PR("aU  
}$bF 5&  
public void setSFilePath(String value) <dW]\h?)  
{ %W@v2  
sFilePath = value; sKlDu  
} ooUk O  
N^Bo .U0\  
n_3O-X(  
public String getSFileName() 2tal  
{ ^pJ!isuqu  
return sFileName; `7/Y@}n  
} hWH:wB  
:1Q!$  m  
+la2n(CAK  
public void setSFileName(String value) wn)JXR  
{ ~I{n^Q/a  
sFileName = value; +-E~6^>  
} 1Bpv"67  
<{~6}6o  
;j4?>3  
public int getNSplitter() i;!H!-sM  
{ ID#I`}h.k  
return nSplitter; 765p/**  
} -?(E_^ng  
r#xg#uoj  
0_CN/5F  
public void setNSplitter(int nCount) x' .:&z  
{ }1>[  
nSplitter = nCount; 2(/g}  
} i+gQE!  
} 3E 3HL7  
,\qs4&  
;]_o4e6\p  
/* ?.D3'qv  
**Utility.java =zyC-;r!  
*/ 5 Kkdo!z  
package NetFox; V*W;OiE_ 3  
8P=o4lO+  
C`5  
public class Utility { OK\A</8r  
w: >5=mfk  
Y-7^o@y  
public Utility() q7"7U=W0  
{ / ~^rr f  
Yot?=T};3{  
D$T%\ P  
} nxr!`^Mne  
ATR!7i\|  
//线程睡眠 }fKSqB]T-  
public static void sleep(int nSecond)  =|9H  
{ 9'r:~ O  
try{ R9B&dvG  
Thread.sleep(nSecond); +"1NC\<*  
} {l |E:>Q2  
catch(Exception e) T8^5=/  
{ q `pP$i:  
e.printStackTrace (); |^A;&//  
} .jj$Kh q]  
} QR>gt;  
U*3uq7  
//日志 5< ja3  
public static void log(String sMsg) u;`U*@  
{ /tUy3myJ  
System.err.println(sMsg); i\dc>C ;  
} 3\Xbmq8}  
0Q^Ikiv   
CxfRV L`7  
public static void log(int sMsg) A\#iXOd  
{ Aj0Tfdxy  
System.err.println(sMsg); ;$z$@@WC  
} P LueVz  
} uV=Qp1~  
v'BZs   
nB!&Zq  
/* $#]]K  
**TestMethod.java L: z?Zt)|  
*/ r fq;%C  
package NetFox; D&S26jrZ  
# 0Lf<NZ  
;s52{>&F]  
public class TestMethod { 9k6r_G"  
^.>jG I%rB  
I}t#%/'YA  
public TestMethod() }X=[WCK U  
{ ///xx/weblogic60b2_win.exe ?yj6CL(,  
try{ Pcw6!xH  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); $H-!j%hV  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); TYQwy*  
SiteFileFetch fileFetch = new SiteFileFetch(bean); qkC/\![@  
fileFetch.start(); VH[hsj  
} Qm/u h  
catch(Exception e){e.printStackTrace ();} DoeiW=  
0fYj4`4=n  
46 PoM  
} 0A( +ZMd  
=" g*\s?r  
K#U<ib-v  
public static void main(String[] args) mL4]l(U  
{ J2^'Xj_V  
new TestMethod(); x l#LrvxI  
} }oNhl^JC  
} [h,QBz  
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