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
  • 9617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
/* MnTJFo"  
**SiteFileFetch.java 8@,8j!$8G  
*/ H;{IOBo  
package NetFox; IN7Cpg~9%  
import java.io.*; P"f4`q  
import java.net.*; ,{2= nb[  
-an~&C5\  
 !U=o<)I  
public class SiteFileFetch extends Thread { l/-qVAd!q  
wQX18aF/#d  
t$z 5m<8  
SiteInfoBean siteInfoBean = null; //文件信息Bean pS+hE4D  
long[] nStartPos; //开始位置 [P*zm8b  
long[] nEndPos; //结束位置 &oxHVZJ  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 ~$d(@T&  
long nFileLength; //文件长度 D6,Ol4d  
boolean bFirst = true; //是否第一次取文件 kX%vTl7F  
boolean bStop = false; //停止标志 3/V0w|ZgD  
File tmpFile; //文件下载的临时信息 # 1 1<=3Yj  
DataOutputStream output; //输出到文件的输出流 *I.eCMDa  
[\-)c[/  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) `*",_RO;  
public SiteFileFetch(SiteInfoBean bean) throws IOException >u+%H vzc  
{ |eI!wgQx  
siteInfoBean = bean; wC?>,LOl  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); uj:1_&g  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); -% \LW1  
if(tmpFile.exists ()) 0K4A0s_R`  
{ TeRH@oI  
bFirst = false; 4Z.Dz@.c(  
read_nPos(); aGNb  Cm  
} *$Y_ %}  
else #'dNSez5  
{ ]Z?jo#F  
nStartPos = new long[bean.getNSplitter()]; .z[#j]k  
nEndPos = new long[bean.getNSplitter()]; S!66t?vHB  
} E V@yJ]  
I,W `s  
dkg| kw'  
'| p"HbJ  
} L~Y^O`c  
jo' V.]\  
 o .*t  
public void run() Je4hQJ<h  
{ o .( Gja4  
//获得文件长度 ; )FmN[  
//分割文件 tyFsnc k  
//实例FileSplitterFetch 4%#q.qI  
//启动FileSplitterFetch线程 c#-*]6x  
//等待子线程返回 &H[7UyC  
try{ QXW> }GdKZ  
if(bFirst) qOv`&%txW  
{ >X xHp  
nFileLength = getFileSize(); @r=,: 'Mt  
if(nFileLength == -1) '<$*N  
{ :7~DiH:Q  
System.err.println("File Length is not known!"); 1zgM$p  
} ;3XOk+  
else if(nFileLength == -2) 6)c-s|#  
{ {YG qa$+\  
System.err.println("File is not access!"); p'A43  
} wLzV#8>  
else "U/yq  
{ Nw{Cu+AwG  
for(int i=0;i<nStartPos.length;i++) iJ`zWpj+{Q  
{ />wE[`  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); gC(@]%  
} L;WFHIE  
for(int i=0;i<nEndPos.length-1;i++) 0BH-kr  
{ (/FG#D.  
nEndPos = nStartPos[i+1]; ZW4$Ks2]Y  
} h>F"GR?U_(  
nEndPos[nEndPos.length-1] = nFileLength; q4v:s   
} 5O;D\M{>  
} ;iW>i8  
M%WO  
j2%fAs<  
//启动子线程 a"`> J!  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; WL?qulC}h1  
for(int i=0;i<nStartPos.length;i++) }0?XF/e(R  
{ Shv$"x:W  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), OZA^L;#>  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Ww"]3  
nStartPos,nEndPos,i); qeb}~FL"o  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); C-\3,  
fileSplitterFetch.start(); xIwILY|W=  
} O`5hj q#  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), \ AIFIy  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1);  /PTq.  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", [N#4H3GM8  
nEndPos = " + nFileLength); Km,%p@`m  
// fileSplitterFetch[nPos.length-1].start(); q0DRT4K  
[RY Rt/?Q  
J=&}$  
//等待子线程结束 |*DkriYY  
//int count = 0; -{q'Tmst  
//是否结束while循环 upZ tVdd  
boolean breakWhile = false; FmhAUe  
v!$:t<-5N  
mT #A?C2  
while(!bStop) E]}_hZU  
{ t1G__5wp  
write_nPos(); M| Nh(kvH  
Utility.sleep(500); nSRNd A  
breakWhile = true; |o+*Iy)  
b 0qA  
2j#Dwa(lZQ  
for(int i=0;i<nStartPos.length;i++) U#&+n-npO  
{ o/Q|R+yXV  
if(!fileSplitterFetch.bDownOver) " %qr*|  
{ $E.Fgy:G  
breakWhile = false; D)Ep!`Q   
break; )U7fPKQ  
} 1wm`a  
} ^!x! F  
if(breakWhile) 81C;D`!K  
break; M6bM`wHH>  
'1(6@5tyWk  
mHV{9J  
//count++; Ql%B=vgKL  
//if(count>4) UNK.39  
// siteStop(); Nukyvse  
} V]GF53D  
^tjw }sE  
! ,{zDMA  
System.err.println("文件下载结束!"); S^;;\0#NK  
} ~$C}?y^ a  
catch(Exception e){e.printStackTrace ();} !Z 0U_*&  
} kDXQpe  
,i Y:#E  
;9~ WB X"  
//获得文件长度 pwkTe  
public long getFileSize() \<\H1;=.@'  
{ &]GR*a  
int nFileLength = -1; *X{7m]5  
try{ IsShAi  
URL url = new URL(siteInfoBean.getSSiteURL()); 8};kNW^2m  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); KVr9kcs  
httpConnection.setRequestProperty("User-Agent","NetFox"); GzBPI'C  
,k=8|=aF  
seRf q&  
int responseCode=httpConnection.getResponseCode(); /.=aA~|  
if(responseCode>=400) CBF<53TshR  
{ lSlZ^.&  
processErrorCode(responseCode); QnP?j&  
return -2; //-2 represent access is error G+Bk!o  
} znSlSQpTv  
I$p1^8~L  
<QO1Yg7}  
String sHeader; 0kNKt(_  
REYvFx?i  
;obOr~Jx'5  
for(int i=1;;i++) d7mn(= &  
{ }2;iIw`  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); <:NahxIlu  
//Utility.log(in.readLine()); B-$?5Ft!  
sHeader=httpConnection.getHeaderFieldKey(i); vm{8x o  
if(sHeader!=null) +2}cR66%  
{ [ZC\8tP`V  
if(sHeader.equals("Content-Length")) 93:oXyFjD  
{ 9#m3<oSJ  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); #/jug[wf*!  
break; X d o\DQn  
} ?Z_T3/ f  
} Kh[l};/F  
else F\^8k/0  
break; SDV#p];u  
} LMx/0  
} $v[mIR  
catch(IOException e){e.printStackTrace ();} 3;VH'hh_  
catch(Exception e){e.printStackTrace ();} %p$XK(6  
vd(S&&]o1  
_p5#`-%mM  
Utility.log(nFileLength); dP(.l}O  
/d,u"_=l  
~*"ZF-c,  
return nFileLength; C:}1r  
} HA,8O [jon  
RgUQ:  
t72u%M6  
//保存下载信息(文件指针位置) eY'n S  
private void write_nPos() KvEv0L<ky  
{ 7s3=Fa:9Q  
try{ iw=e"6V  
output = new DataOutputStream(new FileOutputStream(tmpFile)); sNcU>qjj6  
output.writeInt(nStartPos.length); @eeI4Jz  
for(int i=0;i<nStartPos.length;i++) U,Uy0s2r  
{ od5nRb  
// output.writeLong(nPos); m;\nMdn  
output.writeLong(fileSplitterFetch.nStartPos); jf`w8*R  
output.writeLong(fileSplitterFetch.nEndPos); =}kISh  
} mXyN{`q=  
output.close(); 4w=v /WDo  
} fM7B<eB  
catch(IOException e){e.printStackTrace ();} sve} ent  
catch(Exception e){e.printStackTrace ();} h@\-]zN{  
} {:*G/*1[.  
m_CW Vw  
?bt;i>O\  
//读取保存的下载信息(文件指针位置) 88,hza`#V  
private void read_nPos() 7)5G 1  
{ _ h5d~  
try{ w8R7Ksn(  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); gd]S;<Jh  
int nCount = input.readInt(); HcJ!(  
nStartPos = new long[nCount]; o$l8"Uv  
nEndPos = new long[nCount]; pfHjs3A=  
for(int i=0;i<nStartPos.length;i++) egSs=\  
{ L.yM"  
nStartPos = input.readLong(); UPr& `kaJ  
nEndPos = input.readLong(); d~rA`!s7`  
} &9)/"  
input.close(); v%AepK&  
} 5,s@K>9l;  
catch(IOException e){e.printStackTrace ();} F-rhxJd  
catch(Exception e){e.printStackTrace ();} "yh2+97l  
} /g!ZU2&l  
xvl{o  
#n{4f1TZ  
private void processErrorCode(int nErrorCode) .\T!oSb4[  
{ W_E^+Wl@  
System.err.println("Error Code : " + nErrorCode); l0`bseN <  
} 0m]QQGvJ{  
m//aAxmB  
NJgu`@YoI  
//停止文件下载 h&CZN !  
public void siteStop() 2ua!<^,  
{ 7yT/t1)  
bStop = true; fh3uo\`@  
for(int i=0;i<nStartPos.length;i++) XPqGv=CN  
fileSplitterFetch.splitterStop(); L(K 5f7\  
R&;x_4dr^  
5I1YB+$}e  
} nRB3VsL  
} ;22?-F^  
//负责部分文件的抓取 3IQI={:k|D  
**FileSplitterFetch.java }xt^}:D  
*/ ?!U.o1  
package NetFox; s|A[HQUtJ  
}q]*aADe  
}A@:JR+|  
import java.io.*; *cCx]C.~  
import java.net.*; j3;W-c`5  
i 0/QfB%O  
gBh X=2%  
public class FileSplitterFetch extends Thread { zJW2F_  
L~{(9J'(  
MXfyj5K  
String sURL; //File URL ;lb  
long nStartPos; //File Snippet Start Position PNo:[9`S;m  
long nEndPos; //File Snippet End Position ]?H12xz  
int nThreadID; //Thread's ID 0C%IdV%CU  
boolean bDownOver = false; //Downing is over lSaX!${R'T  
boolean bStop = false; //Stop identical RHn3\N  
FileAccessI fileAccessI = null; //File Access interface *(1 <J2j  
-*KKrte  
LYL_Ah'=  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException XZ]ji9'  
{ [pEb`s  
this.sURL = sURL; ()Kaxcs?+  
this.nStartPos = nStart; `r-Jy{!y4  
this.nEndPos = nEnd; v JGH8$%;,  
nThreadID = id; /huh}&NNu  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 FCEmg0qdjD  
} C F','gPnc  
N8At N\e  
IMbF]6%p(  
public void run() aY? VP?BL  
{ D!Y@Og.  
while(nStartPos < nEndPos && !bStop) ?M&@# lbG  
{ >Rt:8uurAG  
\9OKf|#j  
\RR` F .7  
try{ BWxJ1ENM  
URL url = new URL(sURL); "1^tVw|  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); f!yl&ulKU  
httpConnection.setRequestProperty("User-Agent","NetFox"); 5j.@)XXe  
String sProperty = "bytes="+nStartPos+"-"; WHBGhU  
httpConnection.setRequestProperty("RANGE",sProperty); X9|*`h<  
Utility.log(sProperty); X)hpbHa  
O&aD]~|  
 rn( drG  
InputStream input = httpConnection.getInputStream(); 4[x` \  
//logResponseHead(httpConnection); \ [OB.  
8%u|[Si;  
$`7Fk%#+e  
byte[] b = new byte[1024]; ysK J=  
int nRead; DFQ`(1Q  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) <";1[A%7<  
{ YYFS ({  
nStartPos += fileAccessI.write(b,0,nRead); \^9n&MonM  
//if(nThreadID == 1) ]zyT_}&  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); AN:s%w2  
} "IQYy~ /  
>SvS(N{  
IoJI|lP  
Utility.log("Thread " + nThreadID + " is over!"); O>h h  
bDownOver = true; 0lniu=xmQ-  
//nPos = fileAccessI.write (b,0,nRead); 8g)$%Fy+N  
} C}<e3BXc  
catch(Exception e){e.printStackTrace ();} D=z="p\  
} ]!sCWR  
} $mKExW  
]!^wB 3j  
"@ ^<~bw  
//打印回应的头信息 -QJ8\/1>  
public void logResponseHead(HttpURLConnection con) NY<qoV  
{ ktynIN  
for(int i=1;;i++) ca3zY|Oo  
{ BaI-ve  
String header=con.getHeaderFieldKey(i); 3GKKC9C6  
if(header!=null) k3t]lG p  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); Ih.)iTs~%  
Utility.log(header+" : "+con.getHeaderField(header)); bcwb'D\a  
else :TP4f ?FA  
break; +{=U!}3|  
} A9@coP5  
} zL}`7*d:v  
PPV T2;9  
*2-b&PQR{  
public void splitterStop() {ixKc  
{ _u6N aB  
bStop = true; Q%q;=a  
} hG~.Sc:G  
-a>CF^tH  
LNR1YC1c  
} ltk ARc3  
;Dp*.YJ  
<m~8pM  
/* <5j%!6zo  
**FileAccess.java }jC^&%|  
*//文件访问(定位,写) E A55!  
package NetFox; 0[d*Z  
import java.io.*; X=f%!  
XY6Sm{  
=&k[qqxg  
public class FileAccessI implements Serializable{ 9pj6`5Zn@6  
u@:[ dbJ  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 K@2"n| S;  
RandomAccessFile oSavedFile; Z-4/xi7  
long nPos; zmD7]?|  
t+F_/_"B  
?MSwr_eZH  
public FileAccessI() throws IOException seAPVzWUU  
{ NQuqM`LSQ  
this("",0); `_1fa7,z  
} x%H,ta%  
|BhL.  
p>J@"?%^  
public FileAccessI(String sName,long nPos) throws IOException  9S9j  
{ YW~ 9N  
oSavedFile = new RandomAccessFile(sName,"rw"); N<4 nb  
this.nPos = nPos; Dpu?JF]  
oSavedFile.seek(nPos); 1'p=yHw  
} *'H\`@L  
m*B4a9 f  
>0iCQKq  
public synchronized int write(byte[] b,int nStart,int nLen) #b)`as?!1  
{ |N6.:K[`  
int n = -1; K% snE7X?)  
try{ \Ezcr=0z{j  
oSavedFile.write(b,nStart,nLen); 3rHn?  
n = nLen; ' e!WZvr  
} M6A0D+08  
catch(IOException e) BUsxgs"),  
{ iyR"O1]  
e.printStackTrace (); 9dAtQwGR"6  
} `S-%}eUv  
{"$ [MYi:  
CGK]i. N  
return n; M,kO7g  
} $.w$x1  
C,mfA%63  
OJA_OqVp$K  
} ojm IEzsz  
3HcduJntl  
noz1W ]  
/* 0:I<TJ~P  
**SiteInfoBean.java #ucb  
*/ \I}EWI  
package NetFox; ^ZS!1%1  
@x!+_z  
0k5uqGLXe  
public class SiteInfoBean { k$f2i,7'  
(dyY@={q  
+hispU3ia  
private String sSiteURL; //Site's URL OXKV6r6f  
private String sFilePath; //Saved File's Path d)Z&_v<|  
private String sFileName; //Saved File's Name o+XQMg  
private int nSplitter; //Count of Splited Downloading File +rSU  
OR $i,N|  
ue+{djz[4  
public SiteInfoBean() z>y# ^f)r  
{//nSplitter的缺省值为5 #l- 0$  
//default value of nSplitter is 5 0J466H_d{  
this("","","",5); S#yGqN0i  
} a%kvC#B  
,g0t&jITo  
/uR/,R++  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 1 \aTA,  
{ [S~Bt78d%r  
sSiteURL= sURL; 1/;E8{  
sFilePath = sPath; ;34p [RT  
sFileName = sName; ;P;c!}:\b  
this.nSplitter = nSpiltter; :qB|~"9O  
R6;#+ 1D  
?GhMGpd Mq  
} ?D)$O CS  
Dyo^O=0c  
E6O!e<ze^  
public String getSSiteURL() O8" t.W  
{ o%;ly  
return sSiteURL; ~a_X 7  
} n=$ne2/  
.<fdX()e,  
Q}<QE:-&E  
public void setSSiteURL(String value) yVGf[ ~X  
{ <Ist^ h+o  
sSiteURL = value; a 8Xwz@ M  
} 1(>2tEjYT  
;;Z'd@  
Dic|n@_Fy  
public String getSFilePath() HYT~AO-!  
{ $- %um  
return sFilePath; EN/t5d  
} dy5}Jn%L  
$YY{|8@kjv  
4<E <sD  
public void setSFilePath(String value) m`q&[:  
{ ew dTsgt'  
sFilePath = value; m0h,!  
} 52#6uBe  
m2l9([u=^  
LA 2/<:  
public String getSFileName() &hL2xx=  
{ 4J(-~  
return sFileName; Q/4ICgo4  
} &)||~  
cqs.[0 z#B  
7 wEv`5  
public void setSFileName(String value) puWMgvv  
{ 6~W@$SP,F  
sFileName = value; ~@-r  
} ybFxz  
, u%V%  
<pHm=q/U  
public int getNSplitter() >!']w{G  
{ z^&$6c_  
return nSplitter; Tl[*(| /C  
} f#GMJ mCQs  
|%F4`gz8KP  
7D:rq 8$\  
public void setNSplitter(int nCount) C^B$_?  
{ +0Q +0:  
nSplitter = nCount; vbtZ5Gm  
} oCI\yp@a  
} ,5}w]6bCr  
|Z2"pV  
#Cu$y8~as  
/* q%$p56\?3  
**Utility.java #Y'b?&b  
*/ hqjjd-S0  
package NetFox; )b2O!p  
tAJ}36 aG  
q<z8P;oP^  
public class Utility { +5Dc5Bl  
Y0EX{oxt1  
a L+>XN  
public Utility() 5*YvgB;  
{ em0Y'J  
\**j \m   
!yrh50tD  
} A]i!131{w|  
u SQ#Y^V_  
//线程睡眠 #\D 74$D  
public static void sleep(int nSecond) [Eu) ~J*  
{ p0zC(v0*  
try{ LK}FI* A_  
Thread.sleep(nSecond); vo*oCfm  
} 6XU p$Pd(  
catch(Exception e) BU??}{  
{ s>L.V2!$0  
e.printStackTrace (); 7t<MHdw  
} h| wdx(4  
} eh]sye KBj  
.lP',hn  
//日志 VWHpfm[r%  
public static void log(String sMsg) UdnRsp9S  
{ q jc4IW t~  
System.err.println(sMsg); C f d* Q  
} ~AX~z)  
6z6\xkr  
pXN'vP  
public static void log(int sMsg) ?H@<8Ra=3  
{ s9nPxC&A  
System.err.println(sMsg); p!uB8F  
} {R@V  
} Lkx~>U   
)qbkKCq/FB  
~v pIy-  
/* (Ll'j0]k>  
**TestMethod.java  @,k5T51m  
*/ U1) Zh-aR  
package NetFox; (y.N-I,  
+BL46 Bq  
X"_ ^^d-  
public class TestMethod { sHk>ek]2I  
  P3|s}&  
0!lWxS0#=  
public TestMethod() !Pnjr T  
{ ///xx/weblogic60b2_win.exe ! {G0'   
try{ l}VE8-XB  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ^4"AWps  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Q]N&^ E  
SiteFileFetch fileFetch = new SiteFileFetch(bean); =|IlORf<  
fileFetch.start(); [{u3g4`}  
} v7./u4S|V  
catch(Exception e){e.printStackTrace ();} v]F4o1ckk  
t4v'X}7q]  
Q#SQ@oUzD  
} v=lW5%r,'  
!1=OaOT  
!f52JQyh  
public static void main(String[] args) 2 Kjd!~Z$  
{ ;2 &"  
new TestMethod(); breF,d$  
} LAf#Rco4  
} O=}Rp 1  
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