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
  • 10042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
/* 155vY  
**SiteFileFetch.java H_vGa!_  
*/ F\Q X=n  
package NetFox; L&LAh&%{2  
import java.io.*; w:HRzU>  
import java.net.*; r$WBEt,B  
kkU#0p?7  
<s wfYT!N  
public class SiteFileFetch extends Thread { tYUg%2G  
vp&N)t_  
_h^er+d!_  
SiteInfoBean siteInfoBean = null; //文件信息Bean 5iZx -M  
long[] nStartPos; //开始位置 ln*jakRrC  
long[] nEndPos; //结束位置 Ge^(Ag}vE  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 s0\}Q=s[  
long nFileLength; //文件长度 ;|r<mT/,  
boolean bFirst = true; //是否第一次取文件 *6/OLAkyF  
boolean bStop = false; //停止标志 c@|f'V4  
File tmpFile; //文件下载的临时信息 BG^)?_69  
DataOutputStream output; //输出到文件的输出流 /C6$B)w_*{  
6(8zt"E  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) ]QSQr *  
public SiteFileFetch(SiteInfoBean bean) throws IOException #7Jvk_r9Y  
{ r<OqI*7  
siteInfoBean = bean; +HkEbR'G0  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); -58Sb"f  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); 5b$QXO  
if(tmpFile.exists ()) q_86nvB<  
{ AYsiaSTRqW  
bFirst = false; yF@72tK  
read_nPos(); $J9/AFzO"  
} ;MH_pE/m  
else r*f:%epB%  
{ ^KUM4. 6  
nStartPos = new long[bean.getNSplitter()]; -GZ:}<W 6+  
nEndPos = new long[bean.getNSplitter()]; <tgfbY^nL  
} O &}`R5Y;  
n'9&q]GN|  
siz:YRur  
3U4h>T@s|  
} FV\$M6 _  
Fd/Ra]@\Y  
lS |:4U.  
public void run() iD) P6"  
{ S.|%dz  
//获得文件长度 y\XWg`X y  
//分割文件 1EQLsg`d^  
//实例FileSplitterFetch {)wl`mw3  
//启动FileSplitterFetch线程 6ANA oWg*  
//等待子线程返回 [/Xc},HbMe  
try{ !~`aEF3  
if(bFirst) QRHM#v S  
{ T854}RX[{  
nFileLength = getFileSize(); sWFw[ Y>  
if(nFileLength == -1) j"9Zaq_  
{ 5"z~BE7  
System.err.println("File Length is not known!"); ,~>u<Wc!S  
} d(F4-kBd  
else if(nFileLength == -2) AH|'{  
{ g-<[* nF  
System.err.println("File is not access!"); 3Gt@Fo=  
} u"-."_  
else 3Y=uBl  
{ )TOKHN  
for(int i=0;i<nStartPos.length;i++) J<-2dvq  
{ q],/%W  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); S#l)|c_~  
} xPMX\aI|l  
for(int i=0;i<nEndPos.length-1;i++) 3yu,qb'"&  
{ #Ti5G"C  
nEndPos = nStartPos[i+1]; /Y8{?  
} v<E_n;@9k  
nEndPos[nEndPos.length-1] = nFileLength; vg\fBHzn  
} 5](,N^u{):  
} LEA^o"NW.  
3$P GLM  
<^"0A  
//启动子线程 N[wyi&m4  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; w%eEj.MI|i  
for(int i=0;i<nStartPos.length;i++) VV"1IR  
{ 28O3N;a  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M4K>/-9X+V  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), z6'l" D'h  
nStartPos,nEndPos,i); 79}Qj7  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); >:P-3#e*  
fileSplitterFetch.start(); 2fG[q3`  
} "2GssBa  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), {%QWv%|  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); vf?m-wh  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 7F8>w 7Y]  
nEndPos = " + nFileLength); GtkZ%<KF9  
// fileSplitterFetch[nPos.length-1].start(); V?4G~~F  
T9]:, z  
J(kC  
//等待子线程结束 *.zC9Y,  
//int count = 0; &u0on) E  
//是否结束while循环 E\XD~  
boolean breakWhile = false; H)NT2@%{P  
v}&J*}_XZ  
ci`N ,&:R  
while(!bStop)  S/Gy:GIf  
{ c'Zs2s7$  
write_nPos(); 8~vE  
Utility.sleep(500); $GX9-^og=T  
breakWhile = true; D]hwG0Chd  
~%u;lr  
%$zX a%A  
for(int i=0;i<nStartPos.length;i++) zzZ K S  
{ Fo GSCg%  
if(!fileSplitterFetch.bDownOver) 6" |+\  
{ z?Qt%1q  
breakWhile = false;  ui1h M  
break; pR7D3Q:^7  
} Hb@PQcj  
} _A=Pr _kN  
if(breakWhile) 8% `Jf`  
break; <jtu/U]78|  
6"_ytqw7  
;p/$9b.0:  
//count++; LABLT;c  
//if(count>4) dS~#Lzm  
// siteStop(); zM++ Z*  
} }XIUz|  
Oo8"s+G  
1|3{.Ed  
System.err.println("文件下载结束!"); m7NrS?7  
} SMbhJ}\O  
catch(Exception e){e.printStackTrace ();} ql%]t~HR0  
} 4 X6_p(  
uz[5h0c  
QOKE9R#Y  
//获得文件长度 D7OPFN 7`  
public long getFileSize() yZqX[U  
{ Ah1fcXED  
int nFileLength = -1; S_Ug=8r4  
try{ +G lb  
URL url = new URL(siteInfoBean.getSSiteURL()); (}&O)3)  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); [Z{0|NR  
httpConnection.setRequestProperty("User-Agent","NetFox"); 0Nq6>^ %  
KImazS^  
f)%8*B  
int responseCode=httpConnection.getResponseCode(); wEMg~Hh  
if(responseCode>=400) -KFozwr5/  
{ @#KZ2^  
processErrorCode(responseCode); ^{w]r5d  
return -2; //-2 represent access is error E>3(ff&  
} \KT}T  
q8P$Md-=b1  
&kNJ s{  
String sHeader; j3)fmlA  
J:JkX>n%k=  
N!W2O>VS  
for(int i=1;;i++) $ru()/pI)z  
{ K!BS?n;  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 3F|#nq  
//Utility.log(in.readLine()); cuW&X9\m,  
sHeader=httpConnection.getHeaderFieldKey(i); ~ (/OB w  
if(sHeader!=null) i\z,)xp  
{ (_$'e%G0  
if(sHeader.equals("Content-Length")) 0N(o)WRv  
{ 13KfI  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); =TG[isC/F9  
break; <u%&@G$F>  
} f hS4Gb_  
} T\Ld)'fNv  
else {e'V^l.v  
break; uDXRw*rTv  
} \>@QJ  
} eod-N}o  
catch(IOException e){e.printStackTrace ();} }:2GD0Ru  
catch(Exception e){e.printStackTrace ();} ` $N()P  
FyV)Nmc%t  
(viGL|Ogn  
Utility.log(nFileLength); / >q?H)6  
F.[E;gOTo  
(h3f$  
return nFileLength; Oj~4uT&"  
} y m~  
_cw~N p  
EiP#xjn?c  
//保存下载信息(文件指针位置) [@LA<Z_  
private void write_nPos() {i09e1  
{ 8M&q  
try{ v62M8r,Y  
output = new DataOutputStream(new FileOutputStream(tmpFile)); { *&Wc Os  
output.writeInt(nStartPos.length); O h{ >xg  
for(int i=0;i<nStartPos.length;i++) 1U(P0$C  
{ #Z)8,N  
// output.writeLong(nPos); ^vA"3Ixb!  
output.writeLong(fileSplitterFetch.nStartPos); N&]GP l0  
output.writeLong(fileSplitterFetch.nEndPos); B !}/4"  
} u{+z?N  
output.close(); ,/uVq G  
} BhcTPQsW  
catch(IOException e){e.printStackTrace ();} R@[gkj  
catch(Exception e){e.printStackTrace ();} #o/  
} %{*A@jQsg  
<bbC &O\  
9J $"Qt5;6  
//读取保存的下载信息(文件指针位置) Uxl7O4J@H  
private void read_nPos() } S,KUH.  
{ 3 J!J#  
try{ a2!;$B%  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); bnYd19>  
int nCount = input.readInt(); |h6u%t2AY  
nStartPos = new long[nCount]; *@(j'0hj  
nEndPos = new long[nCount]; XQhbH^  
for(int i=0;i<nStartPos.length;i++) X<*-d6?gD`  
{ W~i599!v  
nStartPos = input.readLong(); |[B JZ  
nEndPos = input.readLong(); T5gL  
} Rxfhk,I  
input.close(); j+6`nN7L  
} 8[\ ~}Q6  
catch(IOException e){e.printStackTrace ();} kx.8VUoM V  
catch(Exception e){e.printStackTrace ();} ]r\d 5  
} fUV;3du  
W0qn$H  
`vc?*"  
private void processErrorCode(int nErrorCode) >= VCKN2'j  
{ p/WE[8U  
System.err.println("Error Code : " + nErrorCode); UJ^MS4;I3  
} 3Q\k!$zq  
_p^&]eQ+k#  
2Cgq&\wS  
//停止文件下载 ul!e!^qwx  
public void siteStop() og)f?4  
{ oa q!<lI  
bStop = true; $s,Az_bs  
for(int i=0;i<nStartPos.length;i++) l1uv]t <  
fileSplitterFetch.splitterStop(); c)B <d#  
mVVL[z2+  
8d|#W  
} K^f&+`v6_  
} trm-&e7q?;  
//负责部分文件的抓取 y??^[ sB  
**FileSplitterFetch.java gWLhO|y  
*/ ToE^%J4  
package NetFox; DR c-L$bD  
ywkyxt  
sB+ B,DF  
import java.io.*; \_|g}&}6Y  
import java.net.*; D9/PVd&#  
 Ds@nuQ  
M'>8P6O  
public class FileSplitterFetch extends Thread { L/*K4xQ  
a"bael  
j~C-T%kYa  
String sURL; //File URL XZH\HK)K-]  
long nStartPos; //File Snippet Start Position &{z RuF  
long nEndPos; //File Snippet End Position rfH Az  
int nThreadID; //Thread's ID I|/\L|vo  
boolean bDownOver = false; //Downing is over @0&KM|+  
boolean bStop = false; //Stop identical 56 [+;*  
FileAccessI fileAccessI = null; //File Access interface /j$`Cq3I  
y@2$sK3K  
q:vc ;y  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException >))K%\p   
{ F*J@OY8i  
this.sURL = sURL; mr<camL5  
this.nStartPos = nStart; {No Y`j5S  
this.nEndPos = nEnd; 'Fr"96C$  
nThreadID = id; X|Rw;FY  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 pWOK~=t  
} n1PV/ Z  
AZf$XHP2  
Y wu > k  
public void run() aM!%EaT  
{ .)[0yW&  
while(nStartPos < nEndPos && !bStop) 0.z\YTZ9  
{ D V=xqC6}  
N"-U)d-.  
s~g0VNu Y  
try{ {jOV8SVL  
URL url = new URL(sURL); =BroH\  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ..;ep2jSs  
httpConnection.setRequestProperty("User-Agent","NetFox"); 9six]T  
String sProperty = "bytes="+nStartPos+"-"; ~jDf,a2  
httpConnection.setRequestProperty("RANGE",sProperty); _ 0h)O  
Utility.log(sProperty); aU?HIIA  
Yc2dq e>  
?~=5 x  
InputStream input = httpConnection.getInputStream(); < gu>06  
//logResponseHead(httpConnection); ?4H>1Wkb  
"a=dx| Z  
Y^-D'2P]P  
byte[] b = new byte[1024]; |<!xD iB  
int nRead; E@CK.-N|  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ,lb >  
{ PsO>&Te2  
nStartPos += fileAccessI.write(b,0,nRead); cxpG6c  
//if(nThreadID == 1) (,;4f7\  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos);  >^J  
} bTc^ huP  
 >B$J  
n0%5mTUN  
Utility.log("Thread " + nThreadID + " is over!"); >?|c>HGX  
bDownOver = true; z6uHe{|  
//nPos = fileAccessI.write (b,0,nRead); tNC ;CP#R+  
} 4;V;8a\A  
catch(Exception e){e.printStackTrace ();} ;X%8I$Ba,  
} 4b  1a?  
} wOn*QO[  
1HBWOV7z.?  
DSL3+%KF#  
//打印回应的头信息 EFz Pt?l  
public void logResponseHead(HttpURLConnection con) tKY g  
{ S0H|:J  
for(int i=1;;i++) 9O|k|FD  
{ e`bP=7`0  
String header=con.getHeaderFieldKey(i); ()(^B}VK  
if(header!=null) U$ Od)  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); .tA=5 QY,  
Utility.log(header+" : "+con.getHeaderField(header)); C"R}_C|r)*  
else q]#j,}cN9  
break; :uB(PeAv*  
} ui<Mnm_T;d  
} #+(@i|!ifo  
=h,J!0Y  
bA\(oD+:  
public void splitterStop() $%.,=~W7  
{ VYnB&3 %DF  
bStop = true; rAh|r}R  
} +c' n,O~3  
349BQ5ND  
P1dFoQz  
} IubzHf  
TF~cDn  
0.0r?T  
/* (je`sV  
**FileAccess.java ZDx1v_xr  
*//文件访问(定位,写) cS(=wC  
package NetFox; FB2{qG3  
import java.io.*; *r|Zbxf(  
?G 'sb}.  
?^WX] SAl  
public class FileAccessI implements Serializable{ iHeu<3O  
tY%T  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 p<c1$O*  
RandomAccessFile oSavedFile; ;jh.\a_\  
long nPos; qAi:F=> X  
iz3Hoj  
 GjyTM  
public FileAccessI() throws IOException K6s tkDhb  
{ ? kCo/sW  
this("",0); #6mr'e1  
} 6\USeZh  
B/dJj#  
y(X^wC  
public FileAccessI(String sName,long nPos) throws IOException )!=fy']  
{ zQoJ8i>  
oSavedFile = new RandomAccessFile(sName,"rw"); ;i!$rL  
this.nPos = nPos; R0e!b+MZ.  
oSavedFile.seek(nPos); FTu<$`!1L  
} Sobp;OZ5  
3j2d&*0  
>N"=10  
public synchronized int write(byte[] b,int nStart,int nLen) 7>f)pfLM  
{ \jr-^n]  
int n = -1; jQ['f\R  
try{ {7.uwIW.1  
oSavedFile.write(b,nStart,nLen); 9Us'Q{CD   
n = nLen; !'Ww%ZL\   
} 1rV9dM#F  
catch(IOException e) |Elz{i-  
{ et<@3wyd]  
e.printStackTrace (); u. 2^t :A  
} '![VA8  
/w2NO9Q  
(zw.?ADPCT  
return n; U04)XfO;]  
} XsX];I{E,  
[6)vD@  
n<Ki.;-ZE  
} x$KQ*P~q  
3 <Zo{;  
A_+*b [P  
/* TIxlLOs  
**SiteInfoBean.java USH>`3  
*/ :Yn{:%p  
package NetFox; ~R7{gCqdr  
ceAefKdb  
A:*$rHbzl  
public class SiteInfoBean { [Vj|fy4  
r@ba1*y0  
&Q t1~#1  
private String sSiteURL; //Site's URL (, $Lp0mB7  
private String sFilePath; //Saved File's Path |T{ZDJ+  
private String sFileName; //Saved File's Name ^9XAWj"  
private int nSplitter; //Count of Splited Downloading File Ox6^=D "  
ZK8DziO  
@}{Fw;,(7n  
public SiteInfoBean() c[EG cY={  
{//nSplitter的缺省值为5 *2Q x69`  
//default value of nSplitter is 5 yn04[PN2  
this("","","",5); xI8v'[3  
} 2G$-:4B  
Q`UgtL  
]o`FF="at  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) vr$z6m ^  
{ #J%Fi).^)  
sSiteURL= sURL; o+?Ko=vYw  
sFilePath = sPath; ,62BZyT,T,  
sFileName = sName; h|ja67VG  
this.nSplitter = nSpiltter; D66!C{  
P> ~Lx  
I2C1mV  
} qb5IpI{U  
b<KKF'  
L'a>D  
public String getSSiteURL() F=yE>[! LB  
{ 2_){4+,fu  
return sSiteURL; op|x~Thf  
} ^7C,GaDsn  
2^&5D,}0  
yj9 Ad*.  
public void setSSiteURL(String value) T4}q%%7l  
{ VM"*@T  
sSiteURL = value; LY!.u?D`P  
} 5fK<DkB$>:  
:#UN^"(m}  
66cPoG  
public String getSFilePath() r-o6I:y  
{ \fL:Ie  
return sFilePath; *. ; }v@  
} RTTEAh:.  
el,n5O Z7  
RQ[6svfP  
public void setSFilePath(String value) D]d2opBLj  
{ }pv<<7}|  
sFilePath = value; ,y/N^^\  
} ~ph>?xuw  
z#sSLE.$Z  
tNCKL. yU  
public String getSFileName() l # F.S5i  
{ U+g<lgH1J  
return sFileName; 3/2G~$C  
} p\M\mK  
(+0yZ7AZ  
7(KVA1P66  
public void setSFileName(String value) >]WQ1E[=  
{ )rv<"  
sFileName = value; ^ZO3:"t!w  
} Sc&p*G  
NeY,Of|  
04R-}  
public int getNSplitter() \+sP<'~M  
{ k%lz%r  
return nSplitter; G G[$-  
} X.!|#FWb+  
XxE>KeP  
OAtn.LU  
public void setNSplitter(int nCount) p*(]8pDC  
{ SiSx ym  
nSplitter = nCount; kc70HrG  
} 7 {#^ zr  
} .(2ui~ed  
Md,KW#  
4 g^oy^~  
/* Ndr4e?Xa,  
**Utility.java mmrz:_  
*/ 8?&u5  
package NetFox; ?AJE*=b  
F^|4nBd*ub  
au 5qbP  
public class Utility { FrryZe=  
_m|Tr*i8  
G[5z3  
public Utility() vS'5Lm  
{ itW~2#nJz  
u|]`gsFZ\  
o2M4?}TpIV  
} o>Jr6: D(  
rfS kQT  
//线程睡眠 !o&b:7  
public static void sleep(int nSecond) F[ 5\ x0  
{ !c8hER!  
try{ !*l5%H  
Thread.sleep(nSecond); CERT`W%o  
} csay\Q{  
catch(Exception e) OwM.N+ z#T  
{ OJF41Z  
e.printStackTrace (); nJ-U*yz  
} KnuQ 5\y  
} h^$ c  
Xm! ;  
//日志 =Wj{J.7mf]  
public static void log(String sMsg)  rVo?I  
{ 5b^`M  
System.err.println(sMsg); fer~NlX  
} oCftI':@  
)2jBhT  
c={bunnz#  
public static void log(int sMsg) !DUC#)F  
{ Iq[Z5k(K  
System.err.println(sMsg); >1n[Y- r  
} cc^[ u+  
} ~'9>jpnw  
RIO4`,  
$M=W`E[g  
/* ZNEWUt{+;^  
**TestMethod.java u`2[V4=L  
*/ .\X;VWTI  
package NetFox; fmhqm"  
PV_q=70%T  
F};G&  
public class TestMethod { <) ` ?s  
BcvCm+.S:  
'sCj|=y2Qc  
public TestMethod() ZRd,V~iz  
{ ///xx/weblogic60b2_win.exe Y@Zv52,  
try{ &m>sGCZ  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 5/),HGxi  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); voHFU#Z$  
SiteFileFetch fileFetch = new SiteFileFetch(bean); WI$MT6  
fileFetch.start(); 1/H9(2{L  
} k7gm)}RKcu  
catch(Exception e){e.printStackTrace ();} ?Hd/!I&  
I;<aJo6Yl  
LT3ViCZ-n  
} 6HW8mXQh<h  
/bd1Bi  
#H@rb  
public static void main(String[] args) C;6Nu W  
{ @l:o0(!W  
new TestMethod(); 9"H]zfW  
} pUz;e#J|  
} ;L gxL Qy;  
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