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
  • 11890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
/* C`LHFqv  
**SiteFileFetch.java F vt5vQ  
*/ ;+-M+9"?O  
package NetFox; 9pJk.Np0   
import java.io.*; M8HHyV[AmC  
import java.net.*; "fTW2D74  
AV%t<fDG#  
/$NZj" #  
public class SiteFileFetch extends Thread { o+j~~P  
<+\ w.!  
/3pvq%i  
SiteInfoBean siteInfoBean = null; //文件信息Bean oYn|>`+6:y  
long[] nStartPos; //开始位置 py8)e7gX=  
long[] nEndPos; //结束位置 ZN `D!e6  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 9C_Vb39::$  
long nFileLength; //文件长度 ;#jE??E/:  
boolean bFirst = true; //是否第一次取文件 {i09e1  
boolean bStop = false; //停止标志 R%\K<#^\  
File tmpFile; //文件下载的临时信息 K[~fpQGbV1  
DataOutputStream output; //输出到文件的输出流 mv;;0xH  
-{ M(1vV(=  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) N& 683z  
public SiteFileFetch(SiteInfoBean bean) throws IOException 5U!yc7eBI/  
{ n?=d)[]  
siteInfoBean = bean; B{ptP4As-  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); VwKo)zH  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); rM y(NAo_  
if(tmpFile.exists ()) zs<2Ozv  
{ d=v{3*a_4,  
bFirst = false; =Mby;wQ?|  
read_nPos(); ;Or]x?-  
} q{:]D(   
else nhZ^`mP  
{ v3 q.,I_  
nStartPos = new long[bean.getNSplitter()]; j{?ogFfi  
nEndPos = new long[bean.getNSplitter()]; [W#M(`}D  
} : 3 aZ_  
R$Or&:E ^  
K#>@T<  
Y_SB3 $])  
} }Jr!a M'  
v:7_ZD6kR  
aViZKps`m  
public void run() (SnrY O`#  
{ kl0|22"Gz  
//获得文件长度 6myF!  H=  
//分割文件 (n+FEE<  
//实例FileSplitterFetch @3_[NI%  
//启动FileSplitterFetch线程 jMV9r-{*+  
//等待子线程返回 -Y=o  
try{ Qf:#{~/  
if(bFirst) 9iy3 dy^  
{ Q`{2 yU:r  
nFileLength = getFileSize(); c ?(X(FQ  
if(nFileLength == -1) |_GESpoHH  
{ fp`k1Uq@  
System.err.println("File Length is not known!"); XJI ff$K  
} h:3^FV&#  
else if(nFileLength == -2) :)eU)r"s4  
{ B65"jy  
System.err.println("File is not access!"); k`u.:C&  
} ObyF~j}j  
else ["65\GI?  
{ DbIn3/W Ne  
for(int i=0;i<nStartPos.length;i++) '] $mt  
{ 5dXDL~/2p  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); j : $Ruy  
} 4!k 0  
for(int i=0;i<nEndPos.length-1;i++) li7"{+ct  
{ L7rH=gZ&!]  
nEndPos = nStartPos[i+1]; l =Is-N`  
} ZtofDp5B  
nEndPos[nEndPos.length-1] = nFileLength; D%%@+3a  
} D]StDOmM  
} "t!_b ma  
"eb+O  
!bGMVw6_  
//启动子线程 __OH gp 1  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; *< ?~  
for(int i=0;i<nStartPos.length;i++) y|Vwy4tK9  
{ PC55A1(T  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), =`W#R  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), =f\BAi  
nStartPos,nEndPos,i); lV ra&5  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); p/WE[8U  
fileSplitterFetch.start(); N*NGC!p`N  
} yZyB.wT  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), oH>G3n|U^  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); _p^&]eQ+k#  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", agUdPl$e\  
nEndPos = " + nFileLength); .jK,6't^  
// fileSplitterFetch[nPos.length-1].start(); %SKJ#b  
og)f?4  
U3OXO 1  
//等待子线程结束 L[a A4`  
//int count = 0; E~K5n2CI  
//是否结束while循环 f C_H0h3  
boolean breakWhile = false; H5X.CcI&}  
r t\eze_5A  
"Iu Pg=|#  
while(!bStop) 8d|#W  
{ +txHj(Y`  
write_nPos(); U%u%_{-  
Utility.sleep(500); Fsi;[be$A  
breakWhile = true; D wtvtglqV  
q2}6lf,J K  
[Zj6v a  
for(int i=0;i<nStartPos.length;i++) ^nGKuW7\  
{ Z.E@aml\  
if(!fileSplitterFetch.bDownOver) =?oYEO7  
{ 3`U^sr:[%  
breakWhile = false; }]!?t~5*  
break; :vo#(  
} kB3@;z:  
} O&@pi-=o  
if(breakWhile) ay`A Gr  
break; .0b4"0~T6  
? e<D +  
rcU*6`IWA  
//count++; ''3b[<  
//if(count>4) dk[MT'DV  
// siteStop(); aYrbB#  
} 6)j/"9oY  
qfS ]vc_N  
;tG@ 6  
System.err.println("文件下载结束!"); I6lWB(H!u  
} n1r'Y;G  
catch(Exception e){e.printStackTrace ();} R!y`p:O C  
} ka?EXF:  
KbM1b  
u.9syr  
//获得文件长度 "*JyNwf  
public long getFileSize() i=AQ1X\s  
{ a*bAf'=  
int nFileLength = -1; Su*f`~G];  
try{ 6!$2nK+  
URL url = new URL(siteInfoBean.getSSiteURL()); >NMq^J'/  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Gm.2!F=R4A  
httpConnection.setRequestProperty("User-Agent","NetFox"); }y&tF'qG  
4B$|UG  
!63]t?QXMG  
int responseCode=httpConnection.getResponseCode(); bW?cb5C  
if(responseCode>=400) &E0L 2gbI  
{ Q1^kU0M}  
processErrorCode(responseCode); v)s; wD  
return -2; //-2 represent access is error Gzkvj:(V  
} cTu"Tu\Qw  
wNQhg  
*EllE+M{n  
String sHeader; r31)Ed$  
~tB#Q6`nB  
~d"9?K^#  
for(int i=1;;i++) kmur={IR  
{ @;`d\lQ  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); "U o~fJ  
//Utility.log(in.readLine()); BVe c  
sHeader=httpConnection.getHeaderFieldKey(i); Pt\GVWi_t  
if(sHeader!=null) HMl M!Xk?  
{ H}PZJf_E  
if(sHeader.equals("Content-Length")) lqZUU92;  
{ FfpP<(4  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); eiJ~1H X)  
break; {jOV8SVL  
} GFfZ TA  
} 3fd?xhWbN  
else 7;3;8Q FX  
break; $9rQ w1#e  
} D]NJ ^.X  
} k4+Q$3"  
catch(IOException e){e.printStackTrace ();} Ux+UcBKm-  
catch(Exception e){e.printStackTrace ();} 9 `T2  
qLa6c2o,  
Bh5z4  
Utility.log(nFileLength); 2f0qfF  
H J0Rcw%  
(Q F-=o  
return nFileLength; A# Ne07d  
} ?4H>1Wkb  
JN> h:  
h)pYV>!d  
//保存下载信息(文件指针位置) qt`HP3J&  
private void write_nPos() |<!xD iB  
{ iCNJ%AZ H  
try{ I~) A!vp  
output = new DataOutputStream(new FileOutputStream(tmpFile)); n# "N"6s  
output.writeInt(nStartPos.length); PsO>&Te2  
for(int i=0;i<nStartPos.length;i++) fX{Xw0  
{ e_3($pj  
// output.writeLong(nPos); 5#B M  
output.writeLong(fileSplitterFetch.nStartPos); Zr|z!S?aSC  
output.writeLong(fileSplitterFetch.nEndPos); &h'NC%"v  
} M~P h/  
output.close(); 5nS}h76mZ  
} H{ I,m-  
catch(IOException e){e.printStackTrace ();} Y[. f`Ei2  
catch(Exception e){e.printStackTrace ();} o|Kd\<rY  
} bA02)?L  
\%Lj !\  
@YHt[>*S  
//读取保存的下载信息(文件指针位置) DsCbMs=Y  
private void read_nPos() Mt\.?V:  
{ `9mc+  
try{ 3_N1y  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); k~IRds@G  
int nCount = input.readInt(); }dpE>  
nStartPos = new long[nCount]; 0s .X  
nEndPos = new long[nCount]; 1BOv|xPjZ  
for(int i=0;i<nStartPos.length;i++) EFz Pt?l  
{ 8)XAdAr  
nStartPos = input.readLong(); ,)PpE&  
nEndPos = input.readLong(); ;uN&yj<}a  
} Zy=DY  
input.close(); ]/{iIS_  
} V@pUU~6R  
catch(IOException e){e.printStackTrace ();} 0 LQ%tn  
catch(Exception e){e.printStackTrace ();} CS\8ej}y  
} )*nZ6Cg'  
{-1N@*K  
'H-hp   
private void processErrorCode(int nErrorCode) YYF.0G}  
{ 0S&C[I o6  
System.err.println("Error Code : " + nErrorCode); K96N{"{iI%  
} _3zJ.%  
Iwe  
i0'g$  
//停止文件下载 F!zGk(Pu  
public void siteStop() =k##*%  
{ {Lugdf'  
bStop = true; ?eDZ-u9)  
for(int i=0;i<nStartPos.length;i++) &EJ/Rl  
fileSplitterFetch.splitterStop(); 79Ur1-]/  
vf?Xt  
GsU.Lkf  
} bwe)_<c  
} 9v?rNJs  
//负责部分文件的抓取 =+w/t9I[  
**FileSplitterFetch.java " 1%\Fil  
*/ JQ9+kZ  
package NetFox; .$a|&P=S  
'RZ0,SK'  
cS(=wC  
import java.io.*; ?D['>Rzu  
import java.net.*; @nOuFX4  
2[i(XG{/  
(&Mv!6]  
public class FileSplitterFetch extends Thread { K)GpQ|4:<  
?^WX] SAl  
5V8`-yO9  
String sURL; //File URL cp2a @  
long nStartPos; //File Snippet Start Position *0x!C8*`Xe  
long nEndPos; //File Snippet End Position =55V<VI  
int nThreadID; //Thread's ID 2hY"bpGW   
boolean bDownOver = false; //Downing is over k_`YVsEYP  
boolean bStop = false; //Stop identical lw _@(E]E  
FileAccessI fileAccessI = null; //File Access interface aj]pN,g@N  
KN'twPFq  
\ 0.!al0  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 't+'rG6x  
{ =Y*zF>#lP  
this.sURL = sURL; 5h6-aQU[  
this.nStartPos = nStart; T[kS;-x  
this.nEndPos = nEnd; &"DD&87N%  
nThreadID = id; {Zo*FZcaX  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 g=jB'h?  
} '#lc?Y(pJ2  
pER[^LH_)  
MUUhg  
public void run() ?N]G;%3/  
{ W/.Wp|C}K3  
while(nStartPos < nEndPos && !bStop) 2/ejU,S  
{ |y&vMx~t  
y\Wp} }  
.t.4y. 97  
try{ ='6@^6y  
URL url = new URL(sURL); p~OX1RBI  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ?dmw z4k0  
httpConnection.setRequestProperty("User-Agent","NetFox"); n^` `)"  
String sProperty = "bytes="+nStartPos+"-"; #rQT)n  
httpConnection.setRequestProperty("RANGE",sProperty); \jr-^n]  
Utility.log(sProperty); #g~]2x  
zz #IY'dwT  
&?# YjU"  
InputStream input = httpConnection.getInputStream(); #>2cfZ`6'J  
//logResponseHead(httpConnection); JPpNCC.b  
\`W8#fob  
j43i:c;F  
byte[] b = new byte[1024]; rh T!8dTk  
int nRead; 74a k|(!  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) * yGlX[  
{ WnhH]WY  
nStartPos += fileAccessI.write(b,0,nRead); Rm Q>.?  
//if(nThreadID == 1) 2=$ F*B>9  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); )h1 `?q:5  
} (zw.?ADPCT  
rBZ00}  
vy5I#q(k  
Utility.log("Thread " + nThreadID + " is over!"); g{JH5IZ~  
bDownOver = true; [6)vD@  
//nPos = fileAccessI.write (b,0,nRead); V o%GO 9b;  
} = Q"(9[Az  
catch(Exception e){e.printStackTrace ();} O^IS:\JX&  
} 3 <Zo{;  
} -Fc 9mv(H  
D0yH2[j+  
rd^j<  
//打印回应的头信息 gF\ac%9  
public void logResponseHead(HttpURLConnection con) m Gx{Vpt  
{ 4MRN{W6  
for(int i=1;;i++) 0OBwe6*  
{ RQ,X0 pS  
String header=con.getHeaderFieldKey(i); qWJa p-hb  
if(header!=null) {'cdi`  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); :<uCi\9(  
Utility.log(header+" : "+con.getHeaderField(header)); LG'1^W{a  
else :|Bzbn=N2  
break; t![972.&  
} 1pT/`x  
} BR tT 7  
xLw[ aYy4  
eNrwkV^  
public void splitterStop() c+jnQM'  
{ i}>} %l|  
bStop = true; D!D}mPi[  
} 1~[GGl  
~e=KBYDBu  
S9 @*g3  
} 5K00z?kD2V  
M] W5 %3do  
'8b=4mrbH  
/* _#w5hX cu  
**FileAccess.java a]4|XJ_  
*//文件访问(定位,写) j2jUrl  
package NetFox; uKo4nXVtp  
import java.io.*; mWuhXY^Q  
D1EHT}  
U!T#'H5'-  
public class FileAccessI implements Serializable{ m^4Ojik  
Ps~)l#gue  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 kv`5"pa7M  
RandomAccessFile oSavedFile; +'UxO'v3]  
long nPos; t_Ul;HVPS  
+Q!Kj7EU/  
(ewcj\l4*  
public FileAccessI() throws IOException IXsOTBM  
{ 8\[qR_LV  
this("",0); _RX*Ps=  
} D66!C{  
jxnb<!|?H@  
tfjbG;R  
public FileAccessI(String sName,long nPos) throws IOException /P*ph0S-  
{ #M92=IH  
oSavedFile = new RandomAccessFile(sName,"rw"); D$SO 6X~  
this.nPos = nPos; 7/BA!V(na  
oSavedFile.seek(nPos);  DIh[%  
} -3C$br  
F-Ywl)  
CxVrnb[`q  
public synchronized int write(byte[] b,int nStart,int nLen) g'V,K\TG  
{ EZ^M?awB4  
int n = -1; 4'XCO+i#  
try{ &XSe&1  
oSavedFile.write(b,nStart,nLen); 0*o=JM]  
n = nLen; 'Y5=A!*@tf  
} 62#8c~ dL  
catch(IOException e) =4 W jb  
{ k? =_p6>  
e.printStackTrace (); G_?qY#"(  
} 'deqF|Iox  
cS"PIelR  
{1W,-%  
return n; %$F\o1S  
} sUsIu,1Q  
V _pKe~  
5@~5RNrq2  
} LU@+O12  
R= *vPS  
m`/!7wQs  
/* [ ]=}0l<J  
**SiteInfoBean.java U &y?3  
*/ 8wA'a'V.  
package NetFox; sg,9{R ^  
/ee4 v!  
5VW*h  
public class SiteInfoBean { cin3)lm  
CB?,[#r5f  
,T7(!)dR  
private String sSiteURL; //Site's URL L!kbDbqn  
private String sFilePath; //Saved File's Path mKBPIQ+ZS  
private String sFileName; //Saved File's Name 1PT0<C-  
private int nSplitter; //Count of Splited Downloading File kam \dn04  
on0>_-n)  
Y ptP_R:2p  
public SiteInfoBean() Z6oA>D  
{//nSplitter的缺省值为5 "_e /O&-cH  
//default value of nSplitter is 5 GZ/vUe  
this("","","",5); ?:sQ]S/Er  
} ^ZO3:"t!w  
`Yc>I!iN  
X !l#1  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 4gK_' b6"  
{ +jX.::UPm  
sSiteURL= sURL; l%$co07cX  
sFilePath = sPath; (Y]G6> Oa  
sFileName = sName; PQ[x A*  
this.nSplitter = nSpiltter; G G[$-  
MM4Eq>F/  
Hf$LWPL)lM  
} KmRxbf  
STgYXA(  
QsH Fk5)  
public String getSSiteURL() JD$;6Jv3P  
{ W=T,hOyh<W  
return sSiteURL; HCKj8-*  
} Oe}6jcb6&  
b n<}  
{V~G r  
public void setSSiteURL(String value) 5R7DD5c[  
{ $qj||zA  
sSiteURL = value; Md,KW#  
} *>p#/'_E  
# :3~I  
Ie8jBf -  
public String getSFilePath() fQOh%i9n5  
{ :i:M7}r  
return sFilePath; 4PAuEM/z  
} >D/+04w  
 6,;7iA]  
xBi``x2eY  
public void setSFilePath(String value) :0RfA%  
{ U49 `!~b7  
sFilePath = value; +cnBEv~y  
} 4I^8f||b_  
VCUEzR0  
sj0{;>>%+N  
public String getSFileName() 'w5g s}1D  
{ p8Wik<'^  
return sFileName;  MUd 9R  
} _ -/<bO  
vL"[7'  
fbK`A?5K  
public void setSFileName(String value) LdM9k(  
{ F[ 5\ x0  
sFileName = value; gT~Yn~~b  
} ;nB.f.e`  
@fxDe[J:  
 @Iy&Qo  
public int getNSplitter() )~l`%+  
{ @-QDp`QtI  
return nSplitter; y6S:[Z{~A  
} VaRP+J}UA.  
N/&t) 7  
41V}6+$g  
public void setNSplitter(int nCount) +Qe&#"O0  
{ '+ cPx\4  
nSplitter = nCount; :F`yAB3  
} -<tfbaA  
} N^{+1u7  
d]6#pSE  
U}Aoz|  
/* J_Pb R b  
**Utility.java b)Px  
*/ 60 z =bd]  
package NetFox;  <c &6M  
/ !*+9+h  
)2jBhT  
public class Utility { 9c_h+XN?y  
1v^eXvY  
\E<t'\>@X  
public Utility() [10;Mg  
{ UI>?"b6 L  
ZBAtRs  
3bW(VvgcL4  
} x#{.mN  
R2[-Q"|Ra  
//线程睡眠 z3:tSjF  
public static void sleep(int nSecond)  e ):rr*  
{ B:Xmc,|,  
try{ M'4$z^@Z  
Thread.sleep(nSecond); %!i|"FNc  
} EecV%E  
catch(Exception e) C{8d^SCA"  
{ }QqmDK.  
e.printStackTrace (); `fRp9o/  
} oG_-a(N  
} xiW;Y{kZ  
41[1_p(  
//日志 xrPC  
public static void log(String sMsg)  qg+bh  
{ p7pJ90~E  
System.err.println(sMsg); Y@Zv52,  
} cKKl\g@}  
lp;= f  
D!oELZ3  
public static void log(int sMsg) # ,KjJ  
{ 71# ipZ  
System.err.println(sMsg); Cd"iaiTD0  
} f2y:K6$'l*  
} xC,;IS k,  
d;$<K  
<+oTYPgD9  
/* e5 ?;{H  
**TestMethod.java TEK]$%2  
*/ eaxp(VX?oy  
package NetFox; [*k25N  
Iw<: k  
+W6QtB6  
public class TestMethod { ]E hW  
VkNg Vjg  
W_E0+  
public TestMethod() [0(+E2/:2  
{ ///xx/weblogic60b2_win.exe a\Ond#1p  
try{ d}.*hgk  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); c9eLNVM  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); kq SpZoV0'  
SiteFileFetch fileFetch = new SiteFileFetch(bean); 2C!Ko"1Y'  
fileFetch.start(); )lo;y~ o  
} 2V 1|b`b#4  
catch(Exception e){e.printStackTrace ();} }op0`-Xb  
}? W[D  
8a^E{x@HT  
} ,/=Fm  
 Nx8~Rn  
~P47:IZf  
public static void main(String[] args) i@C1}o-/  
{ Q3$AL@".  
new TestMethod(); ;ss,x  
} uq>\pO&P  
} ]d}U68$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
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