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
  • 9427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
/* q2$-U&  
**SiteFileFetch.java $ ]fautQlt  
*/ wU"0@^k]<  
package NetFox; k2-:! IE  
import java.io.*; FFG/v`NM  
import java.net.*; L[j73z'  
9 rMP"td  
<[oPh(!V  
public class SiteFileFetch extends Thread { 5z T~/6-(  
]Qu.-F#g  
"mk4O4dF  
SiteInfoBean siteInfoBean = null; //文件信息Bean tM% f#O  
long[] nStartPos; //开始位置 u@@0YUa  
long[] nEndPos; //结束位置 AZHZUd4  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 hoLQuh%2%  
long nFileLength; //文件长度  pxuZ=<  
boolean bFirst = true; //是否第一次取文件 YKWiZ  
boolean bStop = false; //停止标志 z{>p<)h  
File tmpFile; //文件下载的临时信息 9B&fEmgEc?  
DataOutputStream output; //输出到文件的输出流 W1$<,4j@M  
HCCEIgCT  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) + Cf  
public SiteFileFetch(SiteInfoBean bean) throws IOException lMQ_S"  
{ <*Ex6/j  
siteInfoBean = bean; |e%o  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); l>kREfHq!{  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); >l>;"R9N  
if(tmpFile.exists ()) =_"[ &^  
{ f Yt y7  
bFirst = false; D)_67w|u|  
read_nPos(); `\pv^#5HV9  
} 1 7..  
else <'N(`.&3C  
{ 4 g%BCGsys  
nStartPos = new long[bean.getNSplitter()]; kp$w)%2JW  
nEndPos = new long[bean.getNSplitter()]; &Q>tV+*  
} k^%Kw(/  
fqY; > Z  
^^;#Si  
9_4bw9 A  
} nYvx[ zq?^  
8M~^/Zc  
y$Y*%D^w  
public void run() ov9+6'zya  
{ VJf|r#2  
//获得文件长度 Uc[ @]  
//分割文件 !EuqJjh  
//实例FileSplitterFetch 8NUVHcB6  
//启动FileSplitterFetch线程 d41DcgG'j(  
//等待子线程返回 f~rq)2V:  
try{  W>HGB  
if(bFirst) 2C &G' @>  
{ AWG;G+  
nFileLength = getFileSize(); :|5 \XV)>  
if(nFileLength == -1) O^L#(8bC  
{ w y\0o  
System.err.println("File Length is not known!"); sx]kH$  
} ?nwFc3qw  
else if(nFileLength == -2) [#3*R_#8R  
{ Rt6(y #dF  
System.err.println("File is not access!"); x Ilo@W6  
} 1[ 4)Sq?  
else q; n  
{ d'okXCG  
for(int i=0;i<nStartPos.length;i++) gR]NH  
{ nF#1B4b>  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); aQTISX;  
} e6(Pw20)s  
for(int i=0;i<nEndPos.length-1;i++) K!cLEG!G  
{ b<]Ae!I'  
nEndPos = nStartPos[i+1]; zQ=c6xvm8  
} gd,3}@@SH  
nEndPos[nEndPos.length-1] = nFileLength; T!F0_<  
} YPU*T&~  
} N+3]C9 2o  
Y48MCL  
#86=[*Dr  
//启动子线程 >Hd0l L  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; >%?kp[  
for(int i=0;i<nStartPos.length;i++) .:U`4 ->E  
{ -V_iv/fmM  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), s-[v[w'E  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), <=g{E-  
nStartPos,nEndPos,i); |3:e$  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); NU <K+k  
fileSplitterFetch.start(); |}07tUq  
} {}A1[ Y|  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 'Y;M%  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); @,i_Gw)  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", U%?  
nEndPos = " + nFileLength); A{IJ](5.kd  
// fileSplitterFetch[nPos.length-1].start(); `J v~.EF%  
>[A7oH  
)b7;w#%q  
//等待子线程结束 ^K]`ZQjKC  
//int count = 0; ,'%wadOo  
//是否结束while循环 yOdh?:Imv  
boolean breakWhile = false; Zai:?%^  
O`rKxP  
Fo:60)Lr  
while(!bStop) }9FAM@x1K&  
{ dR|*VT\  
write_nPos(); >DSD1i+N  
Utility.sleep(500); )a=58r07  
breakWhile = true; L8WYxJ k  
Kwmtt  
J4l \  
for(int i=0;i<nStartPos.length;i++) ;+3XDz v  
{  nPRv.h  
if(!fileSplitterFetch.bDownOver) N7l`-y  
{ j-%@A`j;  
breakWhile = false; ,"xr^@W  
break; I8%Uyap{  
} \nbGdka  
} Tfow_t}\  
if(breakWhile) =Y]'wb  
break; Iss)7I  
e{6I-5`|,#  
9,J^tN@^  
//count++; Zjq(]y  
//if(count>4) q dQQt5Y'm  
// siteStop(); ur@"wcl"V  
} 8ZN"-]*  
Gzw9E.Hk  
2qgm(jo *y  
System.err.println("文件下载结束!"); 30fqD1_{  
} 7 /7,55  
catch(Exception e){e.printStackTrace ();} Pu0 <Clh  
} 3 [r9v!l  
O]cuJp  
y3Qb2l  
//获得文件长度 < pWk   
public long getFileSize() &$NYZ3?9  
{ <_>xkQbn2  
int nFileLength = -1; kb~;s-$O`s  
try{ CBKLct>  
URL url = new URL(siteInfoBean.getSSiteURL()); {7Qj+e^  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); B }t529Z  
httpConnection.setRequestProperty("User-Agent","NetFox"); yR$ld.[uf  
es!>u{8)  
k esuM3  
int responseCode=httpConnection.getResponseCode(); 6 qK`X  
if(responseCode>=400) ,k |QuOrCh  
{ M;j)F  
processErrorCode(responseCode); m'PU0x  
return -2; //-2 represent access is error y"T(Unvc  
} {g7~e {2  
(TTS-(  
T?k!%5,Kj  
String sHeader; qq '%9  
|7)oX  
)F'r-I%Hi  
for(int i=1;;i++) :um]a70  
{ Csf!I@}Z  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); wO&+Bb\=  
//Utility.log(in.readLine()); 36MNaQt'e  
sHeader=httpConnection.getHeaderFieldKey(i); %?m_;iv  
if(sHeader!=null) :y1,OR/k  
{ #5yz~&  
if(sHeader.equals("Content-Length")) HAmAmEc,  
{ FjV)QP H  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); V/Q/Ujgg  
break; ((AIrE>Rr  
} BF/l#)$yK  
} =:*2t  
else +5"Pm]oRbx  
break; N1yx|g:  
} $!7$0WbC  
} C$4!|Wg3  
catch(IOException e){e.printStackTrace ();} @ MKf$O4K  
catch(Exception e){e.printStackTrace ();} a)QSq<2*  
8 -YC#&  
!rTkH4!_  
Utility.log(nFileLength); })umg8s  
Vb,'VN%   
x(7Q5Uk\  
return nFileLength; td5! S]  
} Q" G;L  
Cg3 d  
8 k )i-&R  
//保存下载信息(文件指针位置) m[qW)N:w  
private void write_nPos() ;T :]?5W!  
{ 4u= v  
try{ Zg$RiQ^-{J  
output = new DataOutputStream(new FileOutputStream(tmpFile)); zALtG<_t  
output.writeInt(nStartPos.length); . "Q}2  
for(int i=0;i<nStartPos.length;i++) TjS &V  
{ 3(`P x}  
// output.writeLong(nPos); ]cM,m2^2  
output.writeLong(fileSplitterFetch.nStartPos); s)G?5Gz  
output.writeLong(fileSplitterFetch.nEndPos); 7O,!67+^~  
} d}<-G.&_  
output.close(); -5Oy k,  
} @?*; -]#)  
catch(IOException e){e.printStackTrace ();} e2kW,JV/<$  
catch(Exception e){e.printStackTrace ();} H'}6Mw%ra  
} ,olP}  
Y+{jG(rg.F  
*uoO#4g~  
//读取保存的下载信息(文件指针位置) oSLm?Lu  
private void read_nPos() $"ACg!=M  
{ QzxEkTc;  
try{ JnLF61   
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); sh*/wM  
int nCount = input.readInt(); $f=6>Kn|^]  
nStartPos = new long[nCount]; !oYNJE Y7  
nEndPos = new long[nCount]; L *cP8v4  
for(int i=0;i<nStartPos.length;i++) \_x~lRqJJ  
{ Nu euCiP  
nStartPos = input.readLong(); h@dy}Id  
nEndPos = input.readLong(); o4jh n[Fx  
} pKU(4&BxX  
input.close(); fr`Q 5!0  
} gv){&=9/  
catch(IOException e){e.printStackTrace ();} _'l"Dk  
catch(Exception e){e.printStackTrace ();} O l;DJV  
} (4|R}jv  
5\}E4y  
qRHT~ta-?  
private void processErrorCode(int nErrorCode) 2I283%xr  
{ mpQu:i|W  
System.err.println("Error Code : " + nErrorCode); =1y~Qlu  
} dDa&:L  
0U8'dYf  
2"c5<  
//停止文件下载 nl~ Z,Y$  
public void siteStop() R '8S)'l  
{ 7CH.BY  
bStop = true; 3taGb>15  
for(int i=0;i<nStartPos.length;i++) Bru];%Qg%  
fileSplitterFetch.splitterStop(); ^^F 8M0k3  
0rvBjlFT  
Eihy|p  
} \VWgF)_  
} 7A h   
//负责部分文件的抓取 LTB rg[X  
**FileSplitterFetch.java Bg}l$?S  
*/ BkP4.XRI  
package NetFox; ;*0nPhBw0>  
 DTa!vg  
iNc!z A4  
import java.io.*; [SD mdr1T$  
import java.net.*; P@D\5}*6  
w O Ou/Y  
&TL"Hd  
public class FileSplitterFetch extends Thread { u%lUi2P2E  
?#Y:2LqPC  
p{:y?0pGN  
String sURL; //File URL {+GR/l\!#  
long nStartPos; //File Snippet Start Position O<#8R\v  
long nEndPos; //File Snippet End Position [$td:N *  
int nThreadID; //Thread's ID d]:G#<.  
boolean bDownOver = false; //Downing is over sVGQSJJ5  
boolean bStop = false; //Stop identical ={f8s,m)P,  
FileAccessI fileAccessI = null; //File Access interface 78r0K 5=  
bYZU}Kl;(  
><S(n#EB  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException X8ZO } X  
{ h-RhmQA=Iz  
this.sURL = sURL; {> 8?6m-  
this.nStartPos = nStart; O;i0xWUh  
this.nEndPos = nEnd; ,p /{!BX  
nThreadID = id; ,7k-LAA  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 9_?e, Q  
} BoST?"&}'  
bwcr/J( Nb  
8Lgm50bs  
public void run() cD=IFOB*GD  
{ ,I ][  
while(nStartPos < nEndPos && !bStop)  rV4K@)~  
{ 8e^uKYR<  
7!h> < sx  
?L0k|7  
try{ FvYciU!  
URL url = new URL(sURL); (xoYYO  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); uubIL +  
httpConnection.setRequestProperty("User-Agent","NetFox"); 17,mqXX>  
String sProperty = "bytes="+nStartPos+"-"; +GL$[ 5G  
httpConnection.setRequestProperty("RANGE",sProperty); SWY  
Utility.log(sProperty); RgL>0s  
V"'PA-z3  
p Pag@L  
InputStream input = httpConnection.getInputStream(); 1r_V$o$  
//logResponseHead(httpConnection); cIG7 Q"4  
"a}fwg9Y  
z6rT<~xZtu  
byte[] b = new byte[1024]; PHEQG]H S  
int nRead; u"m(a:jQ  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ^Il*`&+?P  
{ `C C=?E  
nStartPos += fileAccessI.write(b,0,nRead); A<"< DDy  
//if(nThreadID == 1) 7S&$M-k  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); EU>`$M&w-  
} "P54|XIJ\  
"tl$JbRTY  
b GI){0A  
Utility.log("Thread " + nThreadID + " is over!"); %+Y wzL{  
bDownOver = true; >C!^%e;m  
//nPos = fileAccessI.write (b,0,nRead); tl\<:8pI"  
} |FM*1Q[1  
catch(Exception e){e.printStackTrace ();} OXbShA&1  
} h.F=Fhx/1  
} 9=3DYCk/  
j7Ts&;`[*  
% @+j@i`&  
//打印回应的头信息 \!BVf@>p%  
public void logResponseHead(HttpURLConnection con) **kix  
{  X(X[v]  
for(int i=1;;i++) H,5]w\R6\  
{ 3Jlap=]68S  
String header=con.getHeaderFieldKey(i); 3X11Gl  
if(header!=null) 7`&ISRU4  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); : ?BK A0E  
Utility.log(header+" : "+con.getHeaderField(header)); z\A ),;  
else QDV+(  
break; 9A} *  
} rzn,N FI  
} FX|&o >S(8  
O>1Cx4s5  
 w:QO@  
public void splitterStop() zU+q03l8Ur  
{ u;-fG9xs  
bStop = true; )Hmf=eoc  
} ?_^{9q%9  
_UP fqC ?  
kDWEgnXK,v  
} cPNc$^Y  
J;8 d-R5  
X_hDU~5{wC  
/* /B~[,ES@1  
**FileAccess.java z<vh8dNl  
*//文件访问(定位,写) h )5S4)  
package NetFox; v /c]=/  
import java.io.*; 9yC22C:  
ZDbe]9#Xh  
{D Q%fneN4  
public class FileAccessI implements Serializable{ %}VH5s9\  
UWvVYdy7  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 +|,4g_(j  
RandomAccessFile oSavedFile; XgHJ Oqt  
long nPos; -"dt3$ju  
e@ZM&iR  
rFQWgWD  
public FileAccessI() throws IOException n@p@ @  
{ ={zTQ+7S`  
this("",0); 3EICdC  
} ^.!jD+=I  
hyf ;f7`o  
71{jedT  
public FileAccessI(String sName,long nPos) throws IOException A+0-pF2D  
{ r.\L@Y<  
oSavedFile = new RandomAccessFile(sName,"rw"); nwUz}em?O  
this.nPos = nPos; q_h (D/g  
oSavedFile.seek(nPos); V&s|IoTR  
} za@/4z  
uwSSrT  
0>N6.itOz  
public synchronized int write(byte[] b,int nStart,int nLen) J4"Fj, FS  
{ fyb;*hgu  
int n = -1; Pp tuXq%U  
try{ Jq'8"  
oSavedFile.write(b,nStart,nLen); "U-jZ5o"  
n = nLen; 5z!$=SFz  
} XH$r(@Z\7  
catch(IOException e) YiDOV)  
{ '6 F-%  
e.printStackTrace (); =x\`yxsG  
} 7*{f*({  
|2u=3#Jp  
?!U[~Gq  
return n; @I`^\oJ  
} hDW!pnj1  
|j`73@6   
c Rq2 re  
} VIP7j(#t_g  
T+F]hv'  
+ '_t)k^  
/* LnI  
**SiteInfoBean.java rQVX^  
*/ {}$7Bp  
package NetFox; EyE#x_A  
w31Ox1>s  
akzGJ3g  
public class SiteInfoBean { F+V!p4G  
L>h8>JvQ  
nTEN&8Y>R  
private String sSiteURL; //Site's URL Gs,:$Im  
private String sFilePath; //Saved File's Path -V|"T+U  
private String sFileName; //Saved File's Name %'=*utOxy  
private int nSplitter; //Count of Splited Downloading File zXn-E  
67II9\/  
+ O.-o/  
public SiteInfoBean() 2M-[x"\1/  
{//nSplitter的缺省值为5 P9 <U+\z  
//default value of nSplitter is 5 &3[oM)-V  
this("","","",5); I4X9RYB6c  
} "%gsGtS  
eyCZ[SC  
h^yqrDyJ  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) `GCoi ?n7  
{ "tzu.V-  
sSiteURL= sURL; 9Rnypzds  
sFilePath = sPath; }aVZ\PDg  
sFileName = sName; E+]9!fDy<  
this.nSplitter = nSpiltter; N>!:bF  
H4w\e#|  
k2U*dn"9U  
} ?BnU0R_r]  
(j&:  
\!-BR0+y;  
public String getSSiteURL() "+F'WCJ-(*  
{   EO&Q  
return sSiteURL; "]+g5G  
} JL1ajlm~  
WEimJrAn  
^Co$X+  
public void setSSiteURL(String value) vwU1}H  
{ >.iF,[.[F<  
sSiteURL = value; a[-!X7,IU  
} 69g{oo  
`t~jHe4!Y  
2s\ClT  
public String getSFilePath() f2i:I1 p("  
{ 08`|C)Z!  
return sFilePath; #Vq9 =Q2  
} :aesG7=O  
E#B-JLMGl  
?l0eU@rwQ  
public void setSFilePath(String value) E7:xPNU  
{ =:- fK-d  
sFilePath = value;  )(G9[DG  
} HC%Hbc~S_Q  
.A2$C|a*  
=&WIa#!=  
public String getSFileName() 'a ['lF  
{ 5?kfE  
return sFileName; ?h= n5}Y  
} v`HE R6  
nI\6a G?`  
Y}:~6`-jj  
public void setSFileName(String value) k{}> *pCU  
{ 8h=t%zMSb  
sFileName = value; f!9i6  
} b2m={q(s  
8QrpNSj4  
j[G`p^ul  
public int getNSplitter() }aZuCe_  
{ >HP `B2Q H  
return nSplitter; b(iF0U>&  
} )kpEcMlR  
N~v6K}`}  
wVBK Vb9N  
public void setNSplitter(int nCount) i(}Pr A  
{ pHV^K v#  
nSplitter = nCount; r;#"j%z  
} !6!)H8rX  
} 6Y9N= \`  
Kxr@!m"  
x'GB#svi  
/* !+GYu;_  
**Utility.java T8XrmR&?PX  
*/ C= ~c`V5>r  
package NetFox; =&}@GsXdo  
^4dE8Ve"@  
s^h@b!'7  
public class Utility { xE/?ncTK^  
3gA%Q`"  
2c `m=  
public Utility() wPlM= .Hq?  
{ jm}CrqU  
9`tK 9  
Pe`(9&iT.  
} C8U3+ s  
T+kV~ w{  
//线程睡眠 fkA+:j~z_  
public static void sleep(int nSecond) mq`/nAmt  
{ 6_CP?X+T  
try{ !GcBNQ1p+7  
Thread.sleep(nSecond); _olQ;{ U:  
} 5'AP:3Gf"  
catch(Exception e) nBh+UT}  
{ 4Uy%wB  
e.printStackTrace (); =)a24PDG  
} cS ~OxAS  
} 3:)z+#Uk6  
ARKM[]  
//日志 NXW*{b  
public static void log(String sMsg) u,^CFws_  
{ l2D*b93  
System.err.println(sMsg); F2"fOS  
} DB'v7 Ij0  
st-{xC#N#  
8Q'Emw |  
public static void log(int sMsg) $%bSRvA  
{ l/.{F;3F  
System.err.println(sMsg); 5 \mRH  
} uYh!04u  
} ]G/m,Zv*:  
=RoG?gd{R  
eV9U+]C`  
/* Pvxb6\G&d  
**TestMethod.java 3:J>-MO  
*/ AGlBvRX7e  
package NetFox; G@]3EP  
^HKXm#vAB  
oaIk1U;g  
public class TestMethod { ~k"+5bHa*  
@\K[WqF$$q  
vsY?q8+P  
public TestMethod() WtT;y|W  
{ ///xx/weblogic60b2_win.exe 8=8 hbdy;  
try{ lx)^wAO4  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); @DN/]P  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Fr9/TI  
SiteFileFetch fileFetch = new SiteFileFetch(bean); w,UE0i9I  
fileFetch.start(); JJ: ku&Mb  
} >)>f~>  
catch(Exception e){e.printStackTrace ();} gq=t7b  
*1|7%*!8  
ACszx\[K3  
} ,06Sm]4L,  
'Y 38VOI%  
]C_+u_9  
public static void main(String[] args) 'VDWJTia  
{ E~!$&9\  
new TestMethod(); 7=^{~5#  
} U3(+8}Q  
} =[B\50]  
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
批量上传需要先选择文件,再选择上传
认证码:
验证问题:
10+5=?,请输入中文答案:十五