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
  • 11783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
/* O lIH0  
**SiteFileFetch.java  jmNj#R@t  
*/ HcUz2Rm5XP  
package NetFox; 'a[|}nJ3  
import java.io.*; W5uI(rS<6  
import java.net.*; 2^lT!X@  
}iloX#  
vw6FvE`lC  
public class SiteFileFetch extends Thread { 7C yLSZ  
W"@lFUi  
AWNd(B2o  
SiteInfoBean siteInfoBean = null; //文件信息Bean 1/BMs0 =  
long[] nStartPos; //开始位置 A^pp'{ !.  
long[] nEndPos; //结束位置  e) (|  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 8H b|'Q|^  
long nFileLength; //文件长度 K0@7/*%  
boolean bFirst = true; //是否第一次取文件 j06oAer 9  
boolean bStop = false; //停止标志 z Pc;[uHT  
File tmpFile; //文件下载的临时信息 ?{IvA:   
DataOutputStream output; //输出到文件的输出流 @S92D6  
/Q_\h+ `  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) g3rFJc  
public SiteFileFetch(SiteInfoBean bean) throws IOException 0G 1o3[F  
{ cyE2=  
siteInfoBean = bean; xxn&{\ ?  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); l d9#4D[#  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); dfcG'+RU}  
if(tmpFile.exists ()) mjHY-lK  
{ \ChcJth@o<  
bFirst = false; A 6L}5#7-  
read_nPos(); ".ZiR7Z:$Y  
} t}gqk'  
else LeCU"~  
{ Oc`fQqYy  
nStartPos = new long[bean.getNSplitter()]; VA.1J BQ  
nEndPos = new long[bean.getNSplitter()]; ?Sxnq#r#  
} ]H[\~J  
}VRo:sJb  
B)dynGF8i  
<H/H@xQ8G  
} Hkt'~ L*   
$z]l4Hj  
E>D@#I>  
public void run() vGw}e&YI  
{ 0iHI "9z  
//获得文件长度 s_TM!LRUcw  
//分割文件 ]FBfh.#X@  
//实例FileSplitterFetch 0oMMJ6"i   
//启动FileSplitterFetch线程 <-pbLL9  
//等待子线程返回 f7s.\  
try{ -( G2@NG  
if(bFirst) cD6o8v4] ]  
{ 0a'y\f:6*  
nFileLength = getFileSize(); ='j  
if(nFileLength == -1) ez>@'yhK  
{ 4J1Q])G9  
System.err.println("File Length is not known!"); o_n.,=/cZ  
} `h'^S,'*  
else if(nFileLength == -2) ^l,Jbt  
{ RFdN13sJ v  
System.err.println("File is not access!"); 9[*kpMC  
} b4wJnmC8  
else !l|Qyk[  
{  lzuZv$K  
for(int i=0;i<nStartPos.length;i++) ?*;zS%93U9  
{ 2h!3[{M\  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); +}Pa/8ybJ  
} wkGF&U  
for(int i=0;i<nEndPos.length-1;i++) n_<]9  
{ Fk4 3sqU6~  
nEndPos = nStartPos[i+1]; P,wJ@8lv  
} ?cvv!2B]T  
nEndPos[nEndPos.length-1] = nFileLength; 9maw+c!~  
} `dK\VK^  
} jDoWSYu4tY  
D-.>Dw:  
|]Xw1.S.L  
//启动子线程 N%a[Y  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; %YXC-E3@O  
for(int i=0;i<nStartPos.length;i++) ?r+tU  
{ {e^llfj$#  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ]V_9[=%  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ]~P?  
nStartPos,nEndPos,i); =h)H`  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); s$en5)  
fileSplitterFetch.start(); X%dOkHarB  
} ziOmmL(r  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), yZ{YIy~  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); M3V[p9>  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", F8/@/B  
nEndPos = " + nFileLength); X DX_c@U  
// fileSplitterFetch[nPos.length-1].start(); `uU@(  
(F)zj<{f  
mf3G$=[  
//等待子线程结束 )mEF_ &  
//int count = 0; ubL Lhf  
//是否结束while循环 =mZw71,  
boolean breakWhile = false; >i~c>+R  
h^s}8y  
V= _8G3  
while(!bStop) 2{& " 3dq  
{ Gc'H F"w  
write_nPos(); 7XY C.g  
Utility.sleep(500); FKQnz/  
breakWhile = true; IE6/ E  
6f?DW-)jp/  
8,R]R=  
for(int i=0;i<nStartPos.length;i++) OjCT%6hy;  
{ xv2;h4{<  
if(!fileSplitterFetch.bDownOver) yZ 9 *oDs  
{ J kA~Ol  
breakWhile = false; ]-6 G'i?  
break; gk&?h7P"<  
} V>nY?  
} %:y-"m1\u$  
if(breakWhile) LP\ Qwj{  
break; [bcqaT  
Rl(b tr1w  
LD NpEX~  
//count++; }$o%^ "[  
//if(count>4) M *}$$Fe|  
// siteStop(); r*g _  
} Ne[O9D 7  
giTlXz3D9  
%ry>p(-pC(  
System.err.println("文件下载结束!"); bcZuV5F&  
} Y7p#K<y]9  
catch(Exception e){e.printStackTrace ();} r1\.Jz  
} n`hSn41A  
l9Vim9R5T  
X bg7mj9c  
//获得文件长度 ug{F?LW[  
public long getFileSize() jPd<h{js  
{ MG<~{Y84}  
int nFileLength = -1; *iR`mZb  
try{ L{=z}QO  
URL url = new URL(siteInfoBean.getSSiteURL()); K{iYp4pU  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); .UDZW*  
httpConnection.setRequestProperty("User-Agent","NetFox"); MVCCh+,GI  
vxgm0ZOMN  
2H /a&uo@n  
int responseCode=httpConnection.getResponseCode(); GZ e )QH  
if(responseCode>=400) I@\{6hw  
{ 3o?Lz7L  
processErrorCode(responseCode); $D89|sy  
return -2; //-2 represent access is error LY>JE6zTt  
} p$V+IJtO(  
<Du*Re6g  
#Z.JOwi  
String sHeader; l>]M^=,&7  
-lp_~)j^  
f]lDJ?+ M  
for(int i=1;;i++) zknD(%a  
{ c1/x,1LnMf  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ?( '%QfT  
//Utility.log(in.readLine()); %{{#Q]]&  
sHeader=httpConnection.getHeaderFieldKey(i); UOu&sg*o2B  
if(sHeader!=null) aJF`rLm  
{ `MD/C Fl4  
if(sHeader.equals("Content-Length")) Bb o*  
{ N3?d?+A$  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); . FruI#99  
break; 0jmlsC>  
} IF}r%%'Y$  
} mvw:E_  
else WIghP5%W  
break; 8ah]D  
} pGFocw  
} 3:gk:j#  
catch(IOException e){e.printStackTrace ();} )t4C*+9<U  
catch(Exception e){e.printStackTrace ();} lO *Hv9#  
Yem\`; *  
?,NAihN]  
Utility.log(nFileLength); .DQ]q o]OG  
\ C^D2Z6  
c>g%oE  
return nFileLength; I%Awj(9BS  
} tu'MYY  
F)@<ZE  
e#('`vGB  
//保存下载信息(文件指针位置) ~I<y^]2{  
private void write_nPos() RBXoU'.  
{ 2KEww3.{  
try{ .phQ7":`  
output = new DataOutputStream(new FileOutputStream(tmpFile)); DXt^Ym5Cv  
output.writeInt(nStartPos.length); -}J8|gwwp  
for(int i=0;i<nStartPos.length;i++) Oc.>$  
{ ,b4&$W].  
// output.writeLong(nPos); S&*pR3,u  
output.writeLong(fileSplitterFetch.nStartPos); .tNB07=7  
output.writeLong(fileSplitterFetch.nEndPos); m%&B4E#3T  
} )sHPIxHI  
output.close(); 'UxA8i(  
} 5IK@<#wE  
catch(IOException e){e.printStackTrace ();} 2"O Y]d  
catch(Exception e){e.printStackTrace ();} #"_MY-  
} Ei-OuDM;)  
gISs+g  
i'<1xd(`  
//读取保存的下载信息(文件指针位置) B pT&vbY  
private void read_nPos() W=?87PkJu  
{ F!{SeH:  
try{ UZra'+Wb  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); &UR/Txnu  
int nCount = input.readInt(); fsd>4t:" \  
nStartPos = new long[nCount]; }b`*%141  
nEndPos = new long[nCount]; gwJu&HA/  
for(int i=0;i<nStartPos.length;i++) #4M0%rN  
{ Q_.Fw\l$`  
nStartPos = input.readLong(); SfUUo9R(sm  
nEndPos = input.readLong(); "=.|QKC1`  
} {9 O`/|  
input.close(); qgNK!(kWpr  
} x(=x;X$[^  
catch(IOException e){e.printStackTrace ();} v=VmiBq[  
catch(Exception e){e.printStackTrace ();} U@nwSfp:G  
} :8rCCop Uv  
*\",  qMp  
5eA]7$ic  
private void processErrorCode(int nErrorCode) dL(|Y{4  
{ S!_?# ^t  
System.err.println("Error Code : " + nErrorCode); CN(4;-so)  
} sdQv:nd'R  
Oy$BR <\  
Z"X*FzFo  
//停止文件下载 J-F_XKqH  
public void siteStop() 0h4}RmS  
{ ^ {f ^WL=  
bStop = true; NCt sx /C  
for(int i=0;i<nStartPos.length;i++) 2]=I'U<E!  
fileSplitterFetch.splitterStop(); 79H+~1Az  
(}1f]$V  
{LHe 6#  
} EG4bFmcs  
} /}_c7+//  
//负责部分文件的抓取 3ohcHQ/a  
**FileSplitterFetch.java F*VMS  
*/ shIi,!bZ  
package NetFox; N'P,QiR,z<  
- oBas4J  
9X9zIh]JV  
import java.io.*; u 7Y< ~  
import java.net.*; 4!vUksM  
@;D}=$x  
NqE7[wH  
public class FileSplitterFetch extends Thread { A5<Z&Y[  
%C0O?q  
w*%$ lhp!  
String sURL; //File URL O)%kl  
long nStartPos; //File Snippet Start Position (!5}" fj  
long nEndPos; //File Snippet End Position oV>AFs6  
int nThreadID; //Thread's ID %yM' Z[-  
boolean bDownOver = false; //Downing is over #aY<J:Nx  
boolean bStop = false; //Stop identical #r)1<}_e#  
FileAccessI fileAccessI = null; //File Access interface _ZM9 "<M-X  
Kx 185Q'W  
m_02"'  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException [2 w <F[  
{ ;AGs1j  
this.sURL = sURL; *R\/#Y|  
this.nStartPos = nStart; roj04|  
this.nEndPos = nEnd; 6(^Upk=59  
nThreadID = id; p$1Rgm\  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 +<WRB\W  
} :Mu8W_  
NQiecxvt=  
]VG84bFm  
public void run() 3^R][;  
{ '=,rb  
while(nStartPos < nEndPos && !bStop) /z)3gsF  
{ ?WQd  
7|M$W(P  
~? FrI  
try{ g[wP!y%V  
URL url = new URL(sURL); {I9 N6BQ&  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); :O'C:n<g  
httpConnection.setRequestProperty("User-Agent","NetFox"); SeNF!k% Y  
String sProperty = "bytes="+nStartPos+"-";  @6YBK+"  
httpConnection.setRequestProperty("RANGE",sProperty); ?F87C[o  
Utility.log(sProperty); #S53u?JV8  
/x:(SR2,  
]Z$TzT&@%  
InputStream input = httpConnection.getInputStream(); MX`Wg  
//logResponseHead(httpConnection); C*EhexK,}  
'/u:,ar  
k99gjL`  
byte[] b = new byte[1024]; IglJEH[+  
int nRead; tFvgvx\:  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) !M]%8NTt2  
{ Ku0H?qft(  
nStartPos += fileAccessI.write(b,0,nRead); Q@e*$<3  
//if(nThreadID == 1) E)80S.V  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); B3cf] S%  
} }c35FM,  
Sqdc1zC  
YHO;IQ5  
Utility.log("Thread " + nThreadID + " is over!"); S_|9j{w)  
bDownOver = true; (zS2Ndp  
//nPos = fileAccessI.write (b,0,nRead); Y/^[qD  
} % UW=:  
catch(Exception e){e.printStackTrace ();} oN[Fza>  
} -}_cO|kk  
} qab) 1ft  
Q\o$**+{  
JNxW6 cK  
//打印回应的头信息 g{A3W) [ b  
public void logResponseHead(HttpURLConnection con) ` $.X[\*U  
{ Avs7(-L+s  
for(int i=1;;i++) d s|8lz,  
{ d7W%zg\T  
String header=con.getHeaderFieldKey(i); 9Qt)m fqM  
if(header!=null) -GDV[Bg  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); /'&.aGW4%  
Utility.log(header+" : "+con.getHeaderField(header)); `d}W;&c  
else I%;Rn:zl  
break; 2!{_/@I\Y  
} 69[V <1  
} Exep+x-  
TnN^2:cU  
wUru1_zjO  
public void splitterStop() pG,<_N@P  
{ ~a'nHy1  
bStop = true; `"xk,fVYd  
} dr| | !{\  
vQ:x% =]  
4r_!>['`"  
} y!7B,  
Hi]vHG(  
y0scL7/  
/* :0M' =~[  
**FileAccess.java _, \y2&KT  
*//文件访问(定位,写) -]Q3/"Q  
package NetFox; **T:eI+  
import java.io.*; Jq# [uX  
dzgs%qtK  
R&NpdW N  
public class FileAccessI implements Serializable{ t *o7,  
^D9 /  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 l*QIoRYFW  
RandomAccessFile oSavedFile; pZu?V"R  
long nPos; d>^~9X  
$|Q".dD  
qzz[y#q(  
public FileAccessI() throws IOException |2qR^Hd&5  
{ w>v5oy8s-  
this("",0); !IO&&\5  
} $TR=3[j  
M_tj7Q3 W  
53bM+  
public FileAccessI(String sName,long nPos) throws IOException {VBR/M(q  
{ lxm*;?j`W  
oSavedFile = new RandomAccessFile(sName,"rw"); gB>(xY>LrA  
this.nPos = nPos; .H Fc9^.*  
oSavedFile.seek(nPos); F\;2 i:(  
} k& OC&  
0xN!DvCg>.  
IS-}:~Pi  
public synchronized int write(byte[] b,int nStart,int nLen) \.5F](:  
{ *:?QB8YJ  
int n = -1; :b"= KQ  
try{ +IvNyj|  
oSavedFile.write(b,nStart,nLen); <BZ_ (H  
n = nLen; =ntft SH  
} ,cLH*@  
catch(IOException e) Og +)J9#  
{ B i'd5B5  
e.printStackTrace (); %z30=?VL  
} `q^(SM  
WmNA5;<Q  
{JXf*IJ  
return n; B<Ol+)@,}  
} 3]N q@t  
)W#T2Z>N1  
L,#^&9bHa#  
} (/-lV&eR  
l/[pEUYU  
)Q~C4C-j  
/* KVg[#~3  
**SiteInfoBean.java Cb4_ ?OR0  
*/ {y1q7Z.M  
package NetFox; V- /YNRV  
aFyh,  
04~}IbeJ  
public class SiteInfoBean { eap8*ONl  
Cpe#[mE  
Zd$JW=KR]l  
private String sSiteURL; //Site's URL t-x[:i  
private String sFilePath; //Saved File's Path dIvy!d2l  
private String sFileName; //Saved File's Name c+~Lp SQ  
private int nSplitter; //Count of Splited Downloading File &Bm&i.r  
"w9`cz9a~J  
x7H A722w  
public SiteInfoBean() 9j0o&Xn  
{//nSplitter的缺省值为5 se#@)LtZ  
//default value of nSplitter is 5 {tc57jsr  
this("","","",5); ?.Q3 pUT  
} drI\iae{^  
g>yry}>04%  
zSKKr?{  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) 6Kp}_^|z  
{ yyjw?#\8  
sSiteURL= sURL; $~G@   
sFilePath = sPath; O5M2`6|As  
sFileName = sName; x}|+sS,g  
this.nSplitter = nSpiltter; Wxn#Rk#>  
"W5rx8a  
rI>LjHP  
} >azEed<B  
gHZqA_*T8U  
<aXoB*Y  
public String getSSiteURL() 2T?TM! \Q  
{ `BjR.xMv  
return sSiteURL; WL1\y|  
} 8SZK:VE@  
m]P/if7  
<h@]Ri  
public void setSSiteURL(String value) n]iyFZ`9  
{ uXpv*i {R  
sSiteURL = value; #1gO?N(<=  
} #)]E8=}  
WqQU@sA  
E30Z`$cz:  
public String getSFilePath() +>}o;`hPe  
{ {m[Wyb(  
return sFilePath; j^nu|  
} =) }nLS3t  
TF2KZL#A|  
F&az":  
public void setSFilePath(String value) 'Wp @b678  
{ ?Oc -aa  
sFilePath = value; T?rH ,$:  
} q:]Q% IC^  
``4?a7!!  
b 4OnZ;FI  
public String getSFileName() d.AC%&W  
{ Z0\Iyc G  
return sFileName; hZU 1O  
} M*`hDdS  
x.UaQ |F  
ShGp^xVj  
public void setSFileName(String value) H+x#gK2l  
{ F#|Z# Mu  
sFileName = value; b#='^W3  
} !8/gL  
MGaiTN^_<  
gDC2 >nV  
public int getNSplitter() Hi8Y6|y$D  
{ g~)3WfC$[  
return nSplitter; B}\BeFt'  
} m\-PU z&C  
FYl3c   
x{hn2]6+eB  
public void setNSplitter(int nCount) wOg,SMiq  
{ JA6";fl;  
nSplitter = nCount; S>t>6&A  
} #jP/k.  
} <\aU"_D   
A3q*$.[  
l$M +.GB<  
/* 1<,/ -H  
**Utility.java A*i_|]Q  
*/ jQ$BPEG&X  
package NetFox; -J?~U2  
vgThK9{m;  
:Q- F9o J  
public class Utility { ri+U0[e3  
sfI N)jh  
%?=)!;[  
public Utility() m UgRm]  
{ ~gddcTp  
KlO(o#&N  
( 3;`bvYH"  
} I%xn,u  
KyLp?!|>  
//线程睡眠 \ja `c)x  
public static void sleep(int nSecond) t)r1"oA  
{ #{,h@g}W  
try{ jdlG#j-\  
Thread.sleep(nSecond); jVYH;B%%z  
} Kv?;cu!  
catch(Exception e) H.~bD[gA  
{ HcO5?{2  
e.printStackTrace (); n(R_#,Hs  
} 8*Zvr&B,G  
} [`nY2[A$  
XKSX#cia  
//日志 Le&;g4%  
public static void log(String sMsg) ^'W%X  
{ d?7BxYaa  
System.err.println(sMsg); ) b:4uK A  
} 5~l2!PY  
7\%$>< K  
CQ>]jQ,2  
public static void log(int sMsg) 7I3:u+  
{ 5i9Ub |!P  
System.err.println(sMsg); 2AK}D%jfc  
} 0N5bPb  
} SRWg[H  
usH%dzKK  
^Y 7U1I  
/* bQ.nFa']  
**TestMethod.java V6*?$o  
*/ FL&dv  
package NetFox; !*bdG(pK  
3EOyq^I%  
@C_ =*  
public class TestMethod { !. eAOuq  
$W,zO|-  
3:AU:  
public TestMethod() ,`)OEI|1d  
{ ///xx/weblogic60b2_win.exe PbN3;c3  
try{ hS_.l}0yf  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 8A4TAT4,  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); {(0Id!  
SiteFileFetch fileFetch = new SiteFileFetch(bean); G?ZC 9w]rA  
fileFetch.start(); !Bj^i cR  
} t= *Jg/$  
catch(Exception e){e.printStackTrace ();} A^L?_\e6  
Tzf$*Uje3  
yxY h?ka  
} KBj@V6Q  
r0uJ$/!  
8<c' x]~  
public static void main(String[] args) kQ[Jo%YT?E  
{ 5p{25N_t  
new TestMethod(); WG\Q5k4Ba  
} -R8/`M8GbD  
} t%HI1eO7h  
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:
3+5=?,请输入中文答案:八 正确答案:八