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
  • 10689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
/* %97IXrE  
**SiteFileFetch.java @qH<4`y.^  
*/ c)M_&?J!5  
package NetFox; -~ `5kO~  
import java.io.*; 2Fce| Tn  
import java.net.*; It4J \S  
@M"h_Z1#  
pVw)"\S%  
public class SiteFileFetch extends Thread { c|Nv^V*2  
d3(T=9;f2  
- iS\3P.  
SiteInfoBean siteInfoBean = null; //文件信息Bean mD)_quz.sk  
long[] nStartPos; //开始位置 oZ@_o3VG  
long[] nEndPos; //结束位置 "@E1^  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 W]n%$a  
long nFileLength; //文件长度 k"V3FXC)  
boolean bFirst = true; //是否第一次取文件 3 $Uv  
boolean bStop = false; //停止标志 c`y[V6q9  
File tmpFile; //文件下载的临时信息 Vcl"qz@Fj  
DataOutputStream output; //输出到文件的输出流 <vA^%D<\~  
}$;T.[ ~  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) fdzD6K ZI  
public SiteFileFetch(SiteInfoBean bean) throws IOException >=i47-H  
{ v. ,C"^W  
siteInfoBean = bean; Srz.-,2PF  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); .)B_~tct  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); yU*j{>%RsK  
if(tmpFile.exists ()) 'j!7 O+7y  
{ 6pQ#Zg()vp  
bFirst = false; ^[8e|,U  
read_nPos(); (9$/r/-a  
} 8sg8gBt  
else >\$qF  
{ JB'q_dS}  
nStartPos = new long[bean.getNSplitter()]; r%$-F2.p  
nEndPos = new long[bean.getNSplitter()]; kkFE9:[-c&  
} M>0=A  
][6$$ Lz  
g{f1JTJ7  
\A5cM\-  
} U^~K-!0  
H4 & d,8:m  
>u~ [{(d ,  
public void run() >&aFSL,f  
{ ^`\c;!)F<  
//获得文件长度 IX^k<Jqr  
//分割文件 Jnm{i|6N  
//实例FileSplitterFetch f 7et  
//启动FileSplitterFetch线程 ?U2ed)zzw  
//等待子线程返回 }jfU qqFd  
try{ +vLuzM-  
if(bFirst) 'sY>(D*CQ  
{ co<){5zOT  
nFileLength = getFileSize(); 7vcYI#(2 Y  
if(nFileLength == -1) klKAwCQ,  
{ @ MNL  
System.err.println("File Length is not known!"); < 7zyRm@S  
} g^ ^%4Y  
else if(nFileLength == -2) fh )QX  
{ @iy ^a  
System.err.println("File is not access!"); )"jG)c^1*  
} i,FG?\x@  
else _ts0@Z_:  
{ netKt_  
for(int i=0;i<nStartPos.length;i++) _$wWKJy9  
{ i?'HVx  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); &m4 \"X@  
} M,t8<y4 W/  
for(int i=0;i<nEndPos.length-1;i++) @"kA&=0;|J  
{ djPr 4Nog  
nEndPos = nStartPos[i+1]; v (=fV/  
} rc*&K#? B  
nEndPos[nEndPos.length-1] = nFileLength; nV McHN   
} HQaKG4Z  
} =5%jKHo+9z  
~5`rv1$  
"(/|[7D)  
//启动子线程 l?a(=  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ?qw&H /R  
for(int i=0;i<nStartPos.length;i++) u|WX?@\  
{ 2ADUJ  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), %zd1\We  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 7l7eUy/z  
nStartPos,nEndPos,i); vf~q%+UqK  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); .ymR%X_k  
fileSplitterFetch.start(); *2 4P T7  
} ZHICpL  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), +sE81B  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); Vs8os+  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", y*\ M7}](  
nEndPos = " + nFileLength); X&^t 8  
// fileSplitterFetch[nPos.length-1].start(); \H<'W"  
L`x:Y>C(  
_"a(vfl#  
//等待子线程结束 \@['V   
//int count = 0; rd0BvQ9TK  
//是否结束while循环 l8GziM{lp  
boolean breakWhile = false; \?GUGs  
`\q4z-<-  
j"_V+)SD  
while(!bStop) p."pI Bd  
{ vV#Jl) A  
write_nPos(); +tdt>)a  
Utility.sleep(500); (~}yt.7K  
breakWhile = true; 20 zIO.&o  
zBB4lC{q  
"KW\:uc /  
for(int i=0;i<nStartPos.length;i++) &>@nW!n u  
{ @6 gA4h  
if(!fileSplitterFetch.bDownOver) 0$}+tq+  
{ uc=-+*D'I  
breakWhile = false; @XDU !<N  
break; ;TMH.E,h:  
} z6|P]u  
} E} Uy-  
if(breakWhile) 6rt.ec(  
break; .4_EaQ;jX  
rNfua   
0}PW?t76  
//count++; =o{zw+|% %  
//if(count>4) ',kYZay  
// siteStop(); Xn$]DE/r}N  
} $62ospR^Y  
V`S6cmwdc\  
GZXUB0W\@)  
System.err.println("文件下载结束!"); uzho>p[ae  
} H`),PY2  
catch(Exception e){e.printStackTrace ();} WSi Utf|g  
} _ 97F  
l]T|QhiVd  
sA3 4`ZAa  
//获得文件长度 '"~|L>F%G  
public long getFileSize() lb{*,S  
{ N: d`L+tcc  
int nFileLength = -1; !(uyqplTk  
try{ )3'/g`c  
URL url = new URL(siteInfoBean.getSSiteURL()); ["MF-tQ5  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 22}J.'Zb  
httpConnection.setRequestProperty("User-Agent","NetFox"); .9lx@6]+  
_s|C0Pt  
HR\yJt  
int responseCode=httpConnection.getResponseCode(); < I8hy$+6  
if(responseCode>=400) {/XzIOO;b  
{ p!|Wp  
processErrorCode(responseCode); 2[r#y1ro  
return -2; //-2 represent access is error k U*\Fa*E  
} d=xU f`^  
8!b#ez   
8g(%6 ET  
String sHeader; ~BrERUk  
c/x ^I{b*  
t$]lK6  
for(int i=1;;i++) iKLN !QR  
{ Wl;F]_|*(  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); (t>BO`,  
//Utility.log(in.readLine()); jNaK]  
sHeader=httpConnection.getHeaderFieldKey(i); $MfHA~^  
if(sHeader!=null) S,n*1&ogj  
{ ~U~KUL|  
if(sHeader.equals("Content-Length")) _?Rprmjx}  
{ Y71io^td~j  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); *]W{83rXQ  
break; ;pBSGr 9  
} ,kpk XK  
} Zh{Pzyp  
else yJppPIW^  
break; -% 5*c61  
} (pREo/T  
} &h`s:Y  
catch(IOException e){e.printStackTrace ();} [Sg1\UTl  
catch(Exception e){e.printStackTrace ();} &Jk0SUk MP  
8JJqEkQ  
Fv.}w_  
Utility.log(nFileLength); Gi6sl_"q  
h-<('w:A  
S'9T>&<Kn  
return nFileLength; //3iai  
} U;`N:~|p#  
r_@;eh  
Eu l,1yR  
//保存下载信息(文件指针位置) (6^v`SZ  
private void write_nPos() ,=Xr'7w,  
{ *6df|q  
try{ O:{I9V-=>s  
output = new DataOutputStream(new FileOutputStream(tmpFile)); k_ UY^vz.  
output.writeInt(nStartPos.length); Ra%RcUf~sh  
for(int i=0;i<nStartPos.length;i++) SBzJQt@Hs  
{ #i%it  
// output.writeLong(nPos); Kxn/@@z>u  
output.writeLong(fileSplitterFetch.nStartPos); |b QKymS  
output.writeLong(fileSplitterFetch.nEndPos); i!*w'[G->Y  
} q}*(rR9/Br  
output.close(); [v^T]L  
} CJz2.yd  
catch(IOException e){e.printStackTrace ();} 5qt]~v%y  
catch(Exception e){e.printStackTrace ();} zFN:C()ig  
} Cf91#% :cN  
b" 1a7   
FF0N{bY  
//读取保存的下载信息(文件指针位置) p3&/F=T;)  
private void read_nPos() x{*g^f  
{ WUvrC  
try{ f<=<:+  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); S*Qip,u  
int nCount = input.readInt(); A0m  
nStartPos = new long[nCount]; :"5i/Cx  
nEndPos = new long[nCount]; n!2"pRIi  
for(int i=0;i<nStartPos.length;i++) AME3hA  
{ )^qM%k8  
nStartPos = input.readLong(); cV\(Z6u  
nEndPos = input.readLong(); xdFm-_\-  
} -y5^xR  
input.close(); YiJnh47  
} }%c2u/PQ  
catch(IOException e){e.printStackTrace ();} ^ |z|kc  
catch(Exception e){e.printStackTrace ();} O:IU|INq8  
} JF!JY( U,  
yS^";$2Tc  
mKugb_d?  
private void processErrorCode(int nErrorCode) b|^g51v  
{ R9A8)dDz  
System.err.println("Error Code : " + nErrorCode); ]i(tou-[i  
} (dd+wx't  
v8Vw.Ce`f  
;PCnEs  
//停止文件下载 NoTEbFrV  
public void siteStop() Se.\wkl#Y  
{ _PLY<i2vr  
bStop = true; VCSHq&p8  
for(int i=0;i<nStartPos.length;i++) i ?&t@"'  
fileSplitterFetch.splitterStop(); twv|,kM  
:hJHjh  
n+QUT   
} Ebw1 %W KC  
} cKJf0S:cx-  
//负责部分文件的抓取 cXU8}>qY7  
**FileSplitterFetch.java @<=xfs  
*/ Uy2NZ%rnt  
package NetFox; "(zvI>A  
)h6hN"#V5  
gHdNqOy c  
import java.io.*; Px{Cvc  
import java.net.*; e/Wrm^]y  
V T8PV5z  
jd8`D6|Z  
public class FileSplitterFetch extends Thread { f4UnLig  
*oopdGue  
ZUePHI-dP  
String sURL; //File URL UF0W%Z  
long nStartPos; //File Snippet Start Position ,n<t':-  
long nEndPos; //File Snippet End Position 'n4Ro|kA  
int nThreadID; //Thread's ID s~ ||Vv!  
boolean bDownOver = false; //Downing is over nr7#}pzo  
boolean bStop = false; //Stop identical me:~q#k  
FileAccessI fileAccessI = null; //File Access interface Q&+Jeji  
F*m^AFjs  
a~ q_2S]h  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException nGQc;p5;  
{ O'm><a>8  
this.sURL = sURL; O<7Q>m  
this.nStartPos = nStart; t"x 8]Gy  
this.nEndPos = nEnd; ,I6jfXI4  
nThreadID = id; M8dv y!D  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 uu ahR  
} jr[(g:L   
)[fjZG[  
[Jv0^"]  
public void run() "yaz!?O>  
{ O AJGwm  
while(nStartPos < nEndPos && !bStop) rQmDpoy=  
{ Y-!~x0-H  
|osu4=s|  
XJg8-)T#  
try{ j/.$ (E   
URL url = new URL(sURL); \ #<.&`8B  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); G>Fk )  
httpConnection.setRequestProperty("User-Agent","NetFox"); \WS2g"(  
String sProperty = "bytes="+nStartPos+"-"; }L mhM  
httpConnection.setRequestProperty("RANGE",sProperty); ffoL]u\  
Utility.log(sProperty); <A|X4;  
3y^PKIIrt  
%Ms"LoK  
InputStream input = httpConnection.getInputStream(); H<_BnT #  
//logResponseHead(httpConnection); dbn9t7'{  
L\0;)eJ#M  
LLyw9y1  
byte[] b = new byte[1024]; %+ln_lgD:  
int nRead; aa|u *afWQ  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) UWU(6J|Fk  
{ ] V|hDU=t  
nStartPos += fileAccessI.write(b,0,nRead); xgDd5`W  
//if(nThreadID == 1) 5OEo(&  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); g)?Ol  
} CD^C}MB  
I0iTa99K  
k=]#)A(#C  
Utility.log("Thread " + nThreadID + " is over!"); -M]B;[^  
bDownOver = true; $Lj~ge3#  
//nPos = fileAccessI.write (b,0,nRead); >+ ,w2m@0  
} uqz HS>GM  
catch(Exception e){e.printStackTrace ();} ?'_Ty`vT  
} Cws;6i*=@  
} s!k7Wwj  
G5WQTMzf&  
d]A.=NAc  
//打印回应的头信息 PP*6nW8  
public void logResponseHead(HttpURLConnection con) u<L<o 2  
{ Sg%h}]~   
for(int i=1;;i++) wnioIpRkh  
{ KA $jG{ yq  
String header=con.getHeaderFieldKey(i); -VZn`6%s  
if(header!=null) DWv(|gO  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); Lql2ry$Wa  
Utility.log(header+" : "+con.getHeaderField(header)); cNbH:r"Ay  
else oW}nr<G{<  
break; } 6 ,m2u  
} n[S-bzU^t  
} LNz  
./ ]xn  
Q};n%&n&  
public void splitterStop() fe!eZiE  
{ < `$svM  
bStop = true; mpr_AL!ZO~  
} epicY  
}b5omHUE%  
G2$<Q+UYs?  
} jz,K>   
QhhL_vP  
GB%kxtGD;\  
/* O2pntKI  
**FileAccess.java q t(+X  
*//文件访问(定位,写) Hs:0j$  
package NetFox; 1d$qr`  
import java.io.*; t1JU_P  
sX@}4[)<&  
e{EC# %x_  
public class FileAccessI implements Serializable{ kzE<Y  
,? >{M  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 NX[-Y]t  
RandomAccessFile oSavedFile; ]OSq}ul  
long nPos; >jU25"XI[  
0g 2?  
a8WWFAC[  
public FileAccessI() throws IOException }/w]+f*  
{ m?< ^b_a}  
this("",0); ~8 B]  
} {+~ JTrp  
 -uKTEG[  
Ypx5:gm|J  
public FileAccessI(String sName,long nPos) throws IOException 0OXl`V`w  
{ A"e4w?  
oSavedFile = new RandomAccessFile(sName,"rw"); 1[yy/v'q  
this.nPos = nPos; YdZ9##IU3  
oSavedFile.seek(nPos); #<LJns\t   
} ?gsPHPUS  
j.&Y'C7GOC  
o%b6"_~%3  
public synchronized int write(byte[] b,int nStart,int nLen) /78zs-  
{ ;J@U){R  
int n = -1; XS}-@5TI  
try{ 216`rQ}z  
oSavedFile.write(b,nStart,nLen); )x,/+R]{8l  
n = nLen; 2tb+3K1  
} {RGQX"k  
catch(IOException e) 7lx" X0w*m  
{ {Gr"lOi*@  
e.printStackTrace (); r6eZ-V`4  
} _1?nLx7n  
XDYQV.Bv  
5tI#UBha  
return n; zv7)JH7EV&  
} \0W0o5c$  
v <Ywfb  
mm9uhlV8  
} =F2`X#x_j  
{ 2%'=v  
`;=-71Gn~  
/* p[O\}MAd#  
**SiteInfoBean.java 86pA+c+U  
*/ g~ii^[W  
package NetFox; %aI,K0\  
i zYC0T9  
ken.#>w  
public class SiteInfoBean { =H`yzGt  
X }`o9]y  
xnC:?d  
private String sSiteURL; //Site's URL @Di!~e6  
private String sFilePath; //Saved File's Path VKtlAfXy~  
private String sFileName; //Saved File's Name b^STegz  
private int nSplitter; //Count of Splited Downloading File YQ@2p?4m  
p"FWAC!  
? 'qyI^m@  
public SiteInfoBean() v, CWE  
{//nSplitter的缺省值为5 xk  
//default value of nSplitter is 5 3RX9LJGX  
this("","","",5); TCFr-*x  
} (q0vql  
\11+~  
M&jlUr&l  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) {!j)j6(NY  
{ L PS,\+  
sSiteURL= sURL; S&'?L0  
sFilePath = sPath; v}J0j  
sFileName = sName; fP[S.7F+No  
this.nSplitter = nSpiltter; 2FW"uYA;6  
1 0zw}1x  
K^6d_b&  
} (Hmm^MV)  
gAh#H ?MM  
{{Qbu }/@  
public String getSSiteURL() `T+w5ONn  
{ qw*) R#=  
return sSiteURL; P:_bF>r ?  
} 0K6My4d{  
r7sA;Y\  
SA#01}&p  
public void setSSiteURL(String value) obGhO  
{ k dWUz(  
sSiteURL = value; k+%&dEE|vH  
} ?(U a+*b  
73 4t  
RH:vd|q+  
public String getSFilePath() <@# g2b  
{ Y]=k"]:%  
return sFilePath; "hQGk  
} cRMyYdJ o  
: h(Z\D_  
gkX7,J-0  
public void setSFilePath(String value) 0VrsbkS  
{ Z ^}[CQ&Am  
sFilePath = value; {/(.Bpld  
} (t\U5-w  
'Hzc"<2Y\  
$hHV Ie]+  
public String getSFileName() *Ojl@N  
{ L+VQtp &"  
return sFileName; Q)y5'u qZ  
} mo3A*|U  
"G-h8IN^O  
kxN O9w  
public void setSFileName(String value) 7AS_Aw1L  
{ 98)C 7N'  
sFileName = value; xmEom  
} Y+o\?|q-E  
[KFCc_:  
q2r$j\L%  
public int getNSplitter() o ^ \+Ua  
{ mBJr*_p  
return nSplitter; R8:5N3Fx  
} jV9oTH-  
qp)Wt6 k?  
TpwN2 =  
public void setNSplitter(int nCount) 7R7+jL,  
{ Be6+YM5Cl  
nSplitter = nCount; xkw=os  
} dA (n,@{  
} z;dRzwL  
-%]1q#C>@  
rQ_]%ies8  
/* t,dm3+R  
**Utility.java Ssuz%*  
*/ Xz)qtDN|(  
package NetFox; <5mv8'{L  
w3"L5;oH  
`Oi#`lC\  
public class Utility { A)4XQF  
^a`3)WBv8  
dHTx^1  
public Utility() -Ci&h  
{ 5 2 Qr  
)`(]jx!  
SASLeGaV  
} jI0gf&v8  
c|`$ h  
//线程睡眠 Zhv%mUj~  
public static void sleep(int nSecond) Ef?hkq7X<  
{ 7)Vbp--b#  
try{ iF MfBg  
Thread.sleep(nSecond); i\l}M]Z#  
} <G|i5/|7  
catch(Exception e) i9De+3VqKK  
{ :fwtPvLo  
e.printStackTrace (); zeuj  
} K6 >\4'q  
} 8PH4v\tJEK  
mNacLkh[  
//日志 0ug&HEl_w  
public static void log(String sMsg) gpf0 -g-X  
{ ;3wO1'=  
System.err.println(sMsg); $H[q5(_~  
} 5O d]rE  
p4MWX12  
'8\9@wzv  
public static void log(int sMsg) b=xn(HE8|  
{ $ ,]U~7S  
System.err.println(sMsg); ~Gz9pBv1  
} e3W~6P  
} &Jb\}c}  
dr}PjwW%  
PZJ9f8 V  
/* f+hHc8g  
**TestMethod.java );VuZsmi  
*/ T]Ai{@i  
package NetFox; ls&H oJ7  
{QylNC9  
mB"I(>q*M  
public class TestMethod { t"YsIOT:O"  
!OY}`a(z  
tE {M  
public TestMethod() e2N K7  
{ ///xx/weblogic60b2_win.exe d6'G 7'9  
try{ pvUV5^B(M  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); jq*`| m;Q  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); #"rK1Z  
SiteFileFetch fileFetch = new SiteFileFetch(bean); `R: W5_n  
fileFetch.start(); zD<W`_z  
} <{bxOr+  
catch(Exception e){e.printStackTrace ();} Q2- lHn^L:  
sH;_U)ssH  
7+hF1eoI  
} isd-b]@:Lc  
TUC)S&bC  
YfB)TK\W9/  
public static void main(String[] args) 85H \v_[  
{ u "jV#,,  
new TestMethod(); RU4X#gP4Vh  
} (@5`beEd  
} (^y"'B  
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