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
  • 11745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
/* dOYmt,  
**SiteFileFetch.java 6{,K7FL  
*/ }G:uzud10  
package NetFox; S<bz7 k9  
import java.io.*; O'yjB$j  
import java.net.*; ")[Q4H;V  
JQVw6*u{  
;JD3tM<  
public class SiteFileFetch extends Thread { Gh>fp  
;Kd{h  
"a%ASy>?g  
SiteInfoBean siteInfoBean = null; //文件信息Bean E?c{02fu  
long[] nStartPos; //开始位置 GF/x;,Ae  
long[] nEndPos; //结束位置 I}]@e ^ ~  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 gP hw.e""  
long nFileLength; //文件长度 +e3WwUx  
boolean bFirst = true; //是否第一次取文件 po](6V  
boolean bStop = false; //停止标志 { ves@p>?  
File tmpFile; //文件下载的临时信息 35]G_\  
DataOutputStream output; //输出到文件的输出流 {dr&46$p  
zL!~,B8C  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) (gJ )]/n  
public SiteFileFetch(SiteInfoBean bean) throws IOException .8uwg@yD  
{ Dy!bj  
siteInfoBean = bean; 5}l#zj  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); 7)6Yfa]I%  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); [E :`jY  
if(tmpFile.exists ()) h9OL%n 7m'  
{ 0)]C&;}_M  
bFirst = false; SYW= L  
read_nPos(); ^*UfCoj9Z  
}  W$VCST  
else GO GXM4I  
{ -L4G WJ~.-  
nStartPos = new long[bean.getNSplitter()]; %F]9^C+  
nEndPos = new long[bean.getNSplitter()]; n4_:#L?  
} 'rq#q)1MT  
{uQ)p=  
"VVR#H}{  
,IZxlf%  
} gBiQIhz  
r(2'0JQ  
: R*^Izs=  
public void run() V1fvQ=9  
{ j'Q-*-3  
//获得文件长度 cZX&itVc:  
//分割文件 -O> mY)  
//实例FileSplitterFetch mP .&fS  
//启动FileSplitterFetch线程 `zOAltfd  
//等待子线程返回 <B{VL8IA>  
try{ Wv*BwiQ  
if(bFirst) $^D(%  
{ (>5VS  
nFileLength = getFileSize(); Jc#)T;# 6  
if(nFileLength == -1) *Wo$ $T  
{ t~W4o8<w  
System.err.println("File Length is not known!"); % oL&~6l$  
} SoGLsO+R  
else if(nFileLength == -2) W;}u 2GH  
{  |ukdn2Q  
System.err.println("File is not access!"); bz@=zLBt  
} 'GdlqbX(%  
else J ]^gF|  
{ A%8`zR  
for(int i=0;i<nStartPos.length;i++) uV$d7(N}"  
{ &*:)5F5  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); 7LZb*+>  
} ].T;x|  
for(int i=0;i<nEndPos.length-1;i++) 5!Mp#lO  
{ C`T5d  
nEndPos = nStartPos[i+1]; Ac(irPrD  
} f<U m2YGW  
nEndPos[nEndPos.length-1] = nFileLength; |iJZC  
} 9n\#s~,  
} -/7=\kao%  
h+u|MdOY\  
=v`&iL~m  
//启动子线程 y^|3]G3  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; j%y+W{Q[  
for(int i=0;i<nStartPos.length;i++) hA1hE?c`  
{ &OR*r7*Z  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), w[vIPlSdS  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), x4A~MuGU  
nStartPos,nEndPos,i); wQS w&G  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); $ 5-2 cL  
fileSplitterFetch.start(); @`*YZq>p  
} L , Fso./y  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M~Dc5\T  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); f#Oz("d  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", %=O!K>^vt<  
nEndPos = " + nFileLength); 4^}PnU7z  
// fileSplitterFetch[nPos.length-1].start(); }`FC__  
{Qmb!`F  
uqeWdj*Y  
//等待子线程结束 N6 (w<b  
//int count = 0; k)' z<EL6c  
//是否结束while循环 CIvT5^}  
boolean breakWhile = false; 7Bd_/A($  
'R5l =Wf  
nln[V$   
while(!bStop) HZ4 ^T7G  
{ I[IQFka}  
write_nPos(); OiEaVPSI;  
Utility.sleep(500); `rJ ~*7-  
breakWhile = true; J` --O(8Ml  
M@[gT?m v1  
]@T `q R  
for(int i=0;i<nStartPos.length;i++) X1qj l_A  
{ Guc^gq}  
if(!fileSplitterFetch.bDownOver) cDyC&}:f  
{ J|8YB3K,  
breakWhile = false; N!&VBx^z  
break; zvC,([  
} "A`'~]/hE  
} `;2`H, G'  
if(breakWhile) Xn'>k[}<k  
break; 19`0)pzZ*P  
JN-8\ L  
U*h)nc  
//count++; \eN/fTPm  
//if(count>4) ew['9  
// siteStop(); 1vudT&  
} <$6E r  
FdHWF|D  
_u5U> w  
System.err.println("文件下载结束!"); +N&(lj  
} w.- i !Ls  
catch(Exception e){e.printStackTrace ();} %4K#<b"W  
} %d\+(:uu/  
iPYlTV  
wf$ JuHPt  
//获得文件长度 (W/UR9x)|d  
public long getFileSize() e2ZUl` {g  
{ L KR,CPz  
int nFileLength = -1; ,R6$SrNcd  
try{ ZWEzL$VWi  
URL url = new URL(siteInfoBean.getSSiteURL()); F4gc_>{|  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !qve1H4d2  
httpConnection.setRequestProperty("User-Agent","NetFox"); t4f\0`jN  
YWF<2l.  
v]S8!wU  
int responseCode=httpConnection.getResponseCode(); bZfJG^3  
if(responseCode>=400) %,RU)}  
{ lB@K;E@r8  
processErrorCode(responseCode); =R`2m  
return -2; //-2 represent access is error !PbFo%)  
} ?V&a |:N9  
nEr, jd~f  
K6hN N$F!  
String sHeader; +q%goG8  
PyE<`E  
dBn.DU*B  
for(int i=1;;i++) `d#_66TLr  
{ +=$G6uR$  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); j'n= Xh  
//Utility.log(in.readLine()); j`l K}  
sHeader=httpConnection.getHeaderFieldKey(i); _zwuK1e  
if(sHeader!=null) M/;g|J jM  
{ ^Tmmx_Xw  
if(sHeader.equals("Content-Length")) 6 nhB1Aei  
{  t/(j8w  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); FM];+d0  
break; b=EZtk6>  
} 9Ua@-  
} /% 1lJD  
else ]h@:Y]  
break; OSU=O  
} Q)&Ztw<  
} mj~CCokF{?  
catch(IOException e){e.printStackTrace ();} Y [S^&pF  
catch(Exception e){e.printStackTrace ();} *%sYajmD  
P*]g*&*Y +  
;oE4,  
Utility.log(nFileLength); Lq^/Z4L  
VTa8.(i6v  
f#mpd]e+6  
return nFileLength; -XB>&dNl)T  
} z ZQoY_UI  
dGjvSK<1@  
K2Zy6lGOZ  
//保存下载信息(文件指针位置) I*"]!z1  
private void write_nPos() ;'}xD5]  
{ _Qas+8NW  
try{ Jsl,r+'H  
output = new DataOutputStream(new FileOutputStream(tmpFile)); R)z|("%ec  
output.writeInt(nStartPos.length); v>R.ou(  
for(int i=0;i<nStartPos.length;i++) =c'LG   
{ A:Z:&(NtE:  
// output.writeLong(nPos); K.~U%v}  
output.writeLong(fileSplitterFetch.nStartPos); #$E vybETx  
output.writeLong(fileSplitterFetch.nEndPos); ,5:86'p  
} +0DIN4Y(4  
output.close(); C54)eT6  
} _u; UU$~  
catch(IOException e){e.printStackTrace ();} HL]?CWtGP  
catch(Exception e){e.printStackTrace ();} xm5D$m3#  
} P2kZi=0  
huIr*)r&p  
lvlH5Fc  
//读取保存的下载信息(文件指针位置) %iv'/B8  
private void read_nPos() wd *Jq  
{ E3qX$|.$/  
try{ $? Rod;  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); q[lqEc  
int nCount = input.readInt(); pV8,b   
nStartPos = new long[nCount]; - _(!  
nEndPos = new long[nCount]; zO,sq%vQn'  
for(int i=0;i<nStartPos.length;i++) /^"TMm   
{ .wywO|  
nStartPos = input.readLong(); >xN^#$ng}  
nEndPos = input.readLong(); gUcE,L  
}  CgWj9 [  
input.close(); Pcc%VQN  
} A 3l1$t#w  
catch(IOException e){e.printStackTrace ();} )NK2uD  
catch(Exception e){e.printStackTrace ();} RWE%? `   
} M}>q>  
JQqDUd  
frt?*|:  
private void processErrorCode(int nErrorCode) {T9g\F*  
{ ZpyRvDz  
System.err.println("Error Code : " + nErrorCode); tznT*EQr  
} jWz-7BO  
1N &U{#4  
U&NOf;h$  
//停止文件下载 nJnan,`W  
public void siteStop() 7>'F=}6[Y  
{ g=.5*'Xlp  
bStop = true; *HRRv.iQ  
for(int i=0;i<nStartPos.length;i++) lMP7o&  
fileSplitterFetch.splitterStop(); F-6* BUqJ  
?#'qY6 ^  
WBGYk);  
} k)J7) L  
} k1<Py$9"  
//负责部分文件的抓取 {SJLM0=Z  
**FileSplitterFetch.java c?d#Bj ?  
*/ TJ<PT  
package NetFox; E$T#o{pai  
/D  q]=P  
 >Pu*MD;  
import java.io.*; (bw;zNW  
import java.net.*; P|?z1JUd  
R[(,wY_1  
H_Yy.yi  
public class FileSplitterFetch extends Thread { =cQw R:):  
ATU@5,9  
<i5^izg  
String sURL; //File URL [q z6_WOo  
long nStartPos; //File Snippet Start Position aj\'qRrU$  
long nEndPos; //File Snippet End Position ` C1LR,J  
int nThreadID; //Thread's ID R8E<;^?j  
boolean bDownOver = false; //Downing is over L%DL n  
boolean bStop = false; //Stop identical i0P+,U  
FileAccessI fileAccessI = null; //File Access interface "YBA$ef$  
,ZSuo4  
r{btBv  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException V6L_aee}CK  
{ M$)+Uo 2  
this.sURL = sURL; >dM'UpN@  
this.nStartPos = nStart; Wwz>tE  
this.nEndPos = nEnd; PIA&s6U  
nThreadID = id; 3B0%:Jj  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 ;# {x_>M  
} (7IF5g\  
 LCG<  
_YY)-H  
public void run() }LRAe3N%8  
{ I4*N  
while(nStartPos < nEndPos && !bStop) kB 2bT}  
{ sw&Qks? V  
v6GWD}HH,  
Zj JD@,j  
try{ %F7aFvl*  
URL url = new URL(sURL); ^ey\ c1K  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); m} V,+E  
httpConnection.setRequestProperty("User-Agent","NetFox"); IH0Uq_  
String sProperty = "bytes="+nStartPos+"-"; 0C7"*H0 R  
httpConnection.setRequestProperty("RANGE",sProperty); bhI8b/  
Utility.log(sProperty); x\=h^r#w  
myo/}58Nv  
)-9/5Z0v  
InputStream input = httpConnection.getInputStream(); [kXe)dMX8  
//logResponseHead(httpConnection); =FE,G*  
$$4% .J26Z  
 4@5<B  
byte[] b = new byte[1024]; X>CYKRtb  
int nRead; DFiexOb  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) (X8N?tJ  
{ L]V K9qB  
nStartPos += fileAccessI.write(b,0,nRead);  }N[sydL  
//if(nThreadID == 1) 7+c@pEU]  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); kSDV#8 uZ  
} Z` Aiw."|  
(*EN!-/  
K,RIa0)  
Utility.log("Thread " + nThreadID + " is over!"); D,7! /u'  
bDownOver = true; #8`G&S*  
//nPos = fileAccessI.write (b,0,nRead); R 'F|z{8  
} V;z?m)ur  
catch(Exception e){e.printStackTrace ();} ka5>9E  
} X[|>r@Aa!  
} V6!oe^a7'  
7}*5Mir p  
1/gh\9h  
//打印回应的头信息 UeRenp  
public void logResponseHead(HttpURLConnection con) s"'1|^od  
{ q q`Uv U  
for(int i=1;;i++) 8'YL!moG|  
{ /#XO!%=7  
String header=con.getHeaderFieldKey(i); X2{3I\'Ft  
if(header!=null) Q=dR[t>^  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); l`1ZS8 [.  
Utility.log(header+" : "+con.getHeaderField(header)); \h yTcFb  
else koUH>J:  
break; E>ev/6ox  
} g5cR.]oz  
} |h'ugx1iY  
6`yq4!&v  
!=-l760  
public void splitterStop() bNC1[GG[  
{ 9Hu%Z/[!p  
bStop = true; 0+L5k!1D  
} C>;}CH|X  
iU3co|q7  
NO<myN+N  
} DQ~@=%?ni  
. v;Npm2  
.-r 1.'.A  
/* }vL[N~5\  
**FileAccess.java =gj]R  
*//文件访问(定位,写) )FB)ZK;  
package NetFox; 4Qw!YI#40$  
import java.io.*; Jn&(v"_  
|k^X!C0  
Wbc % G8  
public class FileAccessI implements Serializable{ ZF`ckWT:-N  
-AbA6_j  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 6q5V*sJ&  
RandomAccessFile oSavedFile; AXJC&O}`  
long nPos; \UiuJ+  
H: U_k68  
"XH]B  
public FileAccessI() throws IOException TEYbB=.  
{ gC'GZi^  
this("",0); 2n@"|\uHD  
} o~~_>V)W  
5?Bi+fg  
fpzTv3D=I  
public FileAccessI(String sName,long nPos) throws IOException L'c4 i[~s  
{ & z?y  
oSavedFile = new RandomAccessFile(sName,"rw"); u-?&~WA  
this.nPos = nPos; a E#s#Kv   
oSavedFile.seek(nPos); Lrk^<:8;  
} f5O*Njl  
l@^RbF['  
U$-FQRM4K  
public synchronized int write(byte[] b,int nStart,int nLen) jW6@U%[!b  
{ wOOPuCw?  
int n = -1; tkd2AMkh!  
try{ dCc*<S  
oSavedFile.write(b,nStart,nLen);  :&Ul  
n = nLen; I*0 W\Qz@  
} Hv%a\WNS1  
catch(IOException e) & MAIm56~  
{ iA:CPBv_mu  
e.printStackTrace (); b)df V=  
} c  xX  
DO0["O74  
|S.-5CAh4  
return n; Y H?>2u  
} pE=wP/#  
8*|@A6ig  
2Ay2 G-  
} q k !Q2W  
Q@M,:0+cy  
`a<G7  
/* 9m#`56G`  
**SiteInfoBean.java yJr'\(  
*/ SX;FBO(p  
package NetFox; wK,t q  
h5Z%|J>;0  
y<5s)OehG  
public class SiteInfoBean { ]A_)&`"Cb  
z`/v}'d[X  
lfCoL@$6D  
private String sSiteURL; //Site's URL ;KnnAZJ  
private String sFilePath; //Saved File's Path <8H`y(S  
private String sFileName; //Saved File's Name [jafPi(#g  
private int nSplitter; //Count of Splited Downloading File c|I{U[(U  
xOS4J+'s@  
LEk W^Mv  
public SiteInfoBean() ^*Ca+22xO  
{//nSplitter的缺省值为5 af> i  
//default value of nSplitter is 5 b|4h2iuM  
this("","","",5); H1q>UU:  
} AN^;~m^  
K}Aaflq  
(=7e~'DC  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ZZ4W?);;  
{ m+1MoeR  
sSiteURL= sURL; ^d!-IL_  
sFilePath = sPath; fa$ Fo(.  
sFileName = sName; {At1]>  
this.nSplitter = nSpiltter; ]2v31'  
W~gFY#w  
sYeZ.MacU  
} vZ|m3;X  
Bm^vKzp  
{y :/9  
public String getSSiteURL() 7|H !(a'  
{ 2&P'rmFm  
return sSiteURL; fLPB *y6  
} 3:S Ex;d+  
V}3.K\7  
=7Nm= 5@  
public void setSSiteURL(String value) P hn&hRAO  
{ +8v!vuO'  
sSiteURL = value; j_Dx4*v g  
} ( 2<0kqj%  
,u! c|4  
J#bEAK^L,l  
public String getSFilePath() i9+V<'h  
{ YMJ?t"  
return sFilePath; I2D<~xP~2+  
} '|Cs!Zl  
0gxbo  
?e yo2:-$  
public void setSFilePath(String value) ij%\ld9kd  
{ MB:E/  
sFilePath = value; M]eH JZ~v  
} Rh,*tS  
MX  qH  
:fo%)_Jc!  
public String getSFileName() +xB !T1p D  
{ 3_ObCsJ#,  
return sFileName; lO)p  
} t[7YMk  
O[Nc$dc  
wB "&K;t  
public void setSFileName(String value) 4km=KOx[  
{ c7S<ex,  
sFileName = value; f |aO9w   
} / [:@j+n\  
7@MVInV9  
oO!@s`  
public int getNSplitter() YP+0 uZ[g  
{ vlx wt~  
return nSplitter; O Y/QA  
} ss |<\DE+  
omY%sQ{)  
^uC1\!Q1  
public void setNSplitter(int nCount) n omtP }  
{ _q M'm^z5  
nSplitter = nCount; JYs*1<  
} NC|&7qQ  
} |$^,e%bE  
1u 'x|Un  
M'Q{2%:>a  
/* QV7K~qi  
**Utility.java RCnN+b:c  
*/ ,RDxu7iT  
package NetFox;  E~jNUTq  
=^O8 4Cp 6  
3]M YH b  
public class Utility { SO3WOR`3  
M"ZP s   
AZxOq !B  
public Utility() {PWz:\oaD  
{ *~4w%U4T0  
'BcxKqC  
F[ m^(x  
} i8+kc_8#d  
u3w `(3{ <  
//线程睡眠 :/K 'P`JaL  
public static void sleep(int nSecond) Ds$FO}KD{  
{ }|&M@Up  
try{ Y?R;Y:u3Z  
Thread.sleep(nSecond); p;U[cGHC  
} ycIT=AFYqd  
catch(Exception e) @| qnD  
{ `N;u#z  
e.printStackTrace (); L*11hyyk  
} {>pB  
} O=G2bdY{,  
v5RS<?o  
//日志 _LxV)  
public static void log(String sMsg) Yk6fr~b  
{ 's(0>i  
System.err.println(sMsg); WOz dYeeG  
} SG$/v  
kT[]^Jtc  
LPvyfD;Zy  
public static void log(int sMsg) u ,*$n'l]  
{ \/. Of]YQ  
System.err.println(sMsg); 4cTJ$" v  
} 0`3ey*  
} &W)k s  
Z#3wMK~  
fZ 17  
/* yAi#Y3!::  
**TestMethod.java p$0;~1vH  
*/ 6WzE'0Nyr  
package NetFox; VgN`' iC`I  
!c\s)&U7B  
&:nWZ!D  
public class TestMethod { mAX]m1s  
)U`H7\*)  
kS[k*bN0  
public TestMethod() pzCD' !*  
{ ///xx/weblogic60b2_win.exe uZW ?0W  
try{ U]@t\T3W  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 4Q,HhqV'  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); -~p@o1k0  
SiteFileFetch fileFetch = new SiteFileFetch(bean); (TDLT^  
fileFetch.start(); N V^ktln  
} (IAl$IP63s  
catch(Exception e){e.printStackTrace ();} k'xnl"q  
<xOpm8  
8L|rj4z<#  
} 7'xT)~*$4  
7"Zr:|$U  
e*jn7aya  
public static void main(String[] args) ]9]3=;b>  
{ ghx8dX}  
new TestMethod(); lva]jh2  
} ,D  [  
} BB1'B-O  
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