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
  • 11537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
/* 0rxlN [Yp  
**SiteFileFetch.java he8y  
*/ `8\ _ ]w0  
package NetFox; /P<RYA~  
import java.io.*; %L=ro qz  
import java.net.*; _' Xt  
R4 ;^R  
]BP"$rs  
public class SiteFileFetch extends Thread { F]N9ZWn /  
>#Y8#-$zc  
%g^dB M#  
SiteInfoBean siteInfoBean = null; //文件信息Bean k+ 5:fB)z  
long[] nStartPos; //开始位置 "uDLty?*k  
long[] nEndPos; //结束位置 K8XXO"  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 ;}#tm9S;  
long nFileLength; //文件长度 8O qG{jmG  
boolean bFirst = true; //是否第一次取文件 n AQB  
boolean bStop = false; //停止标志 cAM1\3HWT"  
File tmpFile; //文件下载的临时信息 o )GNV  
DataOutputStream output; //输出到文件的输出流 2/ PaXI/Z  
R{NmWj['Mg  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) 'C]zB'H=  
public SiteFileFetch(SiteInfoBean bean) throws IOException _&D I_'5q+  
{ ^SpD)O{  
siteInfoBean = bean; WpP8J1KN[  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); 8b8ui  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); K I  
if(tmpFile.exists ()) Fx~=mYU  
{ cR 4xy26s  
bFirst = false; Q%o ]&Hdn  
read_nPos(); I;qeDCM  
} R44JK  
else NS6#od ZeV  
{ %0YwaxXPn7  
nStartPos = new long[bean.getNSplitter()]; p ~J`}>yo  
nEndPos = new long[bean.getNSplitter()]; w")VcAq  
} RnPJ,Z5s&&  
-_[n2\|we)  
dB ?+-aE  
>M<rr!|  
} Q1mz~r  
d!{,[8&  
&[`p qX  
public void run() |eAl!k  
{ :O-Y67>&  
//获得文件长度 \om$%FUP  
//分割文件 68V66:0  
//实例FileSplitterFetch [h""AJ~t  
//启动FileSplitterFetch线程 vRp =L54z  
//等待子线程返回 V.Dqbv  
try{ g05:A0X#  
if(bFirst) ;JDn1(6  
{ ^*#5iT8/  
nFileLength = getFileSize(); tj;<Z.  
if(nFileLength == -1) NC)Iu  
{ \CM/KrCR  
System.err.println("File Length is not known!"); PaP47>(  
} \|BtgT*$b  
else if(nFileLength == -2) 'b]GcAL  
{ '*MNRduE6  
System.err.println("File is not access!");  ]hpocr  
} 3kx/Q#  
else i=OPl  
{ |!euty ::  
for(int i=0;i<nStartPos.length;i++) 6AKH0t|4  
{ u3(zixb  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); Q@6OIE  
} G4{ zt3{  
for(int i=0;i<nEndPos.length-1;i++) PCF!Y(l  
{ B4bC6$Lg  
nEndPos = nStartPos[i+1]; *>h"}e41  
} U=\ZeYK.  
nEndPos[nEndPos.length-1] = nFileLength; wqx@/--E(  
} "X4OUk  
} c}kZ x1  
A1Ia9@=Mf  
S75wtz)e  
//启动子线程 hn{]Q@(I  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; >0~|iRySi  
for(int i=0;i<nStartPos.length;i++) r&@#,g  
{ 75v 5/5zRn  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Bwj^9J/ob  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), } 1^/[?  
nStartPos,nEndPos,i); 6T! *YrS  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2Vas`/~u~  
fileSplitterFetch.start(); `*mctjSN  
} jq yqOhb4  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), *kY\,r&!P  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); AP' Uc A  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", v]& )+0  
nEndPos = " + nFileLength); XrS.[  
// fileSplitterFetch[nPos.length-1].start(); -^]8w QU  
xQ\/6|  
kE;h[No&K  
//等待子线程结束 89*CoQ  
//int count = 0; 3%{A"^S=}  
//是否结束while循环 I:CnOpR>A  
boolean breakWhile = false; mYJ%gdTpo  
srXGe`VL  
.Qm"iOyM  
while(!bStop) 5+\[x`  
{ qqA(Swe)T  
write_nPos();  }&BE*U8_  
Utility.sleep(500); rCR?]1*Z  
breakWhile = true; (Gr8JpV  
O]>9\!0{  
q4'szDYO2  
for(int i=0;i<nStartPos.length;i++) fw$/@31AP?  
{ ;wwhW|A  
if(!fileSplitterFetch.bDownOver) 8!2NZOZOS  
{ 9\ZlRYnc=  
breakWhile = false; Y f:xM>.%  
break; };6[Byf  
} nAPSs]D  
} {G&*\5W  
if(breakWhile) $"1Unu&P  
break; Aw9se"d  
z )s{>^D  
W+36"?*k3  
//count++; Q]]}8l2  
//if(count>4) <@6K(  
// siteStop(); 3>Y G  
} SxMmy  
Vp{! Ft8>  
A:PQIcR;V  
System.err.println("文件下载结束!"); Wd#r-&!6j  
} /tR@J8pV  
catch(Exception e){e.printStackTrace ();} "| cNY_$&s  
} d 4w+5H" u  
CB_ww=  
ts%XjCN[  
//获得文件长度 7s@%LS  
public long getFileSize() WP[h@#7<  
{ 4>eY/~odq]  
int nFileLength = -1; !)gTS5Rh:  
try{ 6$$4!R-  
URL url = new URL(siteInfoBean.getSSiteURL()); c<-F_+[  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 11t+ a,fM  
httpConnection.setRequestProperty("User-Agent","NetFox"); .RF ijr  
Gx /sJ(  
_^K)>  
int responseCode=httpConnection.getResponseCode(); IaMZPl  
if(responseCode>=400) XgL-t~_  
{ jkCa2!WQ'i  
processErrorCode(responseCode); C^9G \s'  
return -2; //-2 represent access is error c-3-,pyM_T  
} Br^4N9  
HwfBbWHr'  
"#,]` ME;  
String sHeader; YHBH9E/B  
~2u~}v5m7  
1AMxZ (e  
for(int i=1;;i++) 9RA~#S|(T  
{ ~,[-pZ <  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); KG9h rT  
//Utility.log(in.readLine()); r+%:rFeX  
sHeader=httpConnection.getHeaderFieldKey(i); 2..b/  
if(sHeader!=null) /$ Gp<.z  
{ zURxXo/\V  
if(sHeader.equals("Content-Length")) cV^r_E\m  
{ 6[ }~m\cY  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); r9nH6 Md\  
break; v"wxHro  
} !qGER.  
} 4@ EY+p  
else eaLR-+vEB  
break; RhwqAok|lj  
} p1~u5BE7O  
} U9^o"vT  
catch(IOException e){e.printStackTrace ();} z}?*1c  
catch(Exception e){e.printStackTrace ();} L&h@`NPO a  
PNy)TqdRS  
,@I_b  
Utility.log(nFileLength); B-'oB>|  
(=#[om( A  
u\-WArntc  
return nFileLength; $Ro]]NUz|  
} Mn$w_Z?  
K+2k}Hx6J  
1,UeVw/  
//保存下载信息(文件指针位置) v C,53g  
private void write_nPos() p5F=?*[}  
{ iA*^`NMaT  
try{ ^na8d's:  
output = new DataOutputStream(new FileOutputStream(tmpFile)); ]?KTw8j}  
output.writeInt(nStartPos.length); lO^Ly27  
for(int i=0;i<nStartPos.length;i++) y[QQopy4:  
{ NQB a+N  
// output.writeLong(nPos); W)F<<B,  
output.writeLong(fileSplitterFetch.nStartPos); JF{yhx,+ p  
output.writeLong(fileSplitterFetch.nEndPos); U~9Y9qzy,  
} P`z#tDT^"  
output.close(); v9?hcJ=  
} R"@J*\;$T  
catch(IOException e){e.printStackTrace ();} H}v.0R  
catch(Exception e){e.printStackTrace ();} '+?L/|'  
} 6<aZr\Ufg  
4#<r}j12z  
hd+(M[C<9  
//读取保存的下载信息(文件指针位置) `N;}Gf-'  
private void read_nPos() ( X(61[Lu  
{ 5:S=gARz  
try{ tc-pVw:TV  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); t<8vgdD  
int nCount = input.readInt(); Oz8"s4Y7  
nStartPos = new long[nCount]; Z8vMVo  
nEndPos = new long[nCount]; Ug :3)q[O  
for(int i=0;i<nStartPos.length;i++) _FpZc ?=  
{ 8+}yf.`  
nStartPos = input.readLong(); RbOEXH*]  
nEndPos = input.readLong(); cV;<!f+  
} VTS7K2lBvX  
input.close(); 2pr#qh8  
} j:|um&`)  
catch(IOException e){e.printStackTrace ();} d,%e? 8x5  
catch(Exception e){e.printStackTrace ();} #eRrVjbo  
} (RXOv"''=  
~7CQw^"R@  
V$ 8go#5  
private void processErrorCode(int nErrorCode) P:lmQHls+  
{ &Tc:WD  
System.err.println("Error Code : " + nErrorCode); qg7qTF&   
} 'YQVf]4P  
{@1;kG  
s R~D3-  
//停止文件下载 pFB^l|\ ]  
public void siteStop() cy_'QS$W   
{ j 3/ I =  
bStop = true; hk5[ N=  
for(int i=0;i<nStartPos.length;i++) pJg'$iR!/  
fileSplitterFetch.splitterStop(); =1|^) 4M,x  
V(gmC%6%l*  
qu8!fFQjYL  
} R_DstpsT  
} 0iKSUw ps  
//负责部分文件的抓取 2wCSjAWWh(  
**FileSplitterFetch.java JD\yl[ac%  
*/ o*]Tqx  
package NetFox; y nue;*rM  
3VI[*b  
u"$=:GK  
import java.io.*; 7LFJi@*8  
import java.net.*; F.rNh`44  
Xu.Wdl/{Ra  
7lLh4__;`6  
public class FileSplitterFetch extends Thread { A{Kc"s4fO  
<w,NMu"  
dnwTD\),  
String sURL; //File URL RZY[DoF8u  
long nStartPos; //File Snippet Start Position @Sr{6g*I  
long nEndPos; //File Snippet End Position {th=MldJ?  
int nThreadID; //Thread's ID sn!E$ls3O  
boolean bDownOver = false; //Downing is over Q1 t-Z; X  
boolean bStop = false; //Stop identical @p$Nw.{'  
FileAccessI fileAccessI = null; //File Access interface DPWt=IFU  
l1M %   
AfAlDM'  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException g)3HVAT  
{ Vx Vpl@  
this.sURL = sURL; (^{tu89ab  
this.nStartPos = nStart; '3i,^g0?t0  
this.nEndPos = nEnd; =00c1v  
nThreadID = id; ^y,Ex;6o  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 c 5%uiv]  
} X[SdDYMY  
>P<8E2}*  
04j]W]8#  
public void run()  =8o$  
{ 5n0B`A  
while(nStartPos < nEndPos && !bStop) Sux/='  
{ icrcP ~$A  
MQ#nP_i  
_\2Ae\&c  
try{ xS'Kr.S  
URL url = new URL(sURL); h&| S*  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ShIJ6LZ  
httpConnection.setRequestProperty("User-Agent","NetFox"); `MLOf  
String sProperty = "bytes="+nStartPos+"-"; ]Pp}=hcD  
httpConnection.setRequestProperty("RANGE",sProperty); p{vGc-zP .  
Utility.log(sProperty); /!i`K{  
w=QlQ\  
&E?TR A# E  
InputStream input = httpConnection.getInputStream(); Vr ^UEu.w?  
//logResponseHead(httpConnection); Vsj1!}X:  
XsEo tW  
/&i6vWMhP  
byte[] b = new byte[1024]; =#Z+WD-E  
int nRead; o*t4zF&n  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) j&N {j_ M  
{ im&Nkk4n@  
nStartPos += fileAccessI.write(b,0,nRead); : MEB] }  
//if(nThreadID == 1) QM) ob  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos);  5(\H:g\z  
} mx!EuF$I  
8}?w i[T  
2JhE`EVH  
Utility.log("Thread " + nThreadID + " is over!"); X T<SR]  
bDownOver = true; w7%.EA{N  
//nPos = fileAccessI.write (b,0,nRead); 1RgERj  
} jhJ'fI  
catch(Exception e){e.printStackTrace ();} FX  %(<M  
} !jTxMf  
} h}U>K4BJ  
Wt M1nnJp  
B'v~0Kau  
//打印回应的头信息 @kPe/j/[1  
public void logResponseHead(HttpURLConnection con) fq[1|Q  
{ 1xD?cA\vu  
for(int i=1;;i++) K%g_e*"$  
{ | 9 <+!t\  
String header=con.getHeaderFieldKey(i); 1KadT7<0}  
if(header!=null) @$|8zPs  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); "(YfvO+  
Utility.log(header+" : "+con.getHeaderField(header)); M{jJ>S{g  
else 4M )oA|1w  
break; $vLGX>H  
} 98rO]rg  
} RI3GAd  
Gspb\HJ^  
pt%*Y.)az  
public void splitterStop() j0~ dJ#  
{ )tv~N7  
bStop = true; =.]{OT  
} |Kq<}R  
s}<i[hY>  
WjsmLb:5  
} 6ltV}Wt-  
_oE 7<  
=X;h _GQ  
/* m2\[L/W]  
**FileAccess.java v:gdG|n"  
*//文件访问(定位,写) (XNd]G  
package NetFox; (5l'?7  
import java.io.*; 2@Zw#2|]  
pM-mZ/?  
jpkKdQX)  
public class FileAccessI implements Serializable{ jSQM3+`b  
GQ0(lS  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 =bOMtQ]  
RandomAccessFile oSavedFile; 13p.dp`  
long nPos; cz1 m05E  
P#9Pq,I  
=>- W!Of  
public FileAccessI() throws IOException 8I7JsCj  
{ 2<E@f0BVAy  
this("",0); wWVB'MRXB,  
} tkP& =$  
[ e#[j{  
6t{G{ ]  
public FileAccessI(String sName,long nPos) throws IOException 4xF}rm  
{ cp&1yB   
oSavedFile = new RandomAccessFile(sName,"rw"); ge]Z5E(1  
this.nPos = nPos; tP89gN^PA|  
oSavedFile.seek(nPos); }\QXPU{UVd  
} zHD 8 \*  
u`"Y!*[ -  
 N8)]d  
public synchronized int write(byte[] b,int nStart,int nLen) d~KTUgH'<  
{ GA"vJFQ  
int n = -1; 0v|qP  
try{ $+ORq3  
oSavedFile.write(b,nStart,nLen); uMjL>YLq{?  
n = nLen; g: YUuZ  
} H<"EE15  
catch(IOException e) YbF}>1/"  
{ z+c'-!e/  
e.printStackTrace (); n5Mhp:zc,  
} EX@Cf!GjN  
|fY#2\)Yx  
P6)d#M  
return n; oQR?H  
} t!59upbN}3  
.Ms$)1  
Rl'xEtaN  
} xLP8*lvy  
24*3m&fA*K  
t$PJ*F67M  
/* (ZP e{;L.  
**SiteInfoBean.java 1U(!%},  
*/ cR/e Zfl  
package NetFox; Gh}* <X;N  
hyY^$p+  
:BF WX  
public class SiteInfoBean { _TyQC1 d  
iV:\,<8d  
AD >/#Ul  
private String sSiteURL; //Site's URL 9hgIQl  
private String sFilePath; //Saved File's Path 1[-RIN;U8  
private String sFileName; //Saved File's Name f[q_eY  
private int nSplitter; //Count of Splited Downloading File gX(8V*os^  
x[R?hS,0 t  
X;v{,P=J  
public SiteInfoBean() MfraTUxIo/  
{//nSplitter的缺省值为5 212 =+k  
//default value of nSplitter is 5 X7SSTcA   
this("","","",5); 88}04  
} 2<*Yq 8  
mhF@S@  
y2PxC. -  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) &zPM# Q  
{ u1|v3/Q-  
sSiteURL= sURL; qc3?Aplj  
sFilePath = sPath; W+.?J 60  
sFileName = sName; PPh1y;D  
this.nSplitter = nSpiltter; a?)g>e HN  
kdMB.~(K=  
{"0n^!  
} !v*#E{r"g=  
[-\DC*6  
jRp @-S#V  
public String getSSiteURL() sA }X)aP  
{ Cyud)BZvm  
return sSiteURL; G }M!  
} T{ lm z<g  
3]>YBbXvE  
0.#% KfQ  
public void setSSiteURL(String value) 7KtgR=-Lb  
{ !9^GkFR6n  
sSiteURL = value; +EZr@  
} we?t/YB=  
QzYaxNGv  
JV! }"[  
public String getSFilePath() U}{\qs-zt  
{ !zxq9IhWR  
return sFilePath; +PO& z!F  
} tOPk x(  
d%Ku 'Jy  
:$QwOz^N*  
public void setSFilePath(String value) CF5%&B  
{ N]|U-fN\  
sFilePath = value; $-)y59w"  
} 7RgnL<t~:8  
P2)g%$ME  
UL" <V  
public String getSFileName() T{T> S%17~  
{ 1'5 !")r  
return sFileName; * =O@D2g0  
} gKb5W094@  
*oIKddZh  
h#8 {fr)6  
public void setSFileName(String value) s'@@q  
{ ]j(Ld\:L  
sFileName = value; dRTpGz  
} <pUc( tPoz  
j MA%`*r  
_[ `"E'  
public int getNSplitter() 98WJ"f_ #  
{ !v3wl0  
return nSplitter; 4W+nS v  
} yAc}4*;T/  
A3zNUad;  
/zV0kW>N  
public void setNSplitter(int nCount) t aOsC! Bp  
{ ,I[A~  
nSplitter = nCount; 8\Eq(o}7  
} 7M9s}b%?  
} 3*b!]^d:D  
CY9`HQ1  
FD}>}fLv  
/* g/,O51f'  
**Utility.java .]Z,O>N  
*/ $E@ke:  
package NetFox; o6 [i0S  
# /pZ#ny  
#60<$HO:Z  
public class Utility { 4>@-1nt}  
KL*UU,qU  
k?=V?JWY  
public Utility() Iyvl6  
{ SHPZXJ{  
\'N|1!EO|t  
Bb/aeLv  
} jNseD  
#kGxX@0  
//线程睡眠 8%9OB5?F6  
public static void sleep(int nSecond) BcoE&I?[m|  
{ 0b}lwo,|\  
try{ +<I1@C  
Thread.sleep(nSecond); O~&l.>??  
} k)USLA  
catch(Exception e) r,dxW5v.  
{ ^A$~8?f  
e.printStackTrace (); ^SRa!8z$W  
} 1vxh3KS.  
} (.3L'+F  
 ?hpk)Qu  
//日志 XC{(O:EG  
public static void log(String sMsg) }c,}+{q  
{ AuYi$?8|5  
System.err.println(sMsg); I!Za2?  
} -/&6}lD  
VVje|T^{Z  
}fs;yPl,  
public static void log(int sMsg) )+9D$m=P;  
{ Lp*T=]C]  
System.err.println(sMsg); G8?<(.pi@  
} W.,J'  
} efP2 C\  
am05>c9  
`\P:rn95;  
/* Y<.F/iaH  
**TestMethod.java ArU>./)Q  
*/ BmUzsfD  
package NetFox; Xc5[d`]  
:<IW'  
ikRIL2Y  
public class TestMethod { |,&!Q$<un  
RN:#+S(8  
*id|za|:k  
public TestMethod() {UZli[W1  
{ ///xx/weblogic60b2_win.exe LDvF)Eg  
try{ emS+%6U  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); T[q-$8U  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); %dT%r=%Y  
SiteFileFetch fileFetch = new SiteFileFetch(bean); |I+E`,n"b  
fileFetch.start(); L}a3!33)C  
} n8G#TQrAE  
catch(Exception e){e.printStackTrace ();} \a]\j Zb  
,n!xzoX_  
c)6Y.[).  
} lE|T'?/  
Jp-ae0 Ewa  
?s"v0cg+  
public static void main(String[] args) *E)Y?9u"  
{ M9OFK\)  
new TestMethod(); =OZ_\vO  
} H@j^,  
} <7] z'  
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
如果您在写长篇帖子又不马上发表,建议存为草稿
认证码:
验证问题:
10+5=?,请输入中文答案:十五