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
  • 8463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
/* EpW89X  
**SiteFileFetch.java (Sv=R(_s  
*/ :$=]*54`T  
package NetFox; H\%^n<]#  
import java.io.*; "g5<jp  
import java.net.*; y&n-8L_  
*/_$' /q V  
Lo<WK  
public class SiteFileFetch extends Thread { ?]%ZJd  
i,h)V Cc  
xe4`D>LUo  
SiteInfoBean siteInfoBean = null; //文件信息Bean 9^?2{aP%  
long[] nStartPos; //开始位置 ZGw 6Bd_I  
long[] nEndPos; //结束位置 %!\iII  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 +@^FUt=tq  
long nFileLength; //文件长度 {^@vCBE+  
boolean bFirst = true; //是否第一次取文件 (.J6>"K<  
boolean bStop = false; //停止标志 M!`&Z9N  
File tmpFile; //文件下载的临时信息 +xL' LC x  
DataOutputStream output; //输出到文件的输出流 u<U8LR=)V5  
!#Pr'm/,mu  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) Cl8S_Bz  
public SiteFileFetch(SiteInfoBean bean) throws IOException o$p] p9  
{ +;Pkpuu  
siteInfoBean = bean; *b4W+E  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); Z!+n/ D-1  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); Y1wH_!%b  
if(tmpFile.exists ()) %ONU0xtqk  
{ J4]tT pu"K  
bFirst = false; s?JOGu  
read_nPos(); L9]y~[R:  
} %N #A1   
else 7](aPm8  
{ :IX_|8e ^  
nStartPos = new long[bean.getNSplitter()]; ms&6N']  
nEndPos = new long[bean.getNSplitter()]; r0Zj'F_e  
} C14"lB.  
HGao}@'  
/[qLf:rGI  
{,=U]^A  
} ,7I    
"]bOpk T  
oe*fgk/o9  
public void run() >~l^E!<i-u  
{ #[&9~za'"m  
//获得文件长度 (kVxa8 0  
//分割文件 kr\#CW0?  
//实例FileSplitterFetch ! GJT-[  
//启动FileSplitterFetch线程 Q5&|1m Pb  
//等待子线程返回 >l b9j>  
try{ W %1/: _  
if(bFirst) k?}y@$[)  
{ l(pP*2  
nFileLength = getFileSize(); Obx!>mI^6  
if(nFileLength == -1) @rv)J[7Y&  
{ F]L96&  
System.err.println("File Length is not known!"); ?BX}0RWMh7  
} '};mBW4z  
else if(nFileLength == -2) \Ez&?yb/  
{ E#E&z(G2  
System.err.println("File is not access!"); ^U6VJ(58P  
} gg.lajX  
else @8Cja.H  
{ )43z(:<  
for(int i=0;i<nStartPos.length;i++) R].xT-1  
{ C{G;G@/7  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); ;> %wf3e  
} gL &)l!2Y  
for(int i=0;i<nEndPos.length-1;i++) ' ,1[rWyc  
{ N[I ?x5:u  
nEndPos = nStartPos[i+1]; `[&%fTW+  
} ck$>   
nEndPos[nEndPos.length-1] = nFileLength; R"{P#U,HNO  
} 5,BvT>zFY  
} ( m7qc  
h %5keiA  
yb-4[C:i  
//启动子线程 q#F+^)DD [  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; xS;tmc  
for(int i=0;i<nStartPos.length;i++) yuhY )T  
{ Q?bC'147O  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), tqpSir  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ~i]4~bkH2  
nStartPos,nEndPos,i); hGI5^!Cq  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); %NcBq3  
fileSplitterFetch.start(); {Q)sR*d  
} FzF#V=9lP  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), %v0;1m  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ";upu  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", w3;T]R*  
nEndPos = " + nFileLength); |+Xh ^E  
// fileSplitterFetch[nPos.length-1].start(); hbSKlb0d  
y"iK)SH  
4YXp,U  
//等待子线程结束 mln%Rd6u/  
//int count = 0; S3Fj /2Q8  
//是否结束while循环 s6DPb_,  
boolean breakWhile = false; 9fYof  
#+ {%>f  
1I%niQv5t  
while(!bStop) L+lX$k  
{ HP=5 a.  
write_nPos(); YXg^t$  
Utility.sleep(500); )"g @"LJ=  
breakWhile = true; ?z3|^oU~d  
(S_1C,  
t1p[!53(  
for(int i=0;i<nStartPos.length;i++) @vO~'Xxq!  
{ Hn]6re  
if(!fileSplitterFetch.bDownOver) 6ZQ$5PY  
{ D77$aCt  
breakWhile = false; bR J]avR  
break; ^vZu[ m  
} (hIe!"s *  
} >}r 1A  
if(breakWhile) lr[&*v?h  
break; S-79uo  
(\4YBaGd  
/S9n!H:MT  
//count++; &-KQ m20n  
//if(count>4) `a8&7 J(  
// siteStop(); 9 1ec^g  
} 1]aya(  
,w,)n^  
A QPzId*z  
System.err.println("文件下载结束!"); 6-\C?w A  
} ~2UmX'  
catch(Exception e){e.printStackTrace ();} UdFYG^i  
} k~]\kv=  
w69G6G(  
[bEm D  
//获得文件长度 0C717  
public long getFileSize() n*hRlL  
{ MNX-D0`g  
int nFileLength = -1; 6W'2w?qj?4  
try{ CWkAc5  
URL url = new URL(siteInfoBean.getSSiteURL()); ze uSk| O  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); h[]3#  
httpConnection.setRequestProperty("User-Agent","NetFox"); lAAPV  
^3nB2G.ax  
\V*E:_w*  
int responseCode=httpConnection.getResponseCode(); mnH1-}oL  
if(responseCode>=400) >+S* Wtm5  
{ % %QAC4  
processErrorCode(responseCode); Ws[d.El  
return -2; //-2 represent access is error wQU-r|  
} r]%.,i7~8  
'~76Y9mv  
TzrU |D?  
String sHeader; $I a-go2W  
^Y^5 @ x=  
NTSKmCvQG  
for(int i=1;;i++) {6*{P!H  
{ u"zQh|  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); w&}UgtEm  
//Utility.log(in.readLine()); kN* \yH|  
sHeader=httpConnection.getHeaderFieldKey(i); ^j'vM\^`ml  
if(sHeader!=null) ntF#x.1Pm  
{ 0.!Q 4bhD  
if(sHeader.equals("Content-Length")) gR{.0e  
{ q?oJ=]m"  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); g%d&>y?1r  
break; "Oy&6rrr  
} !B&1{  
} G/8G`teAZ  
else po+ 1  
break; |y2cI,&   
} D 3}e{J8  
} |Vc:o_n7  
catch(IOException e){e.printStackTrace ();} )h(yh50 B  
catch(Exception e){e.printStackTrace ();} g$S<_$Iey  
 \4&FW|mx  
Gp))1b';  
Utility.log(nFileLength); ,lw<dB@7"5  
XJf1LGT5  
/J'dG%  
return nFileLength; A\<WnG>xjP  
} Y&DC5T]  
fpvzx{2  
E %> ){Y)  
//保存下载信息(文件指针位置) _:l<4u !  
private void write_nPos() J""N:X!1  
{ q,eXH8 x  
try{ ;AgXl%Q  
output = new DataOutputStream(new FileOutputStream(tmpFile)); \J^|H@;(@  
output.writeInt(nStartPos.length); QX 393v!  
for(int i=0;i<nStartPos.length;i++) V~qlg1h  
{ ZBfB4<M9xS  
// output.writeLong(nPos); zXg/.z]  
output.writeLong(fileSplitterFetch.nStartPos); qbdv  
output.writeLong(fileSplitterFetch.nEndPos); <S M%M?  
} qxglA*/ [  
output.close(); -%)8=  
} rDWqJ<8  
catch(IOException e){e.printStackTrace ();} W= \gPCo  
catch(Exception e){e.printStackTrace ();} `'<&<P  
} (6\ H~  
[+v}V ,jb  
D`uOBEX  
//读取保存的下载信息(文件指针位置) Nh|QYxOP  
private void read_nPos() s&*s9F  
{ `=f1rXhI+1  
try{ '|N9xL m  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); #$9rH 2zd  
int nCount = input.readInt(); o*WI*Fb'  
nStartPos = new long[nCount]; a"0'cgB}  
nEndPos = new long[nCount]; v:$Y |mh  
for(int i=0;i<nStartPos.length;i++) jP|(y]!  
{ TJp0^&Q  
nStartPos = input.readLong(); :j0r~*z-  
nEndPos = input.readLong(); *S4*FH;8  
} {pNf& '  
input.close(); T5di#%: s  
} 2*1s(Jro  
catch(IOException e){e.printStackTrace ();} ~2*8pb 4  
catch(Exception e){e.printStackTrace ();} $:MO/Su z{  
} B%Sp mx8  
j8gi/07l  
1~#p3)B  
private void processErrorCode(int nErrorCode) - '5OX/Szq  
{ /.aDQ>  
System.err.println("Error Code : " + nErrorCode); +EBoFeeIG  
} onj:+zl  
x?|   
P9D'L{yS/x  
//停止文件下载 Wc)f:]7  
public void siteStop() ;1 02ddRV  
{ (P N!k0Y  
bStop = true; 0Ie9T1D=  
for(int i=0;i<nStartPos.length;i++) .v:K`y;f\(  
fileSplitterFetch.splitterStop(); fX2PteA0qX  
S?_ ;$Cn  
OVm $  
} pJE317 p'  
} 4!dN^;Cb  
//负责部分文件的抓取 r:Xui-  
**FileSplitterFetch.java L?n*b  
*/ ~IKPi==@,  
package NetFox; G&Sp }  
cEd!t6Z  
]='E&=nc  
import java.io.*; {<- BU[H  
import java.net.*; O5Xu(q5+  
=/rIXReY  
w(9.{zF|vQ  
public class FileSplitterFetch extends Thread { +cVnF&@$  
j5:{H4?  
{>c O&eiCt  
String sURL; //File URL ivbuS-f =r  
long nStartPos; //File Snippet Start Position O`hOVHD Q  
long nEndPos; //File Snippet End Position jo4*,B1x  
int nThreadID; //Thread's ID @M-+-6+  
boolean bDownOver = false; //Downing is over 2|)3Ly9  
boolean bStop = false; //Stop identical FPu"/4v&  
FileAccessI fileAccessI = null; //File Access interface =,~h]_\_  
 98os4}r  
D`lTP(] y  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException /)PD+18  
{ )[>b7K$f  
this.sURL = sURL; 8 ]N+V:  
this.nStartPos = nStart;  mq?5|`  
this.nEndPos = nEnd; RYaf{i`  
nThreadID = id; <Dw`Ur^X5  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 !RnO{FL  
} p_jDnb#  
!ldb_*)h  
zZ|Si  
public void run() 1;[\xqJ  
{ qlSc[nEk  
while(nStartPos < nEndPos && !bStop) DH_Mll>  
{ @l^=&53T  
u5 EHzoq  
XX,iT~+-  
try{ 0*"auGuX  
URL url = new URL(sURL); XnQo0 R.PW  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 0f 1Lu) 2  
httpConnection.setRequestProperty("User-Agent","NetFox"); pCNihZ~  
String sProperty = "bytes="+nStartPos+"-"; M ,8r{[2  
httpConnection.setRequestProperty("RANGE",sProperty); ":*PC[)W  
Utility.log(sProperty); ;jTP|q?|{  
++:vO  
B8_ w3;x  
InputStream input = httpConnection.getInputStream(); ubIGs| p2c  
//logResponseHead(httpConnection); Cd#>,,\z  
92GO.xAD?  
ho_;;y  
byte[] b = new byte[1024]; 5yO6szg  
int nRead; j3rBEQ,R  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) OZ1+`4 v  
{ O edL?4  
nStartPos += fileAccessI.write(b,0,nRead); tH<v1LEZN  
//if(nThreadID == 1) pAYH"Q6~)I  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); dvk? A$  
} tqIz$84G  
. oUaq|O  
*tjE#TW  
Utility.log("Thread " + nThreadID + " is over!"); qbkvwL9  
bDownOver = true; @M?N[LG  
//nPos = fileAccessI.write (b,0,nRead); a8-2:8Su  
} t#~r'5va  
catch(Exception e){e.printStackTrace ();} !Ljs9 =UF  
} #:Di1I9<O7  
} su(y*187A  
0 iW]#O/  
&eT)c<yhyK  
//打印回应的头信息 jpqq>Hbg_  
public void logResponseHead(HttpURLConnection con) I;L $Nf{v  
{ bh?Vufd%)  
for(int i=1;;i++) uYS?# g  
{ =8j;!7 p  
String header=con.getHeaderFieldKey(i); pc5-'; n  
if(header!=null) TdP_L/>|J  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); E) >~0jv  
Utility.log(header+" : "+con.getHeaderField(header)); W?G4\ubM3<  
else abUn{X+f~  
break; ( =->rP  
} wYhWRgP  
} y>u+.z a|  
gy _86y@  
8<k0j&~J  
public void splitterStop() V# |#% 8  
{ R)t"`'6|  
bStop = true; dZRz'd  
} f 5_n2  
L._I"g5 H9  
J /'woc  
} q,2]]K7y  
`|i #)  
B}gi /  
/* nbw&+dcJ8  
**FileAccess.java t/_w}  
*//文件访问(定位,写) Fm{Ri=X<:  
package NetFox; f!*b8ND^R  
import java.io.*; 5SK{^hw  
?};}#%971  
U n2xZ[4  
public class FileAccessI implements Serializable{ =+97VO(w]G  
NDU,9A.P  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 C+,;hj  
RandomAccessFile oSavedFile; #18H Z4N  
long nPos; xzy7I6X  
,Vt7Kiu  
'  G-]>  
public FileAccessI() throws IOException a |32Pn  
{ Rs{L  
this("",0); Qwk  
} gCgMmD=AZ  
18Vtk"j  
>c\'4M8Cz  
public FileAccessI(String sName,long nPos) throws IOException i=reJ(y-  
{ ]~87v  
oSavedFile = new RandomAccessFile(sName,"rw"); xg'z_W  
this.nPos = nPos; ME1lQ7E4B  
oSavedFile.seek(nPos); "4H&wHhT!  
} 3ZU`}  
\S}&QV  
&m`1lxT  
public synchronized int write(byte[] b,int nStart,int nLen) vML01SAi  
{ ,2[laJ  
int n = -1; Tm_AoZH  
try{ sZPPS&KoP3  
oSavedFile.write(b,nStart,nLen); /lm;.7_J+  
n = nLen; K-)_1  
} q>%KIBh(  
catch(IOException e) wtetB')yD  
{ n%3rv?m7  
e.printStackTrace (); 2JYyvJ>  
} /Bid:@R  
NUEy0pLw  
OTL=(k  
return n; {~k /xM.-  
} bec n$R  
$f*N  
ln'7kg  
} &'N{v@Oi)  
d%81}4f:  
c7q1;X{:  
/* %(Nu"3|$K=  
**SiteInfoBean.java ._~_OVU  
*/ qWHH% L;  
package NetFox; /0d_{Y+9  
vO%n~l=  
p8oOm>B96n  
public class SiteInfoBean { R(kr@hM  
_,=A\C_b@  
@~U: |h  
private String sSiteURL; //Site's URL 92WvD  
private String sFilePath; //Saved File's Path :qc@S&v@]  
private String sFileName; //Saved File's Name U GQ{QH  
private int nSplitter; //Count of Splited Downloading File 8*H-</ =  
vmvk  
m7zen530  
public SiteInfoBean() rF2`4j&!  
{//nSplitter的缺省值为5 x %L2eXL  
//default value of nSplitter is 5 k8F<j)"  
this("","","",5); I0(BKMp&  
} (8qMF{  
5CueD]  
>:Na^+c  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Y]P'; C_eP  
{ wP/&k`HQ#i  
sSiteURL= sURL; 'LpJ:Th  
sFilePath = sPath; `g<@F^x5  
sFileName = sName; 7u6o~(  
this.nSplitter = nSpiltter; Ha1E /b]K  
84DneSpHsp  
ZvpcjP  
} sczN0*w&C  
,u#uk7V  
=GL}\I  
public String getSSiteURL() j5|_SQOmt  
{ LUl6^JU  
return sSiteURL; |o6 h:g  
} XpdDIKMmE  
#25Z,UU  
6B)(kPW  
public void setSSiteURL(String value) =\B{)z7@6D  
{ 9 #TzW9  
sSiteURL = value; ,G!M?@Q  
} ,3.E]_3 xX  
n`2 d   
3xxQL,FV  
public String getSFilePath() pzbR.L}'D  
{ 8V>j-C  
return sFilePath; .mn`/4  
} 53J!iNnXT6  
WW{5[;LYiB  
:.'<ndM  
public void setSFilePath(String value) PBbJfm  
{ yQ}$G ,x  
sFilePath = value; l)[\TD  
} n1 =B  
q&Y'zyHLP  
QM2Y?."#  
public String getSFileName() ;n%SjQ'%  
{ 8>x!n/z)  
return sFileName; '3 w=D )  
} u=z$**M^  
:6S!1roi  
1 !bODd  
public void setSFileName(String value) Y (x_bJ  
{ % obR2%  
sFileName = value; .+MJ' bW  
} <+o-{{E[  
jl;_lcO  
&PaqqU.  
public int getNSplitter() dF:@BEo  
{ QO0}-wZR  
return nSplitter; ']Gqa$(YC  
} k"&l o h  
'DO^($N  
_ui03veA1  
public void setNSplitter(int nCount) 5XySF #  
{ `E+)e?z  
nSplitter = nCount; f uQbDb&  
} $h`(toTyF  
} k"\%x =#  
T$T:~8tK3  
Aayh'xQ  
/* gKeqf-UWKJ  
**Utility.java 3sIW4Cs7)U  
*/ MGze IrV  
package NetFox; usH9dys,  
I_6NY,dF  
,yus44w[  
public class Utility { M.$Li#So,  
g@wF2=  
qYR $5  
public Utility()  N-`Vb0;N  
{ "RMBV}<T  
>/mi#Y6  
l*>t@:2J  
} (|)`~z  
c[\ :^w^I6  
//线程睡眠 4 YDK`:4I~  
public static void sleep(int nSecond) ~XN--4%Q  
{ =}>wxO  
try{ x=T`i-M  
Thread.sleep(nSecond); ma9q?H#X  
} [ -"o5!0<  
catch(Exception e) i!+D ,O  
{ BLZ#vJR  
e.printStackTrace (); 6r! Y ~\@  
} 4 AZ~<e\  
} T Po%zZo  
z%$ E6Im  
//日志 oFM\L^Y?$$  
public static void log(String sMsg) psyxNM=dN#  
{ 7ksh%eV  
System.err.println(sMsg); IhnHNY]<g  
} LOQoi8j  
c.-h'1  
A}WRpsA9  
public static void log(int sMsg) _a1 =?  
{ 1c_gh12  
System.err.println(sMsg); q9fCoz  
} ' QGacV   
} B?A c  
KwK[)Cvv  
x{{QS$6v  
/* !$Aijd s5  
**TestMethod.java ]T|9>o!  
*/ Xou1X$$z  
package NetFox; [p[nK=&r  
j(^ot001%v  
{6{y"8  
public class TestMethod { wI.i\ S  
ASmMj;>UM  
f0p+l -iEv  
public TestMethod() Z0&^U#]  
{ ///xx/weblogic60b2_win.exe  7'u<)V  
try{ T'\B17 :*  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); RrrW0<Ed  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Z|;<:RKWY  
SiteFileFetch fileFetch = new SiteFileFetch(bean); {Hncm  
fileFetch.start(); ?_mcg8A@@*  
} :$k':0 n  
catch(Exception e){e.printStackTrace ();} J-*&&  
OQzJRu)mF#  
qu]ch&"?U  
} }$M 2XF  
o?n lnoe  
r @C2zF7  
public static void main(String[] args) ZeewGa^r  
{ zogtIn)  
new TestMethod(); 1d/-SxhZ  
} *Q2;bmIc  
} ~\= VSwJ  
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
温馨提示:欢迎交流讨论,请勿纯表情、纯引用!
认证码:
验证问题:
3+5=?,请输入中文答案:八 正确答案:八