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
  • 7648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
/* IFF3gh42.  
**SiteFileFetch.java B7nm7[V  
*/ Ct9*T`Gl  
package NetFox; j79$/ Ol  
import java.io.*; C: a</Sl  
import java.net.*; t3;QF  
Hp-vBoEk  
' 8UhYwyr  
public class SiteFileFetch extends Thread { to;cF6X  
d8/KTl  
,IQ%7*f;O_  
SiteInfoBean siteInfoBean = null; //文件信息Bean txe mu *  
long[] nStartPos; //开始位置 %51HJB}C]  
long[] nEndPos; //结束位置 AR5)Uw s  
FileSplitterFetch[] fileSplitterFetch; //子线程对象 N##- vV  
long nFileLength; //文件长度 )r:gDd#/X  
boolean bFirst = true; //是否第一次取文件 ?F@X>zR2  
boolean bStop = false; //停止标志 OT}^dPQe  
File tmpFile; //文件下载的临时信息 +&8'@v$  
DataOutputStream output; //输出到文件的输出流 1Et{lrgh f  
MF.$E?_R  
//负责整个文件的抓取,控制内部线程(FileSplitterFetch类) \$D41_Wt|  
public SiteFileFetch(SiteInfoBean bean) throws IOException ;F\sMf{  
{ rZG6}<Hx  
siteInfoBean = bean; qwHP8GU  
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath())); 'V(9ein^Q  
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info"); [fr!J?/@  
if(tmpFile.exists ()) ny[\yj4F  
{ Y EhPAQNj  
bFirst = false; ak]H|D" 9  
read_nPos(); >Gxh=**F  
} %vjfAdC  
else c"^g*i2&0  
{ xX2/uxi8  
nStartPos = new long[bean.getNSplitter()]; k= oCpXq^  
nEndPos = new long[bean.getNSplitter()]; 5D`!Tu3  
} R(<_p"9(  
6gJc?+  
gL6.,4q+1  
='\E+*[$I  
} .*g^ i`  
*|&&3&7  
.Sjg  
public void run() WO"<s{v  
{ gatxvR7H  
//获得文件长度 h9WyQl7  
//分割文件 L$ ZZ]?7j  
//实例FileSplitterFetch %2EHYBQjN  
//启动FileSplitterFetch线程 LFPYnK  
//等待子线程返回 i$S*5+  
try{ t Ai?Bjo  
if(bFirst) SoL"M[O  
{ .+dego:  
nFileLength = getFileSize(); =z +iI;  
if(nFileLength == -1) }R2afTn[;  
{ #tlhH\Pr[  
System.err.println("File Length is not known!"); q;H5S<]/  
} 7xjihl3  
else if(nFileLength == -2) n% ={!WD  
{ fIm=^}?fwK  
System.err.println("File is not access!"); W3-g]#\?  
} }-15^2  
else ,3FG' q2  
{ 5r(Y,m"?  
for(int i=0;i<nStartPos.length;i++) &L4>w.b"N  
{ SyCa~M!}>  
nStartPos = (long)(i*(nFileLength/nStartPos.length)); 95hdQ<W  
} IltU6=]"l  
for(int i=0;i<nEndPos.length-1;i++) jK-usn  
{ @sLB _f  
nEndPos = nStartPos[i+1]; DyPb]Udb:  
} QN OA66  
nEndPos[nEndPos.length-1] = nFileLength; K{[N.dX(  
} Xo~kB)|,  
} pQ9~^  
A!fRpN  
TrmrA$5f  
//启动子线程 WTQd}f  
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; <<[\ Rv  
for(int i=0;i<nStartPos.length;i++) -JfO} DRI  
{ [eO6 H2@=z  
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), XZ[3v9?&n  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), [Cf{2WB:7  
nStartPos,nEndPos,i); >19j_[n@VC  
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); V( SRw  
fileSplitterFetch.start(); l6k.`1.In  
} N2e]S8-  
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), P~7p~ke  
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); (`FY{]Wz!  
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", - {|  
nEndPos = " + nFileLength); &Y|AX2KUC  
// fileSplitterFetch[nPos.length-1].start(); EK<ly"S.  
NGOyd1$7N  
?D S|vCae  
//等待子线程结束 2kVQ#JyuRI  
//int count = 0; hxx`f-#=  
//是否结束while循环 oiNt'HQ2/  
boolean breakWhile = false; V}+Ui]ie|I  
#JW~&;  
(GXFPEH8  
while(!bStop) T$Rj/u t1  
{ K1[(% <Gp  
write_nPos(); !S5_+.U#  
Utility.sleep(500); 2;&!]2vo$  
breakWhile = true; A_JNj8<6r  
w>uo-88  
V { yk  
for(int i=0;i<nStartPos.length;i++) F=r`'\JV[  
{ f4r)g2Zb[  
if(!fileSplitterFetch.bDownOver) h^ =9R6im  
{ RqRyZ*n  
breakWhile = false; +DA ,|~k_  
break; R1NwtnS  
} &1$|KbmV4  
} 7bC)Co#:   
if(breakWhile) { K *  
break; 9>hK4&m^  
TxXX}6  
m. "T3K  
//count++; El4SL'E@  
//if(count>4) BhC>G2 ^7  
// siteStop(); P1A5Qq  
} C!s !j  
w^wh|'u^_@  
J^)=8cy  
System.err.println("文件下载结束!"); "=vH,_"Ql  
} y?.l9  
catch(Exception e){e.printStackTrace ();} NB?y/v  
} z{ MO~d9  
yjj)+eJ(Q  
$|pD}  
//获得文件长度 )G=hgqy  
public long getFileSize() w-?|6I}T  
{  ua] ?D2  
int nFileLength = -1; ry!0~ir  
try{ zaMKwv}BR  
URL url = new URL(siteInfoBean.getSSiteURL()); YH/3N(],  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); VAet!H+]  
httpConnection.setRequestProperty("User-Agent","NetFox"); yy#4DYht  
APM!xX=N  
2}jC%jR2  
int responseCode=httpConnection.getResponseCode(); xI(Y}>  
if(responseCode>=400) *#g[ jl4  
{ Ft^+P*  
processErrorCode(responseCode); \:|"qk  
return -2; //-2 represent access is error @w{"6xc%a  
} o0\d`0-el  
2V)qnMxAZJ  
"Iwd-#;$;  
String sHeader; i*2l4  
~fR-cXj"  
UhVJ !NrT  
for(int i=1;;i++) Xw |6 #^  
{ * J|]E(  
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); aYd`E4S+  
//Utility.log(in.readLine()); kcyT#'=j  
sHeader=httpConnection.getHeaderFieldKey(i); X;%*+xQ^  
if(sHeader!=null) V.^Z)iNf^  
{ GG$&=.$  
if(sHeader.equals("Content-Length")) V/W{d[86G  
{ 0$\ j  
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); I4\ c+f9  
break; Qa-~x8]  
} E{W(5.kb;i  
} ]?A-D,!(  
else F  uJ=]T  
break; SJXP}JB_  
} Mv#\+|p 1x  
} :1,xse  
catch(IOException e){e.printStackTrace ();} wS}Rl}#Oh?  
catch(Exception e){e.printStackTrace ();} TU}. /b@F  
8PtX@s43\  
I4%25=0?  
Utility.log(nFileLength); ]#t5e>o|  
p4M7BK:nf  
`;H3['~$  
return nFileLength; iyr'9BA  
}  3JcI}w  
TSHH=`cx  
Z&Ao;=Gp1  
//保存下载信息(文件指针位置) A!.* eIV|  
private void write_nPos() xA {1XS}  
{ )!jX$bK  
try{ &p6^    
output = new DataOutputStream(new FileOutputStream(tmpFile)); +U= !svE  
output.writeInt(nStartPos.length); RuuXDuu:VL  
for(int i=0;i<nStartPos.length;i++) Zg~6  
{ #;~dA  
// output.writeLong(nPos); &RbT&  
output.writeLong(fileSplitterFetch.nStartPos); 'Bb@K[=s  
output.writeLong(fileSplitterFetch.nEndPos); l5fF.A7TT  
} F}dq~QCzw  
output.close(); $mZpX:7/u8  
} CY i{WV(:  
catch(IOException e){e.printStackTrace ();} bf&k:.v'8  
catch(Exception e){e.printStackTrace ();} c`x[C  
} /!HFi>   
4,P!D3SH  
StWF66u34&  
//读取保存的下载信息(文件指针位置) IWD21lS  
private void read_nPos() TVEFZ\p<A  
{ Y~+`F5xX<  
try{ F\( 7B#  
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ;1[Lwnm  
int nCount = input.readInt(); k}r)I.Lp  
nStartPos = new long[nCount]; 9HJA:k*k|  
nEndPos = new long[nCount]; 8w]>SEGFs  
for(int i=0;i<nStartPos.length;i++) R4P$zB_<2  
{ DA -W =Cc  
nStartPos = input.readLong(); O| zLD  
nEndPos = input.readLong(); /aHx'TG  
} 5'hQ6i8  
input.close(); wc7F45l4  
} Q]NGd 0J  
catch(IOException e){e.printStackTrace ();} ^tY$pPA  
catch(Exception e){e.printStackTrace ();} 96.Vm*/7  
} 2*1FW v  
D|rcSa.M  
<"rckPv_H  
private void processErrorCode(int nErrorCode) kx_PMpc  
{ i1JWdHt  
System.err.println("Error Code : " + nErrorCode); jXALN  
} dgsD~.((A  
X*Dt<i};v  
gdVajOAu  
//停止文件下载 GtNGrJU  
public void siteStop() `.8#q^  
{ k9iXVYQ.;r  
bStop = true; *N|s+  
for(int i=0;i<nStartPos.length;i++) y/}ENUGR  
fileSplitterFetch.splitterStop(); a{%]X(';  
Y^P'slY{%  
b/g"ws_  
} ]p sx\ZMa  
} e:H9!  
//负责部分文件的抓取 UZq1qn@+  
**FileSplitterFetch.java jQ[M4)>_k`  
*/ +HxL>\  
package NetFox; Wr+1G 8  
RIQw+RG >  
,) JSX o  
import java.io.*; 2r~&+0sBP  
import java.net.*; =-GHs$u%f  
N2_9V~!  
YDMimis\H5  
public class FileSplitterFetch extends Thread { Jxy94y*  
b 7%O[  
N>J"^GX  
String sURL; //File URL ]A2l%V_7  
long nStartPos; //File Snippet Start Position zrJ/Fs+s  
long nEndPos; //File Snippet End Position |vY0[#E8&  
int nThreadID; //Thread's ID s*0PJ\E2  
boolean bDownOver = false; //Downing is over }|7y.*  
boolean bStop = false; //Stop identical i`2X[kc  
FileAccessI fileAccessI = null; //File Access interface |,wp@)e6h  
vHz]-Q-|9  
30Z RKrW"~  
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 8Qg,UX  
{ )|@ H#kv?  
this.sURL = sURL; [# '38  
this.nStartPos = nStart; @]0;aZ{3  
this.nEndPos = nEnd; B "z`X!\  
nThreadID = id; C'c9AoE5>  
fileAccessI = new FileAccessI(sName,nStartPos);//定位 p#V h[UTl^  
} HX3R@^vo  
<Y9xHn&  
Q/ ,j v5  
public void run() 79svlq=  
{ W l+[{#  
while(nStartPos < nEndPos && !bStop) uKcwVEu  
{ #+- /0{HT  
Aey*n=V4#F  
Evn=3Tw  
try{ :uD*Q/  
URL url = new URL(sURL); Vp'Zm:  
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); :2KLziO2  
httpConnection.setRequestProperty("User-Agent","NetFox"); >_4Ck{^d#  
String sProperty = "bytes="+nStartPos+"-"; ?T(>!m  
httpConnection.setRequestProperty("RANGE",sProperty); u0@i3Po  
Utility.log(sProperty); ZE*m;  
~$8t/c  
hF!t{ Lf3  
InputStream input = httpConnection.getInputStream(); !P&F6ViO=  
//logResponseHead(httpConnection); !)(c_ uz  
%`P6a38j  
hK,e<?N^  
byte[] b = new byte[1024]; m"<Sb,"x!  
int nRead; ORV~F0d<  
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) SJtQK-%wK>  
{ |@x^5Ab$T  
nStartPos += fileAccessI.write(b,0,nRead); 0 7CufoI  
//if(nThreadID == 1) |-HV@c]  
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 5;5DEMe  
} ]i-peBxw  
`;ofQz4  
p. eq N  
Utility.log("Thread " + nThreadID + " is over!"); 3f2%+2Zjt,  
bDownOver = true; ER O'{nT&  
//nPos = fileAccessI.write (b,0,nRead); )5}=^aqd  
} W -Yv0n3  
catch(Exception e){e.printStackTrace ();} g{zvks~it  
} D~~&e<v'1  
} ] {r*Z6bs  
|=^p`CT  
@{_L38. Nw  
//打印回应的头信息 zoV4Gl  
public void logResponseHead(HttpURLConnection con) P,x'1 `k~  
{ TX96 ^EoH  
for(int i=1;;i++) Zxm Mw  
{ Zz<k^  
String header=con.getHeaderFieldKey(i); hpD\,  
if(header!=null) y\DR,$Py  
//responseHeaders.put(header,httpConnection.getHeaderField(header)); hE41$9?TJ  
Utility.log(header+" : "+con.getHeaderField(header)); F_9eju^|  
else El;\#la  
break; BULf@8~(  
} (cX;a/BR  
} k !S0-/ h  
=/Ob kVYf  
DD3.el}6a  
public void splitterStop() wo($7'.@  
{ c/Fy1Lv\  
bStop = true; l,n0=Ew  
} jP?YV  
T5; zgr  
)~ {T  
} QxRT%;'Zh]  
\Kp!G1?_AY  
lWr{v\L'  
/* $TON`+lB  
**FileAccess.java qB57w:J  
*//文件访问(定位,写) ra L!}  
package NetFox; =.=4P~T&  
import java.io.*; V _(L/6  
Lo^0VD!O  
Yv?nw-HM  
public class FileAccessI implements Serializable{ '- >%b  
>h^CC*&'pw  
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 u^DfRd&P0  
RandomAccessFile oSavedFile; yrp5\k*{y  
long nPos; hk =nXv2M  
D# ZzhHHP  
;GW[Yw>Rz  
public FileAccessI() throws IOException O)y|G%O  
{ J<g$hk  
this("",0); !^{0vFWE  
} D00I!D16  
B?BB  
m0}Pq{ g  
public FileAccessI(String sName,long nPos) throws IOException B$R"Ntp  
{ {E6M_qZ  
oSavedFile = new RandomAccessFile(sName,"rw"); xbbQ)sH&m  
this.nPos = nPos; y0!-].5UH  
oSavedFile.seek(nPos); d5zv8?|X+  
} snPM&  
xq`mo  
OF[y$<jM  
public synchronized int write(byte[] b,int nStart,int nLen) MKqMH,O  
{ T5* t~`bfU  
int n = -1; !S0$W?*  
try{ K4 \{G  
oSavedFile.write(b,nStart,nLen); 7jss3^.wA  
n = nLen; dQX<X}  
} 5*M3sN  
catch(IOException e) >?-etl  
{ x$:>W3?T=^  
e.printStackTrace (); C`qo  
} #&fi[|%X$  
uw!w}1Y]}2  
J7Z`wjX1  
return n; L5(7;  
} RO>3U2  
uY{zZ4iw  
5c(mgEvq  
} Un [olp  
s"hSn_m  
W6~aL\[  
/* e70#"~gt[  
**SiteInfoBean.java _ELuQ>zM]+  
*/ MIV<"A  
package NetFox; L="ipM:Z  
h(M_ K  
^^q9+0@  
public class SiteInfoBean { U/hf?T;  
.[%^~q7  
UH8q:jOi  
private String sSiteURL; //Site's URL Y[_{tS#u  
private String sFilePath; //Saved File's Path pD^7ZE6  
private String sFileName; //Saved File's Name WJ%4IaT  
private int nSplitter; //Count of Splited Downloading File ,]A|z ~q  
DC9\Sp?  
<1t.f}}uX  
public SiteInfoBean() T0:%,o  
{//nSplitter的缺省值为5 I&2)@Zw  
//default value of nSplitter is 5 }XOTK^YA  
this("","","",5); C)x>/Qr~  
} 47S1mxur  
^("23mhfJ  
7T\LYDT  
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) gu~JB  
{ rM?O2n  
sSiteURL= sURL; v'0WE  
sFilePath = sPath; 9'$\GN{0  
sFileName = sName; 0m3:!#\  
this.nSplitter = nSpiltter; mP!=&u fcU  
kGz0`8U Ru  
s5`CV$bz  
} !hMD>B2Z  
eo#2n8I>=1  
j{8;5 ?x  
public String getSSiteURL() !?AgAsSmc  
{ U?@ s`.  
return sSiteURL; Ff eX;pi  
} D8OW|wVE  
71S~*"O0f  
<0EVq8h  
public void setSSiteURL(String value) *5e"suS2  
{ UyFvj4SU  
sSiteURL = value; g2Hz[C(  
} A7`+XqG  
2F}D?] A  
ec8 iZ8h8  
public String getSFilePath() n]%T>\gw  
{ 5`_UIYcI  
return sFilePath; '' Pu  
} U4$}8~o4  
TnuaP'xZ  
g!QX#_~Il  
public void setSFilePath(String value) Kia34 ~W  
{ =&_Y=>rA]0  
sFilePath = value; A$JL"~R  
} .RazjXAY  
j7(S=  
E Pd9'9S  
public String getSFileName() rtjUHhF  
{ s%bm1$}  
return sFileName; k<Y}BvAYB  
} _?}[7K!~d  
R!+_mPb=Q*  
-XJXl}M.  
public void setSFileName(String value) a< E\9DL  
{ M~?2g.o'D  
sFileName = value; jqzG=/0~{  
} 6"o,)e/z  
De<kkR{4  
,(;TV_@$  
public int getNSplitter() 8wf[*6VwV  
{ kndN} Vq  
return nSplitter; PHxU6UPqy  
} (kYwD  
J<9;Ix8R  
ov 'g'1}  
public void setNSplitter(int nCount) >h Rq  
{ t}Q PPp y  
nSplitter = nCount; \yE*nZ  
} &6@# W]_  
} zObrp  
# 0* oj/  
JS!`eO/8  
/* -"CXBKHb  
**Utility.java E,}(jAq7  
*/ %a=^T?8  
package NetFox; it.'.aK4  
b(HbwOt ~3  
K ; e R)  
public class Utility { Y00hc8<  
"y7IH GJ\3  
%.rVIc"  
public Utility() .4cV X|T  
{ C"*8bVx]$n  
?*/1J~<(@  
9F "^MzZ  
} my}l?S[2d@  
t_"]n*zk1  
//线程睡眠 L; o$vI~U,  
public static void sleep(int nSecond) 1$S`>M%a  
{ 2v\<MrL  
try{ H/^t]bg,  
Thread.sleep(nSecond); sK/Z 'h{|  
} Qn!KL0w  
catch(Exception e) khb/"VYd  
{ t%fcp  
e.printStackTrace (); (7*((  
} haSC[[o=  
} ]Vm:iF#5P  
"nA~/t=  
//日志 8dUP_t~d#q  
public static void log(String sMsg) OnND(YiX  
{ 2EC<8}CG  
System.err.println(sMsg); B1k;!@@1 4  
} }8Yu"P${Y  
V6!1(|  
`L m9!?  
public static void log(int sMsg) 'E)g )@^  
{ i `7(5L~`  
System.err.println(sMsg); v\G+t2{  
} |ERf3  
} VUUE2k;^  
o^3X5})sv  
v/GZByco>  
/* iO dk)  
**TestMethod.java M `49ydh&  
*/ O"ebrv  
package NetFox; >|rU*+I`  
V'8Rz#Gc5  
}G ^nK m  
public class TestMethod { *cy!PF&  
G0lg5iA<fC  
r E&}B5PN=  
public TestMethod() 2o<aEn&7|e  
{ ///xx/weblogic60b2_win.exe W}P9I&3  
try{ DR(/|?k+  
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Oq[YbQ'GE  
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); giH WC%/  
SiteFileFetch fileFetch = new SiteFileFetch(bean); zrL+:/t  
fileFetch.start(); q^ eLbivVE  
} nC5]IYL|  
catch(Exception e){e.printStackTrace ();} VLcwBdo  
,DD}o  
ho%G  
} h'"~t#r  
hH~GH'dnaE  
2v`Q;%7O  
public static void main(String[] args)  s-Qq#T  
{ kL e{3>}j  
new TestMethod(); 6^sH3=#  
} xs^wRE_  
} <"@5. f1"Y  
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
如果您提交过一次失败了,可以用”恢复数据”来恢复帖子内容
认证码:
验证问题:
10+5=?,请输入中文答案:十五