http断点续传简单实现（java)

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0 发表于: 2006-05-10

/*
**SiteFileFetch.java
*/
package NetFox;
import java.io.*;
import java.net.*;

public class SiteFileFetch extends Thread {

SiteInfoBean siteInfoBean = null; //文件信息Bean
long[] nStartPos; //开始位置
long[] nEndPos; //结束位置
FileSplitterFetch[] fileSplitterFetch; //子线程对象
long nFileLength; //文件长度
boolean bFirst = true; //是否第一次取文件
boolean bStop = false; //停止标志
File tmpFile; //文件下载的临时信息
DataOutputStream output; //输出到文件的输出流

//负责整个文件的抓取，控制内部线程（FileSplitterFetch类）
public SiteFileFetch(SiteInfoBean bean) throws IOException
{
siteInfoBean = bean;
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath()));
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info");
if(tmpFile.exists ())
{
bFirst = false;
read_nPos();
}
else
{
nStartPos = new long[bean.getNSplitter()];
nEndPos = new long[bean.getNSplitter()];
}

}

public void run()
{
//获得文件长度
//分割文件
//实例FileSplitterFetch
//启动FileSplitterFetch线程
//等待子线程返回
try{
if(bFirst)
{
nFileLength = getFileSize();
if(nFileLength == -1)
{
System.err.println("File Length is not known!");
}
else if(nFileLength == -2)
{
System.err.println("File is not access!");
}
else
{
for(int i=0;i<nStartPos.length;i++)
{
nStartPos = (long)(i*(nFileLength/nStartPos.length)); &f;<[_QI=
} N084k}io
for(int i=0;i<nEndPos.length-1;i++) (>LJv |wn
{ PQ#zF&gL9t
nEndPos = nStartPos[i+1]; vmY 88Kx&S
} 4P>4d +
nEndPos[nEndPos.length-1] = nFileLength; w[/_o,R
} &4dh$w]q
} ?k}"g$JFn
g5\EVcHkz
;PA^.RB
//启动子线程 4GL-3e
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; |})7\o
for(int i=0;i<nStartPos.length;i++) Rg3cqe#O/
{ G2,9$8qE
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Yu`KHvur
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), (L2:|1P)
nStartPos,nEndPos,i); |)4aIa
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ]bui"-tlK
fileSplitterFetch.start(); 1p|h\H
} #C`IfP./
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 8M_p'AR\,y
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ]E:P-xTwaI
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", Wpdn^=dhL
nEndPos = " + nFileLength); *oW^P~m/
// fileSplitterFetch[nPos.length-1].start(); fl4z'8P"(
X`+8rO[
F4#^jat{
//等待子线程结束 $lC*q
//int count = 0; in[yrqFb7t
//是否结束while循环 MIn6p
boolean breakWhile = false; &l<~Xd#
Z2t r?]
KJLC2,
while(!bStop) k/`WfSM\.
{ ITmW/Im5
write_nPos(); Vlka+$4!
Utility.sleep(500); %z_L}L
breakWhile = true; $.g)%#h:
,Qw\w,
?%]?#4bkc
for(int i=0;i<nStartPos.length;i++) W3h{5\d!
{ `;R [*7
if(!fileSplitterFetch.bDownOver) WNa#X]*E)
{ /BaXWrd+
breakWhile = false; Wb7z&vj
break; :8CYTEc
} M6MtE_E
} q]}1/JZS
if(breakWhile) 1f/8XxTB
break; 6tDCaB
#R#o/@|
L>PPAI
//count++; 'y<<ce*
//if(count>4) by{ *R
// siteStop(); Rc.8j,]
} uTq)Ets3
*9?T?S|^$F
)tB1jcI;
System.err.println("文件下载结束！"); :{tj5P!S
} <M,A:u\qSQ
catch(Exception e){e.printStackTrace ();} V!3.MQM
} WER\04%D\m
LqOjVQxz
~p'DPg4
//获得文件长度 Hrdz1:#6,
public long getFileSize() -g6C;<Y
{ 6lKM5,Oa
int nFileLength = -1; J@4,@+X
try{ CNRiK;nQ
URL url = new URL(siteInfoBean.getSSiteURL()); Ts~)0
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); ,2y" \_
httpConnection.setRequestProperty("User-Agent","NetFox"); 9tZ+?O5
Hc"FW5R
4[$D3,A
int responseCode=httpConnection.getResponseCode(); qt !T%K
if(responseCode>=400) K7 N)VG
{ G"'[dL)N>
processErrorCode(responseCode); ^1 P@BRh
return -2; //-2 represent access is error 1X45~
} B<A=U r
(wtw1E5X
|n_es)A
String sHeader; ktMUTL(B
V.8pxD5s
@N'0:0Nb_
for(int i=1;;i++) sIZ|N"2]A*
{ i H^Gv*
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); dAZh# i[
//Utility.log(in.readLine()); )U':NV2
sHeader=httpConnection.getHeaderFieldKey(i); RlH~<|XK
if(sHeader!=null) mI[$c"!BD
{ Oy `2ccQ#
if(sHeader.equals("Content-Length")) yN Bb(!u
{ UFED*al#
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); M\f1]L|8d
break; tHj |_t
} 5%5z@Ka
} :le"FFfk
else PilV5Gg
break; Q.N, Q`P
} ^z^ UFW
} r,`59
catch(IOException e){e.printStackTrace ();} s=uWBh3J
catch(Exception e){e.printStackTrace ();} I'NE>!=Q
8O)!{gB
)/:&i<Q:
Utility.log(nFileLength); M]Y72K^
#n[1%8l,
#{t?[JUn
return nFileLength; :cmQ w
} (M5{y`Kk
g7|$JevR0
?B&@
//保存下载信息（文件指针位置） ly{Q>MBM
private void write_nPos() 8-wW?YTG
{ LQnkpy3A
try{ '|\et aD
output = new DataOutputStream(new FileOutputStream(tmpFile)); X2MQa:yksP
output.writeInt(nStartPos.length); ;bZIj`D(
for(int i=0;i<nStartPos.length;i++) f.o,VVYi
{ n tfwR#j
// output.writeLong(nPos); .o2]ndT/J
output.writeLong(fileSplitterFetch.nStartPos); 8%$Vj
output.writeLong(fileSplitterFetch.nEndPos); 4RH'GnLa
} &tULSp@J
output.close(); 4<['%7U_[
} sh6F-g
catch(IOException e){e.printStackTrace ();} fDn|o"
catch(Exception e){e.printStackTrace ();} ^Fl6-|^~
} e%v<nGN.-
6!,Am^uXM
K$H>/*&'~
//读取保存的下载信息（文件指针位置） `J>76WN
private void read_nPos() "rjqDpH
{ :\*<EIk(
try{ +G!N@O
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); ERW>G{+
int nCount = input.readInt(); PC| U]
nStartPos = new long[nCount]; J{gqm
nEndPos = new long[nCount]; U#O6l-xe]
for(int i=0;i<nStartPos.length;i++) _u`NIpXSP
{ ?/_8zpW
nStartPos = input.readLong(); ? [?{X~uq
nEndPos = input.readLong(); H:X=v+W
} .qyk[O
input.close(); -}lcMZY
} 959i2z
catch(IOException e){e.printStackTrace ();} K)Nbl^6x
catch(Exception e){e.printStackTrace ();} FQR{w
} 8+&] q#W3
fb5]eec
fq){?hk~O
private void processErrorCode(int nErrorCode) M-!eL<
{ A2o;YyF
System.err.println("Error Code : " + nErrorCode); }}3*tn<6
} Ojkbv
rSIb1zJ
lD!o4ZAo
//停止文件下载 ~RVx~hh
public void siteStop() n%w36_
{ /3*75
bStop = true; *f~X wy"
for(int i=0;i<nStartPos.length;i++) 0gBD
fileSplitterFetch.splitterStop(); %d+:0.+`n
EO'[AU%~
D?rQQxb
} p6(n\egR
} 4-`C !q
//负责部分文件的抓取 (9h{7<wD`
**FileSplitterFetch.java B.&ly/d
*/ W'\{8&:!
package NetFox; I"E5XVC);
E[J7FgU)<S
vrsO]ctI
import java.io.*; ^5biD9>M
import java.net.*; >2gemTy
NYD#I{h
dL<okw
public class FileSplitterFetch extends Thread { Cw]Q)rX{
fmH$1C<
"sz)~Q'W5
String sURL; //File URL 5gg_c?Vh/
long nStartPos; //File Snippet Start Position :8U=L'4
long nEndPos; //File Snippet End Position __""!Yz
int nThreadID; //Thread's ID *k'oP~:fT
boolean bDownOver = false; //Downing is over ~130"WQ;
boolean bStop = false; //Stop identical U]dz_%CRP
FileAccessI fileAccessI = null; //File Access interface A'qJke=
De[!^/f;T
h2+vl@X
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException OWCd$c_(
{ mFOuE5
this.sURL = sURL; >Vc_.dR)E
this.nStartPos = nStart; !z X`M1J
this.nEndPos = nEnd; o[^%0uVF
nThreadID = id; .x$+7$G
fileAccessI = new FileAccessI(sName,nStartPos);//定位 -MoI{3a
} Ul OoMGg
?<,9X06dP
[V()7
public void run() v')Fq[H
{ |UM':Ec
while(nStartPos < nEndPos && !bStop) L #p-AK
{ i NzoDmE*
#"%oz^~\
#b []-L!
try{ 1=OXi!G
URL url = new URL(sURL); ~my\{q
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); uXW<8( %W
httpConnection.setRequestProperty("User-Agent","NetFox"); sN 1x|pkN
String sProperty = "bytes="+nStartPos+"-"; $I~=t{;"XV
httpConnection.setRequestProperty("RANGE",sProperty); S1wt>}w0$
Utility.log(sProperty); 2pH2s\r<UJ
25*/]iu
-ZH]i}$
InputStream input = httpConnection.getInputStream(); XCoN!~
//logResponseHead(httpConnection); e2UbeP
,\4@Ao
c, \TL ]
byte[] b = new byte[1024]; O[3J Px
int nRead; <^|8\<J
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) .l"_f
{ 2X;,s`)
nStartPos += fileAccessI.write(b,0,nRead); {_|~G|Z
//if(nThreadID == 1) ' ~lC85
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); I<z /Y?
} .RH}/D
o;M"C[
d%VGfSrKq
Utility.log("Thread " + nThreadID + " is over!"); {l.) *#O
bDownOver = true; 'CjcOI s
//nPos = fileAccessI.write (b,0,nRead); ny'~pT'00
} "d/x`Dx
catch(Exception e){e.printStackTrace ();} 0wB ?U~
} l~AmHw e
} -lRXH7|X
cgc|G
$TtCVR
//打印回应的头信息 ;n00kel$
public void logResponseHead(HttpURLConnection con) v)!Rir5
{ ?Q="w5OOD
for(int i=1;;i++) 5@P2Z]Q
{ c_x6FoE;L
String header=con.getHeaderFieldKey(i); k]lM%
if(header!=null) v0jRoE#
//responseHeaders.put(header,httpConnection.getHeaderField(header)); [ahD%UxO5
Utility.log(header+" : "+con.getHeaderField(header)); *I(>[m!
else 2TmQaDu%b
break; jl{>>TW{x
} )i0\U
} %L:e~*
?lnX."eAdB
H5S>|"`e`e
public void splitterStop() zK(9k0+s
{ YU9xANi6
bStop = true; )/HSt%>
} I{JU<A,&
W=&\d`><k
:-xp'_\L
} Uxn_nh
m!er"0
vK!,vKa.
/* R4 ;^R
**FileAccess.java MM3X! tq
*//文件访问(定位，写) $T8Ni!#/C
package NetFox; p )etl5
import java.io.*; ~=aGv%vX
eA$9)K1GO
Mou>|U1e"
public class FileAccessI implements Serializable{ Xnt`7L<L
,oT?-PC$z
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 q*{i/=~
RandomAccessFile oSavedFile; QY8I_VF
long nPos; 67+ K ?!,
'M=(5p
m4<8v
public FileAccessI() throws IOException xop9*Z$
{ ^SpD)O{
this("",0); MlkTrKdGi
} T?N' k=
sycN
R;.zS^LL
public FileAccessI(String sName,long nPos) throws IOException S7P](F=n#
{ QKL5! L9`
oSavedFile = new RandomAccessFile(sName,"rw"); ;26a8g(
this.nPos = nPos; -MbnYs)
oSavedFile.seek(nPos); UO5^4
} E}-Y@( [
36`aG Y
&[`p qX
public synchronized int write(byte[] b,int nStart,int nLen) eh2w7@7Q
{ \m1r(*Ar
int n = -1; k|F<?:C
try{ .t.H(Q9
oSavedFile.write(b,nStart,nLen); /k|y\'<
n = nLen; , ?WTX
} - U!:.
catch(IOException e) (Gf1#,/3~
{ ?w`uv9NUJ8
e.printStackTrace (); 1/c7((]7(,
} '*MNRduE6
U 3aY =8B
Qv(}*iq]
return n; }_u1'
} ?k<i e2
P6&@fwJ<
u7ZSs-LuHw
} F&<si:}KB
{1li3K&0s
6]^ShOX_Z
/* A1Ia9@=Mf
**SiteInfoBean.java L,*2tJcC<
*/ lZ.x@hDS
package NetFox; kzny4v[y
v: cO+dQ
fdc ?`4
public class SiteInfoBean { AWsO?|YT
jq yqOhb4
!(~eeE}|lM
private String sSiteURL; //Site's URL V0q./NuO
private String sFilePath; //Saved File's Path %W~Kx_
private String sFileName; //Saved File's Name <e-9We."
private int nSplitter; //Count of Splited Downloading File kA1]o
,+-l1GpL
tsVQXvo
public SiteInfoBean() c"Kl@[1\~
{//nSplitter的缺省值为5 Ox7v*[x'
//default value of nSplitter is 5 |s`j=<rNQI
this("","","",5); )XV|D
} |Wd]:ijJ
) (unL`y
secD `]
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) Pz7{dQqjk#
{ 2a8ZU{wjn
sSiteURL= sURL; wi^zXcVj
sFilePath = sPath; k FE2Vv4.
sFileName = sName; ,~u5SR
this.nSplitter = nSpiltter; h}r*
,r~pf(nz
E/2kX3}
} ^ cpQ*Fz
^ZV1Ev8T6
G8dC5+h
public String getSSiteURL() Zz}Wg@&
{ J}U);A
return sSiteURL; piKYO+;W'
} dZcRLLR
&?UIe]
z+,l"#Vv
public void setSSiteURL(String value) .RFijr
{ s\2t|d
sSiteURL = value; {U@&hE -
} JAJo^}}{b
!iUFD*~r~
|s[kY
public String getSFilePath() tS#=I.ET
{ :EJ8^'0Q
return sFilePath; x}v]JEIf[Q
} Jm8{@D%
[&12`!;j
~,[-pZ<
public void setSFilePath(String value) [Q+8Ku
{ 2..b/
sFilePath = value; u~SvR~OE
} )y>o;^5'
Ilt!O^
7Nx5n<
public String getSFileName() 4@ EY+p
{ E57:ap)/
return sFileName; D>Ij
} tg =ClZ-
v:/+OzY
<ua`WRQr
public void setSFileName(String value) @ 3n;>oi
{ [R V_{F:'
sFileName = value; -Pds7}F8
} ZqT8G
=AEl:SY+
'dJ#NT25
public int getNSplitter() ^na8d's:
{ bu[PQsT
return nSplitter; Fu0"Asxce
} yTt,/+I%gJ
Y2lBQp8'|
XS:W{tL!
public void setNSplitter(int nCount) R(YhVW_l
{ H}v.0R
nSplitter = nCount; R`M>w MLH
} DJ&ni`
} vbFi#|EU
5:S=gARz
OYnxEdo7
/* $H\[yg>4
**Utility.java z"7I5N
*/ _FpZc?=
package NetFox; )y~FeKh
{tS^Q*F
~H<oqk:O-
public class Utility { j:|um&`)
(L`7-6e(Ab
C:r@)Mhq
public Utility() ,<Ag&*YE4
{ `.oWmBey\
_xKuEU}
\\ZR~f!<
} IBP3
Go^a~Sf$
//线程睡眠 e6G=Bq$
public static void sleep(int nSecond) rC!!X
{ ShP&ss
try{ qu8!fFQjYL
Thread.sleep(nSecond); t(~V:+W9
} Bqcih$`BVU
catch(Exception e) ;`")3~M3*
{ p :v'"A}
e.printStackTrace (); 3VI[*b
} 9\dpJ\
} i}tBB~]
Xu.Wdl/{Ra
//日志 _DDknQP
public static void log(String sMsg) Q>ZxJ!B<k
{ D,3Kx ^
System.err.println(sMsg); f6of8BOg
} biLNR"/E
wo#,c(
o[ Je
public static void log(int sMsg) lRk)
{ R^p'gQc$
System.err.println(sMsg); Ri
} |>Ld'\i8
} iH`Q4
~M c'~:{O
/VmtQ{KTt+
/* u# TNW.
**TestMethod.java Sux/='
*/ ia9=&Hy])
package NetFox; yv;KKQ
jW8,}Xs
DXa!"ZU
public class TestMethod { M1mx{<]A
a23XrX
XfYbWR
public TestMethod() sk%Xf,
{ ///xx/weblogic60b2_win.exe hEh` cBO
try{ [yhK4A
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); o*t4zF&n
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); d:vuRK4+
SiteFileFetch fileFetch = new SiteFileFetch(bean); QM) ob
fileFetch.start(); Pf:;iXH?
} n1Wo<$#
catch(Exception e){e.printStackTrace ();} 'PqKb%B|
A"}Ib'
FKH_o
} KSYHG
_2a)b(<tF
B'v~0Kau
public static void main(String[] args) dFl8'D
{ -`A+Qp)
new TestMethod(); m S4N%Q
} jX;$g>P
} "(YfvO+
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