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)); _ev^5`>p/
} ) AIZE?oX
for(int i=0;i<nEndPos.length-1;i++) F=H=[pSe
{ rX[R`,`>Z[
nEndPos = nStartPos[i+1]; K!X8KPo
} ZmDr$iU~
nEndPos[nEndPos.length-1] = nFileLength; f$L5=V
} wP i=+
} FoLwS%+yO
i F Ab"VA
:?TV6M
//启动子线程 @`yfft
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; d=pq+
for(int i=0;i<nStartPos.length;i++) ]iPdAwc.1
{ Y!H"LI
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), S@_GjCpn
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Q. >"@c[
nStartPos,nEndPos,i); 8c#*T%Vf
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); uf6{M_jXZ
fileSplitterFetch.start(); TBpW/wz/
} p0/I}n4<5n
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), VybiuP
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); A-<qr6q
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", sbVeB%k
nEndPos = " + nFileLength); D 6(w}W
// fileSplitterFetch[nPos.length-1].start(); C5m*pGImG
1+]e?
~ rRIWfhb
//等待子线程结束 'ySWf,Q^
//int count = 0; gaJS6*P#
//是否结束while循环 r8qee$^M
boolean breakWhile = false; |Q{l]D
Uc&0>_Z
wL*z+>5
while(!bStop) UuN(+&oD-
{ OS3J,f}<=
write_nPos(); =I?p(MqW
Utility.sleep(500); d;>:<{z@CD
breakWhile = true; q+N}AKawB
:Qf^@TS}O
9:P)@UF
for(int i=0;i<nStartPos.length;i++) te1lUQ
{ *e^ZH
if(!fileSplitterFetch.bDownOver) E*kS{2NAq
{ $T1c{T6n}
breakWhile = false; pgI@[zp7
break; N@k:kI
} S"lcePN
} U_w)*)F
if(breakWhile) Q (`IiV
break; ]^s4NXf+
k|w6&k3
<Wl! Qog'
//count++; IqmavnM#
//if(count>4) ==$Ox6.
// siteStop(); 1aSuRa
} BV<LIrAS
K\ZKVn
;]p#PNQ0
System.err.println("文件下载结束！"); E;%{hAD{
} py)V7*CgH
catch(Exception e){e.printStackTrace ();} O^LzS&I*
} _wm"v19
M5D,YC3<
p_[k^@$
//获得文件长度 Uq"RyvkpP
public long getFileSize() gp;(M~we
{ z.7 UfLV9
int nFileLength = -1; .sCo,
try{ F> ..eK
URL url = new URL(siteInfoBean.getSSiteURL()); lO<Ujb#"R
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); eqXW|,zUm
httpConnection.setRequestProperty("User-Agent","NetFox"); t@b';Cuv
&bTadd%0
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int responseCode=httpConnection.getResponseCode(); jo+T!CUM'
if(responseCode>=400) #t9&X8:U
{ -Ndd6O[ a5
processErrorCode(responseCode); cJL>,Z<|%
return -2; //-2 represent access is error bD=_44I
} 24]O0K
}&ZO q'B
OfIml.
String sHeader; CI ~+(+q
u2o6EU`
p-MQI }
for(int i=1;;i++) E+csK*A7
{ ) 3Eax_?Z
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); !i0:1{.
//Utility.log(in.readLine()); ,f4Hl%T;
sHeader=httpConnection.getHeaderFieldKey(i); h2K1|PUKl[
if(sHeader!=null) q^k6.5*"
{ ,253'53W)
if(sHeader.equals("Content-Length")) 8q}`4wCD$
{ {'EQ%H$q
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); -g_PJ.Hk
break; HP"5*C5D
} |Kh#\d
} rWAJL9M
else l\8l.xP
break; -CW$p=y}
} Q"]C"?
} ~mUP!f
catch(IOException e){e.printStackTrace ();} u(KeS`
catch(Exception e){e.printStackTrace ();} \IQP`JR
i>bFQ1Rdx
BaIh,iu
Utility.log(nFileLength); ]2Aqqy
Vxif0Bx&/d
DBi3 j
return nFileLength; ;(3fr0cr:
} $UlA_l29
_:om(gL
F'ZLN]"{
//保存下载信息（文件指针位置） di6A.N5A
private void write_nPos() wxPg*R+t
{ d87pQ3e:&
try{ La}=Ng
output = new DataOutputStream(new FileOutputStream(tmpFile)); DSix(bs9
output.writeInt(nStartPos.length); #m9V)1"wB
for(int i=0;i<nStartPos.length;i++) &Qghm o
{ hB<.u
// output.writeLong(nPos); {rOz[E9vm
output.writeLong(fileSplitterFetch.nStartPos); <u44YvLBm
output.writeLong(fileSplitterFetch.nEndPos); d; @Kz^
} hBLg;"=Em
output.close(); kYs2AzS{d
} J.":oD
catch(IOException e){e.printStackTrace ();} HkxFDU-K
catch(Exception e){e.printStackTrace ();} URR|Q!D
} e dD(s5
6s|C:1](b
Y,&)%Eo<
//读取保存的下载信息（文件指针位置） "ht2X w
private void read_nPos() %|,j'V$
{ f'%}{l: ss
try{ TkQ05'Qc
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); *YDx6\><
int nCount = input.readInt(); % mIq,
nStartPos = new long[nCount]; MOOL=Um3
nEndPos = new long[nCount]; =n#xnZ3
for(int i=0;i<nStartPos.length;i++) ke/o11LP
{ HWs?,AJNxB
nStartPos = input.readLong(); q+m&V#FT%
nEndPos = input.readLong(); 4z$eT
} N:&Gv'`
input.close(); ]AfeaU'>
} 12rr:(#%s
catch(IOException e){e.printStackTrace ();} nq$^}L3&~
catch(Exception e){e.printStackTrace ();} U1&m-K
} [(dAv7YbN
02=eE|Y@
s=KA(4p
private void processErrorCode(int nErrorCode) Li7/pUq>}!
{ 4ci @$nL1
System.err.println("Error Code : " + nErrorCode); +i K.+B
} @s@r5uR9B
7, O_'T &
<K2 )v~
//停止文件下载 ?N`W,
public void siteStop() G2em>W_n
{ t4 aa5@r
bStop = true; tF=96u_X
for(int i=0;i<nStartPos.length;i++) :MJTmpq,
fileSplitterFetch.splitterStop(); |~uCLf>
1 "4AS_Q
'5{gWV`
} <.:B .k
} U?.VY@
//负责部分文件的抓取 jgukW7H
**FileSplitterFetch.java `A?/Ww>;
*/ 1vQ*Br
package NetFox; 6LUB3;g7
H!7/U_AH
r1t TY?
import java.io.*; M`S >Q2{
import java.net.*; ?L7z\b"_~
|nv8&L8
S{&;
public class FileSplitterFetch extends Thread { <sn^>5Ds
I)n%aTfo8
2}hEBw68
String sURL; //File URL OBu$T&
long nStartPos; //File Snippet Start Position [9*+s
long nEndPos; //File Snippet End Position $1/yc#w u
int nThreadID; //Thread's ID joYj`K
boolean bDownOver = false; //Downing is over Y+lZT4w
boolean bStop = false; //Stop identical Sh=z
FileAccessI fileAccessI = null; //File Access interface 'V } -0
*<]ulR2
M/>^_zG
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException U%m,:b6V
{ }zj_Pp
this.sURL = sURL; E ekX|*
this.nStartPos = nStart; X`#vH8
this.nEndPos = nEnd; kwWDGA?zFB
nThreadID = id; }-!0d*I
fileAccessI = new FileAccessI(sName,nStartPos);//定位 CKy' 8I9
} 8FU8E2zo
oyK'h9Wt1
c7,p5[
public void run() !w{4FE74
{ o4\\q66K
while(nStartPos < nEndPos && !bStop) 'HzF/RKh
{ iTwb#Q=
? 0p_/mZ
;y/&p d+
try{ J>TNyVaoQ
URL url = new URL(sURL); *3d+ !#;rG
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); mA@FJK_
httpConnection.setRequestProperty("User-Agent","NetFox"); C[6} 8J|
String sProperty = "bytes="+nStartPos+"-"; Z8%?ej`8
httpConnection.setRequestProperty("RANGE",sProperty); #~BsI/m
Utility.log(sProperty); of659~EIW
n 9PYZxy
)[+82~F
InputStream input = httpConnection.getInputStream(); _(l?gj
//logResponseHead(httpConnection); ;G.5.q[A
aS=-9P;v
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byte[] b = new byte[1024]; kOdXbw9v
int nRead; "ngULpb{R
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ,sI<AFI
{ 70Jx[3vr
nStartPos += fileAccessI.write(b,0,nRead); z?dd5.k
//if(nThreadID == 1) cD6S;PSg
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); p>_Qns7W
} _rM?g1}5j
o=J-Ju
Kv0V`}<Yc
Utility.log("Thread " + nThreadID + " is over!"); 5C0![$W>
bDownOver = true; :^7>kJ5?
//nPos = fileAccessI.write (b,0,nRead); Co>e<be%S
} =' uePM")
catch(Exception e){e.printStackTrace ();} 1r$*8|p
} V56WgOBxz
} I+=+ ,iXhB
V6Mt;e)C
A]Bf&+V
//打印回应的头信息 -M/j&<;LW
public void logResponseHead(HttpURLConnection con) vjjVZ
{ n,U?]mr
for(int i=1;;i++) /sfJ:KP0
{ |Dt_lQp#
String header=con.getHeaderFieldKey(i); o?Aj6fNY?
if(header!=null) b9-IrR4h
//responseHeaders.put(header,httpConnection.getHeaderField(header)); ,qx^D
Utility.log(header+" : "+con.getHeaderField(header)); a`L:E'|B9
else SQ_Je+X
break; p^CTHk_|
} fqhL"Ah
} jMgXIK\
-QroT`gy
;I&VpAPx
public void splitterStop() T5 (|{-
{ ;xZjt4M1
bStop = true; oQ 2$z8
} ;eN ^'/4A
6|zhqb|s
&E_a0*)e
} x2rAB5r6
JVYH b 60Z
8NWo)y49H
/* W6&vyOc
**FileAccess.java Qc; kj
*//文件访问(定位，写) %up?70
package NetFox; 4f([EV[6dK
import java.io.*; %GHGd'KO&
"9wD|wsz
zaqX};b
public class FileAccessI implements Serializable{ BmG(+;;&
*'?7OL
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 {FNkPX
RandomAccessFile oSavedFile; *yu}e)(0
long nPos; u^1#9bAW8
K#0TD("
*\sPHz.
public FileAccessI() throws IOException o4);5~1l
{ _)M,p@!?=h
this("",0); CL|/I:%0
} *m~-8_ >;
c0oHE8@
LQ jbEYp
public FileAccessI(String sName,long nPos) throws IOException Smr{+m a
{ fpD$%.y'J
oSavedFile = new RandomAccessFile(sName,"rw"); xN1P#
this.nPos = nPos; hH %>
oSavedFile.seek(nPos); 9R50,lsE
} K^Awf6%
KdkA@>L!;
-V2\s
public synchronized int write(byte[] b,int nStart,int nLen) t`Kbm''d[
{ CXa[%{[n
int n = -1; U2q6^z4l
try{ IH]9%d)
oSavedFile.write(b,nStart,nLen); eS`VI+=@0
n = nLen; +yGQt3U
} '![oLy
catch(IOException e) t" .Ytz>
{ d1b]+AG4
e.printStackTrace (); D|]BFu)F
} _BczR:D*
Lc3&\q e
}qNc`8h
return n; IG781:,/
} |=?#Xbxz
#36QO
A#{63_H
} I6>J.6luF9
'xwCeZcg
k3~9;Z
/* "yWw3(V2>
**SiteInfoBean.java {o=?@$6C
*/ -%nD'qy,.
package NetFox; q7R]!zk
Ve,g9I
TT$Ao
public class SiteInfoBean { -dntV=
e#"h@kZP
Knq9"k
private String sSiteURL; //Site's URL v+c>iI
private String sFilePath; //Saved File's Path x7j#@C
private String sFileName; //Saved File's Name SN{z)q
private int nSplitter; //Count of Splited Downloading File 5>k:PKHL
B9v>="F
U1RU2M]v
public SiteInfoBean() rIyH/=;
{//nSplitter的缺省值为5 ?J}Q&p.
//default value of nSplitter is 5 >lI7]hbIs
this("","","",5); Z8$}Rpo
} Y\|#Lu>B
Zk3Pv0c
20:F$d
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) gI+8J.AG=
{ 12$0-@U
sSiteURL= sURL; 4S_ -9&z
sFilePath = sPath; dcz?5O_{,
sFileName = sName; hI[} -
this.nSplitter = nSpiltter; +v~xgUs
O-iE0t
y^.66BH
} }Zhe%M=}G
UaT%tv>}8#
z;OYPGvkw
public String getSSiteURL() &L o TO+
{ aDlp>p^E>
return sSiteURL; X.]I4O&_
} G0FzXtu)q
xtV+Le%
[4)Oi-_Y>
public void setSSiteURL(String value) b)wcGBS
{ i'tMpS3
sSiteURL = value; K)Y& I
} Vl^(K_`(
1wSAwpz
Sp`l>BL
public String getSFilePath() FU`(mQ*Yd
{ qkKl;Z?Y:
return sFilePath; ^R:&c;&,
} keC'/\e
,=\.L_'
uGz)Vz&3
public void setSFilePath(String value) mt+i0PIfj
{ m"rht:v5
sFilePath = value; XA<h,ONE?
} $ (;:4
"LTw;& y
Eu' ;f_s
public String getSFileName() ,r*Kxy
{ IDn<5#
return sFileName; y>}r
} |` ~ioF
k Nc-@B
7)QZ<fme
public void setSFileName(String value) F oC $X
{ C*ep8{B
sFileName = value; Jy/< {7j
} 1iY4|j;ahV
xI{fd1
\_O#M
public int getNSplitter() .Pj<Pe
{ R/x3+_.f
return nSplitter; Q k}RcP
} uSXnf
EFDmNud`Q
vUbgSI
public void setNSplitter(int nCount) u^SInanw
{ #Db^*
nSplitter = nCount; uzQj+Po
} O\Y*s
} ]/h$6mrL
h(kPf]0
>{Ayzz>v
/* XS2/U<sd
**Utility.java 1:<n(?5JI
*/ =k d-rIBc
package NetFox; =),ZZD#J
q<.k:v&
nt_Cb*K<
public class Utility { ~1TT?H
&jEw(P&_
MjQ>&fUK
public Utility() ?r|iZKa
{ T] H'l
y)|d`qC\
? .B t.
} JO]?u(m01
jXmY8||w
//线程睡眠 1h`F*:nva
public static void sleep(int nSecond) VXk[p
{ PfYeV/M|
try{ CEkf0%YJ
Thread.sleep(nSecond); bhDqRM
} ;xh.95BP`
catch(Exception e) w$s6NBF7
{ o:UNSr
e.printStackTrace (); rvhMu}.
} 9:%')M&Q
} ci?\W6
8rJf2zL
//日志 rUV'DC?eE
public static void log(String sMsg) \v:Z;EbX
{ D)4#AI
System.err.println(sMsg); $5ea[nc
} e GAto
9;*B*S~znW
EN^L.q9#
public static void log(int sMsg) to_dNJbv
{ YJwI@E(l$
System.err.println(sMsg); (O:&RAkk7
} g]MgT-C|
} (G{:O
2GigeN|1N
8rBa}v9
/* UaXIrBc
**TestMethod.java B;iJ$gt]
*/ u&`rK7J
package NetFox; 1'&HmBfcb
hE\gXb
|P9MhfN
public class TestMethod { g("[wqgG
/viBJ`-O
KCa@0
public TestMethod() =`MQKh,
{ ///xx/weblogic60b2_win.exe #="Lr4T
try{ %t.\J:WN;
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); ?6\A$?
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); Wb^g{F!W
SiteFileFetch fileFetch = new SiteFileFetch(bean); PEtr8J$uB
fileFetch.start(); hR[_1vuIu
} L?(1 [jB4G
catch(Exception e){e.printStackTrace ();} RBeQT=B8~
2F,?}jJ.K
riglEA[^
} _(@ezX.p
:?3y)*J!
;ejtP #$
public static void main(String[] args) #@uF?8u
{ 59_VC('
new TestMethod(); f5CnJhE|)
} h4>q~&Pd
} _cc9+o
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