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)); UN`O*(k[
} rs:a^W5t
for(int i=0;i<nEndPos.length-1;i++) =7<g;u
{ AJ85[~(lX
nEndPos = nStartPos[i+1]; -l q,~`v
} {us"=JJVN
nEndPos[nEndPos.length-1] = nFileLength; Lz}mz-N
} N uq/y=
} CYN|
~ ^)4*@i6
l\~F0Z/O
//启动子线程 EB[B0e7}
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; :<`po4/
for(int i=0;i<nStartPos.length;i++) O `a4 ")R
{ 5U%a$.yr
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), TllIs&MCe
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), O\)rp!i
nStartPos,nEndPos,i); UWq[K&vQZ
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); T&kr IZw
fileSplitterFetch.start(); R]Pv=fn
} VeWvSIP,EQ
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), G^_fbrZjN
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); r WPoR/M
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", x<[W9Z'~?9
nEndPos = " + nFileLength); Y%)@)$sK
// fileSplitterFetch[nPos.length-1].start(); Y` tB5P
x8E!Ko](
BFMINq>
//等待子线程结束 _9b;8%?Yf
//int count = 0; OqA#4h4^
//是否结束while循环 OG}m+K&<
boolean breakWhile = false; p*"H&xA@
tD\%SiTg=b
RJT=K{2x
while(!bStop) |fg{Fpc
{ Tjza3M
write_nPos(); 8yn}|Y9Fu
Utility.sleep(500); ^jZ4tH3K
breakWhile = true; g:CMIe4
RS[>7-9
m8<l2O=m
for(int i=0;i<nStartPos.length;i++) /l$>W<}@
{ K na
if(!fileSplitterFetch.bDownOver) JO"-"&>
{ tu0agSpU
breakWhile = false; e-e*%
break; ,xsFBNCC
} e`Vb.E)
} ![4<6/2gy
if(breakWhile) ) v^;"q"
break; qx<h rC0Z&
\-~TW4dYe
Uk|(VR9
//count++; nRlvW{p;
//if(count>4) r__Y{&IO
// siteStop(); =dTsGNz
} b(|1DE0Cv
mu}T,+9\
t^-yK;`?q:
System.err.println("文件下载结束！"); \w\{x0u
} a}MSA/K(
catch(Exception e){e.printStackTrace ();} ^+zhzfJ
} 6+Wkcrh
XhEd9>#
;;g'C*_
//获得文件长度 DKxzk~sOM
public long getFileSize() XKt">W
{ ts3BmfR?
int nFileLength = -1; Km9Y_`?
try{ 3G)Wmmh"a
URL url = new URL(siteInfoBean.getSSiteURL()); XF 8$D
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Y>i?nC%*
httpConnection.setRequestProperty("User-Agent","NetFox"); 0755;26Bx
KM;'MlO
7BDRA},o
int responseCode=httpConnection.getResponseCode(); 7Ta",S@m
if(responseCode>=400) 8rx"D`{|
{ 3>t^Xu~
processErrorCode(responseCode); ME%W,B.|"s
return -2; //-2 represent access is error ;.4A,7w#
} (( D*kd"
o:irwfArv
,3tcti~sZ
String sHeader; pk0Cx
HKZD*E((
7$&3(#!N
for(int i=1;;i++) N?mTAF'M
{ o<r|YRzQl
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); kxp, ZP
//Utility.log(in.readLine()); YYc.e T<
sHeader=httpConnection.getHeaderFieldKey(i); b;XUv4~V
if(sHeader!=null) nR1QS_@{L
{ Dtw1q-
if(sHeader.equals("Content-Length")) -$js5Gx1
{ 0+P<1ui
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); 9OnH3
break; Q(\U'|%J
} !$i*u-%4
} <p74U( V
else !K~:crUV|S
break; xF4>G0
} lSzLR~=Au
} uYv"5U]MFv
catch(IOException e){e.printStackTrace ();} ?-`G0(
catch(Exception e){e.printStackTrace ();} toCxY+"nbU
sw'?&:<"Ow
Gcseq
Utility.log(nFileLength); udV.$N
c{dge/2yb
|*+f N8
return nFileLength; 2HemPth
} ,@1.&!F4it
X<<hb
W+C@(}pt
//保存下载信息（文件指针位置） "V;5Lp b
private void write_nPos() SCZ6:P"$qX
{ ~K-c-Zs#z
try{ 8> -3G
output = new DataOutputStream(new FileOutputStream(tmpFile)); o"a~
output.writeInt(nStartPos.length); ?zD?-
for(int i=0;i<nStartPos.length;i++) {T0f]]}Q
{ ?!:$Z4G
// output.writeLong(nPos); '9Hah
output.writeLong(fileSplitterFetch.nStartPos); D~i m1h;>
output.writeLong(fileSplitterFetch.nEndPos); {{WA=\N8C
} EGZF@#N
output.close(); 5D32d1A
} K5fL{2V?
catch(IOException e){e.printStackTrace ();} A@kp`-
catch(Exception e){e.printStackTrace ();} u::2c
} "XEKoeG{
'F- wC!
lbCTc,xT
//读取保存的下载信息（文件指针位置） Vg0$5@
private void read_nPos() q@}eYQ=P|e
{ !e}LB%zf
try{ JToc("V
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); #=G[~m\
int nCount = input.readInt(); x!A.**
nStartPos = new long[nCount]; b`=\<u8
nEndPos = new long[nCount]; %ifq4'?Z
for(int i=0;i<nStartPos.length;i++) '<A:`V9M}v
{ I}#_Jt3R
nStartPos = input.readLong(); /NH9$u.g
nEndPos = input.readLong(); $&@L[[xl
} 19u'{/Y"
input.close(); LvsNU0x
} =X0"!y"
catch(IOException e){e.printStackTrace ();} /~49.}yt
catch(Exception e){e.printStackTrace ();} q^e4
} 9D2}heTN
CO`%eL~
V?a+u7*U&
private void processErrorCode(int nErrorCode) |-W7n'n
{ OKo39 A\fu
System.err.println("Error Code : " + nErrorCode); G/2| *H
} \Qh{uk[
x>?jfN,e
>>**n9\q
//停止文件下载 ndIf1}
public void siteStop() 39|4)1e
{ bvf}r ,`Q7
bStop = true; )jh4HMvmC
for(int i=0;i<nStartPos.length;i++) D]H@Sx
fileSplitterFetch.splitterStop(); U9d0nj9 j
W3XVr&
[/s^(2%
} CMm:Vea
} kIb)I(n
//负责部分文件的抓取 NDJIaX:]
**FileSplitterFetch.java iBq|]
*/ pohA??t2:
package NetFox; SD"'
Ye'=F
x*G-?Xza)
import java.io.*; dPdodjSu,!
import java.net.*; GWNLET
l Ikh4T6i
{xw"t9(fE
public class FileSplitterFetch extends Thread { 1^*M*>&d<
z%Xz*uu(|
zHI_U\"8D
String sURL; //File URL wF +9Iu
long nStartPos; //File Snippet Start Position tFY;q##z
long nEndPos; //File Snippet End Position >IL[eiiPG
int nThreadID; //Thread's ID vPm&0,R*y:
boolean bDownOver = false; //Downing is over c~@Z
boolean bStop = false; //Stop identical -'j_JJ
FileAccessI fileAccessI = null; //File Access interface q K sI}X~
7IrbwAGZ3
y#4f^J!V
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException a@E+/9
{ qno8qF*
this.sURL = sURL; #}/YnVk
this.nStartPos = nStart; 3fS+,>s\O
this.nEndPos = nEnd; 4,8=0[eRG
nThreadID = id; N3D{t\hg
fileAccessI = new FileAccessI(sName,nStartPos);//定位 )jM' x&Vg
} =l %
e/pZLj]M
tevB2'3^
public void run() PdUlwT?8C
{ :x36^{7
while(nStartPos < nEndPos && !bStop) OJ (ho&((
{ Ow0-}Im~
p;[">["
xWwQm'I2}
try{ 7oj ^(R,
URL url = new URL(sURL); G:W4<w
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); u&q RK>wLa
httpConnection.setRequestProperty("User-Agent","NetFox"); P}] xz Vy
String sProperty = "bytes="+nStartPos+"-"; HN/ %(y
httpConnection.setRequestProperty("RANGE",sProperty); v"y0D
Utility.log(sProperty); .AIlv^:|U
5pF4{Jd1
ze+_iQ5
InputStream input = httpConnection.getInputStream(); 6qW/Td|g
//logResponseHead(httpConnection); Md~% e'
0y>]68D
YVzcV`4w(
byte[] b = new byte[1024]; }ze,6T*z
int nRead; cQ= "3M)~r
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) RTPxAp+\5
{ ::k>V\;
nStartPos += fileAccessI.write(b,0,nRead); FtaO@5pS54
//if(nThreadID == 1) k<1BE^[V
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); c-|~ABtEpX
} "pP5;*^f
V-#OiMWa~
_|VWf8?\
Utility.log("Thread " + nThreadID + " is over!"); dKs^Dq
bDownOver = true; J^}w,r*=
//nPos = fileAccessI.write (b,0,nRead); o5!"dxR
} Q_ zGs6
catch(Exception e){e.printStackTrace ();} Rgb1B3gu
} {`2R<O
} .T*K4m{b0
X6+2~'*t
I%.96V
//打印回应的头信息 ~hubh!d=
public void logResponseHead(HttpURLConnection con) OQ[E-%v1 R
{ fs8nYgv|Q
for(int i=1;;i++) KC+C?]~M
{ h5+qP"n!?q
String header=con.getHeaderFieldKey(i); K"p$ga{
if(header!=null) >Oary
//responseHeaders.put(header,httpConnection.getHeaderField(header)); c,ccavv{I
Utility.log(header+" : "+con.getHeaderField(header)); t`PA85.|d
else ']nB_x7
break; [@SLt$9"
} 4dkU;Ob
} AJ0qq
]_cBd)3P}
YeN /J.R
public void splitterStop() ttEQgkd`
{ Y^zL}@
bStop = true; Gk'j<a
} <SiD m-=E
7@[3]c<=
bjgf8427I
} %9|}H [x
p&B c<+3e
jft%\sY
/* e-$U .cx
**FileAccess.java %+PWcCmn
*//文件访问(定位，写) J. ]~J|K
package NetFox; 3j{VpacZY
import java.io.*; d3A= (/>D
O>zPWVwa
y[U/5! `zV
public class FileAccessI implements Serializable{ 8.Q;o+NU
E0K'|*
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 "AN2K
RandomAccessFile oSavedFile; em^|E73
long nPos; l,FK\
dXAKk[uf
Kjbz\~
public FileAccessI() throws IOException y`"~zq0D
{ //c<p
this("",0); :D-xa!7
} T*,kBJ
*/=5m]
"NUl7ce.R
public FileAccessI(String sName,long nPos) throws IOException f/spJ<B).4
{ [Z2:3*5r.
oSavedFile = new RandomAccessFile(sName,"rw"); /*5t@_0fe
this.nPos = nPos; t;P%&:"@M
oSavedFile.seek(nPos); +r7uIwi$@
} ]~my<3j}or
gu+c7qe
=NyN.^bwT
public synchronized int write(byte[] b,int nStart,int nLen) mQRQ2SN6
{ C-@
int n = -1; -4P2 2
try{ Evd>s
oSavedFile.write(b,nStart,nLen); L2s)B
n = nLen; }}a<!L,{
} @\[UZVmBw
catch(IOException e) "%O,*t
{ _Je k;N
e.printStackTrace (); #qk}e4u
} .@0i,7S
DKV^c'
$gi{)'z
return n; v#iKa+tx
} >|<8QomD
9>qc1z
*/gm! :Ym
} "0pH@_8o{
>n,RBl
#(o 'G4T
/* 5oz[Njq4
**SiteInfoBean.java (bfHxkR.
*/ D#>+]}5@x
package NetFox; pdnkHR$
Xg*IOhF6x
lk $S"OH!
public class SiteInfoBean { 3c5=>'^F
xyO]Evg
ygm4Aj>
private String sSiteURL; //Site's URL k0|*8
private String sFilePath; //Saved File's Path h:QKd!Gq
private String sFileName; //Saved File's Name *uYnu|UQH
private int nSplitter; //Count of Splited Downloading File '</
Jhbkp?Zli
OtuOT=%
public SiteInfoBean() H-%)r&"vn
{//nSplitter的缺省值为5 MF>1u%
//default value of nSplitter is 5 ?>lvV+3^`
this("","","",5); u@SE)qg
} ajy.K'B*
Q1qf'u
8Rq+eOP=S
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ZoJ:4uo N`
{ fo])=KM
sSiteURL= sURL; g`KVF"8
sFilePath = sPath; {;4AdZk
sFileName = sName; ^FSUK
this.nSplitter = nSpiltter; 9wLV\>i[k
~__]E53F
y6KI.LWR9
} tN|sHgs
y}jX/Ln
Va"_.8n|+
public String getSSiteURL() M 7j0&>NTG
{ zuOx@T^
return sSiteURL; ?'H);ou-p
} /kGRN@
^n5[pF}Gw
M70Xdn
public void setSSiteURL(String value) ;$W/le"Xr
{ +O23@G?x
sSiteURL = value; '>(R'g42n
} Mf0g)X}1
T:Dp+m!\{
]saf<?fzr
public String getSFilePath() se](hu~w
{ ;czMsHu0X
return sFilePath; iqCKVo7:M
} hx$-d}W{
o"@y=n/
2BOe,giy
public void setSFilePath(String value) }zVPdBRfm
{ S5ka;g
sFilePath = value; a pqzf
} rkA0v-N6v
0;'kv|
Y>-|`2Z
public String getSFileName() 4%O*2JAw
{ c_xtwdkL9
return sFileName; [X:mmM0gd
} za7h.yK}
pYV$sDlD
j(G}4dib
public void setSFileName(String value) 1E!0N`E
{ *W q{ :k
sFileName = value; o[*</A }
} }*l V
ann!"s_
e!yUA!x`u
public int getNSplitter() vrXmzq
{ kNfqdCF{P
return nSplitter; W5?F?Dp!v
} HGmgQ>q@M$
'X{cDdS^
ws5x53K
public void setNSplitter(int nCount) &NV[)6!
{ (5?5? <
nSplitter = nCount; Okca6=2"
} 0B)l"$W[)/
} #"d.D7nA
d -6[\S#
w3:WvA5jt
/* DHGv< F@
**Utility.java { 'Hi_b3
*/ 4*OL^\%
package NetFox; vOsd>3"
cs`/^2Vf"#
Y."ujo#bB
public class Utility { %a+X\\v2
R3F>"(P@tS
!c:Q+:,H
public Utility() \Q{@AC<?i
{ &V1N a1`
S{j|("W"[
H V<|eL #
} a>`\^>G4
[8.ufpZ
//线程睡眠 "|`8mNC
public static void sleep(int nSecond) K|];fd U
{ +Tc4+q!
try{ "5e~19
Thread.sleep(nSecond); =<(:5ive
} *=dFTd"#
catch(Exception e) 1Nw&Z0MI
{ ?UQVmE&
e.printStackTrace (); ^4]#Ri=U
} *x[B g]/
} N+l~r]: &
([UuO}m-
//日志 AL! ^1hCF
public static void log(String sMsg) c&)H
{ Jl&bWp^3
System.err.println(sMsg); j11\t
} ,Ihuo5>/z
( gO?-0
>yUThhJRn
public static void log(int sMsg) KgVit+4u/
{ "e g`3v
System.err.println(sMsg); %@$h?HP
} q#v.-013r
} QRdNi1&M
'T7JXV5
RGhl`;
/* o^4qY
**TestMethod.java #h ;j2
*/ WM: ~P$%cx
package NetFox; 28SlFu?
rui}a=rs
[e3|yE6
public class TestMethod { 9:A>a3KOH
'*!R gbj;
*jGB/ y
public TestMethod() [6 wI22
{ ///xx/weblogic60b2_win.exe [V{JuG;s
try{ KoiU\r
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); 64s+ 0}
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); B P"PUl:
SiteFileFetch fileFetch = new SiteFileFetch(bean); ^j';4'
fileFetch.start(); l7aGo1TcIh
} Xn"n5=M
catch(Exception e){e.printStackTrace ();} m0]LY-t
*x`z5_yfO
FFbMG:>:
} <.$<d
dJ?VN!B0
R%aH{UhE`
public static void main(String[] args) b@^M|h.Va
{ lZ0+:DaP2
new TestMethod(); T;GBZR%
} V-A^9AAPm
} a%tm[Re
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