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)); 6}KZp~s
} &|`C)6[C
for(int i=0;i<nEndPos.length-1;i++) m,t|IgDh
{ VV9_`myN7
nEndPos = nStartPos[i+1]; &c*^VL\
} +|ycvHd
nEndPos[nEndPos.length-1] = nFileLength; `3Uj{w/Q:L
} b?j< BvQ
} gc?#pP
4DOK4{4?5
p}<w#p |
//启动子线程 d%0~c'D8a
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; nO)X!dp}J
for(int i=0;i<nStartPos.length;i++) ~D|5u\D-
{ "kA*Vc#
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), gy;+_'.j
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), KW7UUXL
nStartPos,nEndPos,i); T]?n)L,2
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); >|Cw\^
fileSplitterFetch.start(); b%Eei2Gm%
} <2nZ&M4/s{
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ,do58i K
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); IO/4.m-aN#
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", o^V(U~m]
nEndPos = " + nFileLength); /P 2[:[w
// fileSplitterFetch[nPos.length-1].start(); yA3wtm/?
Tdc3_<1
_Um d
//等待子线程结束 ~%2pp~1K
//int count = 0; `w.AQ?p@
//是否结束while循环 r lKlpl
boolean breakWhile = false; Rtjqx6-B;
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nIvJrAm4k
while(!bStop) UG<79"\i
{ g(|6~}|o+
write_nPos(); 8+Td-\IMk
Utility.sleep(500); 0=="^t_
breakWhile = true; -&e92g&n
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tM#lFmdd\P
for(int i=0;i<nStartPos.length;i++) ,Hgc-7g@Y
{ s-ZI ^I2\
if(!fileSplitterFetch.bDownOver) z~\t|Z]G,|
{ !(t,FYeH
breakWhile = false; cGwf!hA
break; &,.Y9; b
} 1+7GUSIb
} {W\T"7H
if(breakWhile) [+Y{%U
break; _qWliw:0#
&''WRgZ}
dr<<!q /
//count++; RJeSi`19T)
//if(count>4) zT ZVehEe
// siteStop(); ;;)`c/$
} UgN28YrW
dz[ bm<T7
wl1m*`$
System.err.println("文件下载结束！"); &Z^l=YH,
} dC1V-x10ju
catch(Exception e){e.printStackTrace ();} =\t /u
} 2Cg$,#H
|*mL1#bB
RB?V7uX
//获得文件长度 _u}4j9T
public long getFileSize() $Q+s/4\
{ _P?\.W@
int nFileLength = -1; 90xk$3(
try{ ai*b:Q
URL url = new URL(siteInfoBean.getSSiteURL()); [ REf>_R
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); eb|i3.
httpConnection.setRequestProperty("User-Agent","NetFox"); nNmsr=y5
u z\0cX_
+!0eu>~_&
int responseCode=httpConnection.getResponseCode(); gf)t)-E
if(responseCode>=400) V#q}Wysft
{ mceG!@t
processErrorCode(responseCode); P;]F=m+*V
return -2; //-2 represent access is error 2-0$FQ@/
} V,ZY*f0
{I{:GcS
rp7W }P+uU
String sHeader; Tx%VU8\?n
->lu#;A5
Zt E##p
for(int i=1;;i++) A 699FQ
{ x6'^4y])
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); T{vR,
//Utility.log(in.readLine()); lnbmoHv
sHeader=httpConnection.getHeaderFieldKey(i); UF__O.l__
if(sHeader!=null) PKq-@F%X
{ h?,\(KjP#
if(sHeader.equals("Content-Length")) uM(UO,X
{ `xKFqx:e
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); %|XE#hw
break; ?HHzQ4w%{
} Me:{{-V4
} p D=w>"
else 2)/NFZ
break; gd^Js1Z
} ,R wfp=*E
} gH:ArfC
catch(IOException e){e.printStackTrace ();} gY9\o#)<
catch(Exception e){e.printStackTrace ();} d @rs3Q1z
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Utility.log(nFileLength); .gYt0raSY
2>hz_o{5',
yqSY9EX7
return nFileLength; ^i_Iqph=
} %(LvE}[RJ
hRTMFgO
ms~8QL
//保存下载信息（文件指针位置） Ttv9"z
private void write_nPos() S]2 {ZDP
{ S_8r\B[>P
try{ 5 d ;|=K
output = new DataOutputStream(new FileOutputStream(tmpFile)); t<b3K-
output.writeInt(nStartPos.length); %AR^+*Nu
for(int i=0;i<nStartPos.length;i++) #s+X+fe
{ Rrqg[F+
// output.writeLong(nPos); m4/}Jx[
output.writeLong(fileSplitterFetch.nStartPos); T{S4|G1R6
output.writeLong(fileSplitterFetch.nEndPos); H+cNX\,
} }e=e",eAT
output.close(); YBSl-G'
} YU\Gj S~>&
catch(IOException e){e.printStackTrace ();} 9qH[o?]
catch(Exception e){e.printStackTrace ();} l_+A5Xy
} <TjBd1
N8+P
`fW{yb
//读取保存的下载信息（文件指针位置） d=e{]MG(
private void read_nPos() u@D.i4U
{ fS./y=j(X
try{ 4r*Pa(;y
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 6An{3"
int nCount = input.readInt(); k|#Zy,
nStartPos = new long[nCount]; aIu2>
nEndPos = new long[nCount]; Vj!WaN_
for(int i=0;i<nStartPos.length;i++) ? ICDIn
{ H7jTQW0rp5
nStartPos = input.readLong(); uL>:tb
nEndPos = input.readLong(); $,P\)</VR
} SOI)/u
input.close(); 4e/cqN6
} Uh\]?G[G
catch(IOException e){e.printStackTrace ();} AM?Ec1S #a
catch(Exception e){e.printStackTrace ();} l"L+e!B~
} 5&qY3@I7l
r|bPR!0
q u:To7
private void processErrorCode(int nErrorCode) Nu+wL>t
{ f+^c@0que
System.err.println("Error Code : " + nErrorCode); Ps7_-cH
} s7|3zqi
wWFW,3b
uWrFunh%
//停止文件下载 uTw|Q{f
public void siteStop() 6JWGu/A
{ @tQ2E}psP,
bStop = true; /Tcb\:`9
for(int i=0;i<nStartPos.length;i++) z'e1"Y.
fileSplitterFetch.splitterStop(); ] ?9t-
%/md"S
qSR?,G
} gDj_KKd
} <>&89E%j'
//负责部分文件的抓取 [>wzl"cHW
**FileSplitterFetch.java %Il;B~t
*/ J5-rp|
package NetFox; 1>yha j(K
}JH`'&3
3f,u}1npa*
import java.io.*; oc=tI@W
import java.net.*; Yd.027
G ;jF9i
oX#9RW/ >I
public class FileSplitterFetch extends Thread { }`4K)(>4nG
BM.-X7)
|9x%gUm
String sURL; //File URL T[m ~6
long nStartPos; //File Snippet Start Position =;g=GcVK
long nEndPos; //File Snippet End Position =s6E/K
int nThreadID; //Thread's ID :(+]b
boolean bDownOver = false; //Downing is over U* 4{"
boolean bStop = false; //Stop identical N]V/83_
FileAccessI fileAccessI = null; //File Access interface yIlV[_
.r(^h/IF
z?I+u*rF6
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException $}V7(wu 6@
{ l~4_s/
this.sURL = sURL; Cv0&prt
this.nStartPos = nStart; 9y;y7i{>?
this.nEndPos = nEnd; ;Sy/N||
nThreadID = id; !W0P`i<
fileAccessI = new FileAccessI(sName,nStartPos);//定位 #`r(zI[
} vT&j{2U7XW
$R8>u#K!
]v<d0"2
public void run() 'n>EEQyp'
{ 2\DTJ`Y,
while(nStartPos < nEndPos && !bStop) o; 6fvn
{ _r~!O$2
ZK%Kgk[\:~
q^)=F_QvG
try{ ]sf2"~v
URL url = new URL(sURL); 4 0p3Rv
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Gg'<Q.H
httpConnection.setRequestProperty("User-Agent","NetFox"); D!c1;IHZ
String sProperty = "bytes="+nStartPos+"-"; \nrgAC-b
httpConnection.setRequestProperty("RANGE",sProperty); G`9cd\^
Utility.log(sProperty); w9/nVu
:U!'U;uQ
@X3 gBGY)
InputStream input = httpConnection.getInputStream(); N[#iT&@T}/
//logResponseHead(httpConnection); N>Vacc_[
JZWgr&O<
s"pR+)jf1D
byte[] b = new byte[1024]; 6F@zCv"w
int nRead; $&ex\_W
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) ^2C0oX
{ e} sc]MTM
nStartPos += fileAccessI.write(b,0,nRead); JRHf.?
//if(nThreadID == 1) NFrNm'v
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); HiQoRk
} `G_(xN7O
pe\Txg6
MV Hz$hyB
Utility.log("Thread " + nThreadID + " is over!"); +A]&AkTw
bDownOver = true; _#/!s]$d#
//nPos = fileAccessI.write (b,0,nRead); g4~X#}:z$O
} t}5'(9
catch(Exception e){e.printStackTrace ();} f?/|;Zo4
} Kj~>&WU
} A8_\2'b
-&qRo0^3
w/lXZg
//打印回应的头信息 J0IdFFZ|w
public void logResponseHead(HttpURLConnection con) )![f\!'PI
{ d[s;a.
for(int i=1;;i++) Q\&AlV
{ aX>4Tw
String header=con.getHeaderFieldKey(i); b5iIV1g
if(header!=null) &LCUoTzj
//responseHeaders.put(header,httpConnection.getHeaderField(header)); #Pb7EL#c
Utility.log(header+" : "+con.getHeaderField(header)); sf.E|]isW
else X";QA":
break; :0J-ek.;
} adRNrt*!
} (&9DB
Y(#d8o}}#
xWC\954
public void splitterStop() 4=?Ok":8
{ EWuiaw.
bStop = true; Z-? Iip{
} O4b-A3:
S7Iu?R_I
#`N6<nb
} *sc0,'0
>6.[i@RmWU
3/A[LL|
/* g6[/F-3Qlf
**FileAccess.java 5CH-:|(;=
*//文件访问(定位，写) =0@d|LeZ
package NetFox; 4y]:Gqz~
import java.io.*; JR? )SGB
]AFM Y<mB
RAD4q"}k
public class FileAccessI implements Serializable{ 8ACYuN\
>'2w\Uk~:
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 t]u(jX)
RandomAccessFile oSavedFile; 7{kpx$:_
long nPos; H/^TXqQ8
Rktn/Vi
}0Kqy;
public FileAccessI() throws IOException 6'No4[F 4n
{ }(g+:]p-
this("",0); {P<BJ52=
} Zs3]|bUR
_Pfx_+
:~0^ib<v;
public FileAccessI(String sName,long nPos) throws IOException (Qh7bfd
{ $3]E8t
oSavedFile = new RandomAccessFile(sName,"rw"); ) v[Knp'
this.nPos = nPos; z!1/_]WJ,
oSavedFile.seek(nPos); LjH&f 4mY
} LDi ezi
yZ?_q$4kEI
:)J~FVLy
public synchronized int write(byte[] b,int nStart,int nLen) :#W>SO
{ @k:f}-t
int n = -1; Z:B Y*#B
try{ !s[j1=y
oSavedFile.write(b,nStart,nLen); .2{C29g
n = nLen; 32-3C6f@oZ
} "-j@GCme
catch(IOException e) tEWj}rX
{ QkCoW[sn
e.printStackTrace (); &J&w4"0N'
} $Op/5j
I^(o3B
dV2b)p4J
return n; A]SB c2
} MBYD,v&
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fssL'DD
} YI),q.3X~
]O9f"cj
_KkVI7a
/* qYu!:xa8
**SiteInfoBean.java 0.Ol@fO
*/ J*lYH]s
package NetFox; #u=O 5%.
]kplb0`
CIik@O*
public class SiteInfoBean { l& ^B
p_40V%y^
k}0
private String sSiteURL; //Site's URL $E~Lu$|
private String sFilePath; //Saved File's Path ]'ApOp
private String sFileName; //Saved File's Name $ p1EqVu
private int nSplitter; //Count of Splited Downloading File wPO@f~[Ji
lSbM)gL
l;VGJMPi
public SiteInfoBean() Jp*AIj
{//nSplitter的缺省值为5 }?qnwx.
//default value of nSplitter is 5 -JO46 #m
this("","","",5); C<=p"pWw
} N8(x),
z` ?xS
6=lQT 9u{
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) "yq;{AGOGl
{ "u]Fl+c
sSiteURL= sURL; 4aGpKvW
sFilePath = sPath; _C8LK.M#j
sFileName = sName; 5F+ f'~
this.nSplitter = nSpiltter; 1:s~ ]F@
%mvx}xV
?&nz
} l45F*v]^
dZYJ(7%
vHe.+XY
public String getSSiteURL() cWy0N
{ N)y;owgo
return sSiteURL; )3\rp$]1
} zw9ULQ$#
h?tV>x/Fu
$`{q =
public void setSSiteURL(String value) g#3x)97Z
{ 95&sFT C
sSiteURL = value; IX3yNTW"L
} L`@&0Zk
2m}]z.w#
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public String getSFilePath() 9>, \QrrH
{ h4xdE0
return sFilePath; .shI%'V
} `fVA.%
>Nqkz?67
Z{)|w=
public void setSFilePath(String value) L| qY
{ j*\MUR=
sFilePath = value; n!orM5=:O
} ~i {)J
-/*{^[
*g.,[a0
public String getSFileName() ht!:e>z&4
{ fP*C*4#X
return sFileName; ~t$VzL1
} }z@hx@N/
Qd=/e pkm
XwGJ 8&N
public void setSFileName(String value) 05DtU!3O
{ , >6X_XJQ
sFileName = value; PSvRO%&
} _J`M>W)8
UcIR0BYa
VAz+J
public int getNSplitter() e=C,`&sz
{ A]slssE+
return nSplitter; g-`NsqzD
} }zLE*b,
^`9OA`2
z#ET-[I
public void setNSplitter(int nCount) EkPSG&6RZ
{ WocFID:b
nSplitter = nCount; q9Wtu7/
} 6 >2! kM7
} T~d';P
^Y!`wp2vn
D-/A>
/* ^B>6!
**Utility.java &'j77tqOk
*/ T!AQJ:;1
package NetFox; b ;b1V
"^%Il
^8*.r+7p
public class Utility { epePx0N%x$
1,,:4*)
#Ki@=*
public Utility() hHQt4 r'd
{ #-O4x`W>
5VS<I\o}
{0~ p"%*
} $MR4jnTT
Ea1>]V
//线程睡眠 [VHt#JuN,
public static void sleep(int nSecond) +yk>jx
{ mD:!"h/
try{ 2TO1i0
Thread.sleep(nSecond); N[%IrN3
} %\u>%s<9
catch(Exception e) -b<+Ra
{ ]H*=Z:riu
e.printStackTrace (); hi%>&i*
} 7UiU3SUcg
} F$v G=3
+VDB\n
//日志 uFgw eOJ
public static void log(String sMsg) ~EymD *
{ >2r/d
System.err.println(sMsg); kBkhuKd)V
} 4?cg6WJ'6
bk2vce&
43YusUv
public static void log(int sMsg) 5 X rn]
{ oz QL2
System.err.println(sMsg); !|]%^G
} 2zAS \Y
} !q?}[E2
l%fl=i~oN
fjf\/%
/* >dO^pDSs
**TestMethod.java o_S8fHqjt
*/ 6b0#z#E
package NetFox; UaB!,vs3st
JL1Whf
gBN;j
public class TestMethod { Yd9y8TqJ
D<:9pLD(
gs'(px
public TestMethod() 1*s Lj#
{ ///xx/weblogic60b2_win.exe BX?Si1c
try{ }Q*8QV
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); -Rmz`yOq}
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); K.k=\N
SiteFileFetch fileFetch = new SiteFileFetch(bean); #u>JCPz
fileFetch.start(); :jA~zHO
} 0I,-1o|s
catch(Exception e){e.printStackTrace ();} F"_SCA?9?
F2#^5s(
*5 5yF`
} hTF]-& hZ
jl@xcs]#
tH$Z_(5
public static void main(String[] args) h_J'dJS
{ ]cbY@U3!2
new TestMethod(); 3*ZE``
} P*_Q8I)Y
} |[0|j/V%O
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