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)); |P"kJ45
} 1Dm$:),^T}
for(int i=0;i<nEndPos.length-1;i++) HxShNU
{ ({t6Cbw
nEndPos = nStartPos[i+1]; 0mT.J~}1v
} qUNXT
nEndPos[nEndPos.length-1] = nFileLength; %B#8
} {<Vw55)#0Q
} h`:gMhn
@%As>X<3t
,xC@@>f
//启动子线程 =NL(L
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; wIQt f|ZI>
for(int i=0;i<nStartPos.length;i++) M0MvOO*ad
{ DM !B@
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Y#Pg*C8>8
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), W'C~{}c=
nStartPos,nEndPos,i); ^<e(3S:
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ~,84E [VV
fileSplitterFetch.start(); 2MKB(;k
} 9C1\?)"D^e
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), ]*AQT7PH
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); !2g*=oY
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", -sk!XWW+
nEndPos = " + nFileLength); #Ic-?2Gn4<
// fileSplitterFetch[nPos.length-1].start(); ~w$ ^`e!]
TC._kAm
;[j)g,7{
//等待子线程结束 %t,Fxj4F
//int count = 0; AhSN'gWpbF
//是否结束while循环 Dn.%+im-u
boolean breakWhile = false; Y X{F$BM
A!`Q[%$
hQbz}x
while(!bStop) RMxFo\TK;
{ K!SFS
write_nPos(); +C[%^G-:
Utility.sleep(500); $%3%&+z$I
breakWhile = true; ,y*|f0&"~
$[*<e~?
DqBiBH[%h
for(int i=0;i<nStartPos.length;i++) J?bx<$C@
{ CF@j]I@{
if(!fileSplitterFetch.bDownOver) 8}!WJ2[R
{ hdH}4W
breakWhile = false; /.[78:G\,
break; n]P,5
} ]hi5nA
} WQYw@M~4Q!
if(breakWhile) e[L%M:e9U
break; #uH%J<U
(wZ/I(4
S8)6@ECC
//count++; T [2l32
//if(count>4) i~EFRI@
// siteStop(); MJI`1*(
} &BJ"T
8A2_4q@34
^1,VvLA+
System.err.println("文件下载结束！"); HO9w"){d$
} `"qSr%|
catch(Exception e){e.printStackTrace ();} nHF%PH#|o
} IkJ-*vI6
]*vv=@"`e
4xD`Z_U
//获得文件长度 59M\uVWR
public long getFileSize() a}/A]mu
{ @ZGD'+zd?
int nFileLength = -1; uBfSS\SX|
try{ UrEfFtH'
URL url = new URL(siteInfoBean.getSSiteURL()); rl](0"Y0 t
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 6Y&`mgMF'
httpConnection.setRequestProperty("User-Agent","NetFox"); jZ>x5 W
F>[T)t{m=
NuC+iC$_/
int responseCode=httpConnection.getResponseCode(); {:c5/ ,7c;
if(responseCode>=400) |#`qP^E
{ me&'BQ
processErrorCode(responseCode); JY6^pC}*
return -2; //-2 represent access is error :c`Gh< u
} vAjvW&'g
O p,_d^
|tuh/e@dx
String sHeader; q!\4|KF~
bGe@yXId5
aLt2fB1)
for(int i=1;;i++) 4 oZm0
{ :[.**,0R
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 'yR)z\)
//Utility.log(in.readLine()); =/MA`>
sHeader=httpConnection.getHeaderFieldKey(i); jdAjCy;s!
if(sHeader!=null) BXB ZX@jVk
{ #8qhl
if(sHeader.equals("Content-Length")) q=`i
{ "TP^:Ln
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); GEUC<bL+
break; 8zzY;3^h;
} `(o:;<&3
} -]kvM
else zX}t1:nc
break; h3t);}Y}D9
} rki0!P`
} }*s`R;B|,
catch(IOException e){e.printStackTrace ();} ![9umsx
catch(Exception e){e.printStackTrace ();} EohvP[i
CWw#0
b ]u01T-
Utility.log(nFileLength); %+HZ4M+hV
$u P'>
85Red~-M
return nFileLength; XsbYWJdds
} `A ^
ME.a * v
\2!1fN
//保存下载信息（文件指针位置） ;Bwg'ThT
private void write_nPos() {Bw
{ (rm*KD"]
try{ l~Rd\.O
output = new DataOutputStream(new FileOutputStream(tmpFile)); yr/G1?k%ML
output.writeInt(nStartPos.length); S^T ><C
for(int i=0;i<nStartPos.length;i++) ]-"G:r
{ d=d*:<Zx
// output.writeLong(nPos); lgQ"K(zY
output.writeLong(fileSplitterFetch.nStartPos); chA7R'+LA
output.writeLong(fileSplitterFetch.nEndPos); Xli$4 uL
} BnUWg ^E
output.close(); W!t=9i
} ble[@VW|
catch(IOException e){e.printStackTrace ();} -+{<a!Nb
catch(Exception e){e.printStackTrace ();} U'k 0;
} fs\A(]`$
dTZ$92<
c8Je&y8
//读取保存的下载信息（文件指针位置） aI;-NnC
private void read_nPos() h5<eU;Rw+
{ G4](!f!Kv
try{ h0a|R4J
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); D0^h;wJ=4+
int nCount = input.readInt(); :T )R;E@
nStartPos = new long[nCount]; WT63ve
nEndPos = new long[nCount]; )k.}>0K |
for(int i=0;i<nStartPos.length;i++) 5XoM)
{ 5y8VA4L/o
nStartPos = input.readLong(); c*.-mS~Z`
nEndPos = input.readLong(); D9h
} yQ0:M/r;0
input.close(); Q@KCODi
} we8aqEomr
catch(IOException e){e.printStackTrace ();} ?kdan
catch(Exception e){e.printStackTrace ();} Kv9Z.DY
} 6GA+xr=
ir|c<~_=
Kk`LuS?
private void processErrorCode(int nErrorCode) %X|u({(zb
{ ?W2u0N
System.err.println("Error Code : " + nErrorCode); +}R#mco5K
} +\]Gu(z<
)M><09
7YFEyX10d
//停止文件下载 \{ve6`7Rn
public void siteStop() #MFIsx)r
{ #/Bg5:
bStop = true; Bmt^*;WY+
for(int i=0;i<nStartPos.length;i++) 6=:s3I^
fileSplitterFetch.splitterStop(); `I.pwst8i-
@;\0cEn>
Q_>W!)p Gz
} rCUGaf~
} nF B]#LLv
//负责部分文件的抓取 MXiQWg$
**FileSplitterFetch.java h0$Y;=YA
*/ 6EeO\Qj{
package NetFox; eG7Yyz+t$
9l(T>B2a
vUCmm<y
import java.io.*; ]I_*+^?tI
import java.net.*; aW-6$=W
:V1j*)
tI)|y?q
public class FileSplitterFetch extends Thread { .cm2L,1h
"VDMO^
u'nQC*iJb
String sURL; //File URL $,P:B%]
long nStartPos; //File Snippet Start Position J$5Vjh'aM
long nEndPos; //File Snippet End Position %&S9~E D
int nThreadID; //Thread's ID 2VzYP~Jg
boolean bDownOver = false; //Downing is over 2+_a<5l~
boolean bStop = false; //Stop identical df!i}L
FileAccessI fileAccessI = null; //File Access interface ^t:dcY7
2RQ-L
P0pBR_:o
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException F$bV}>-1k
{ 7[PEiAI
this.sURL = sURL; C;j&Vbf
this.nStartPos = nStart; stUUez>
this.nEndPos = nEnd; |{v#'";O:
nThreadID = id; $,yAOaa
fileAccessI = new FileAccessI(sName,nStartPos);//定位 gB~^dv {
} ?~b(iZ
C]p@7"l
/'VbV8%
public void run() 0(*L)s,5
{ ;tSAQ
while(nStartPos < nEndPos && !bStop) j+@3.^vK
{ `BVmuUMm
]f0OmUHR5i
7i!VgV
try{ !I.}[9N
URL url = new URL(sURL); Vd(n2JMtG
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); \ 'Va(}v
httpConnection.setRequestProperty("User-Agent","NetFox"); { :1XN
String sProperty = "bytes="+nStartPos+"-"; 'ZB^=T
httpConnection.setRequestProperty("RANGE",sProperty); ()48>||
Utility.log(sProperty); &gPP#D6A
&O^-,n
[q Uv|l1
InputStream input = httpConnection.getInputStream(); vxHFNGI
//logResponseHead(httpConnection); U(#JC(E-#
iGkysU<wcp
0EF~Ouef
byte[] b = new byte[1024]; (|F.3~Amq
int nRead; &7oL2Wf
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) 7[w<v(Rc
{ &a;?o~%*]i
nStartPos += fileAccessI.write(b,0,nRead); vENf3;o0
//if(nThreadID == 1) M(zZ8#
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); ZXGi> E
} QW$p{ zo
l<BV{Gl
!1fZ7a
Utility.log("Thread " + nThreadID + " is over!"); ),-gy~
bDownOver = true; QeG9CS)E}j
//nPos = fileAccessI.write (b,0,nRead); |?ssHW
} HC/z3b;
catch(Exception e){e.printStackTrace ();} !3Pbu=(cte
} !Av9?Q:
} U(9_&sL
^:]$m;v]
6tndC o;`
//打印回应的头信息 ,|B-Nq
public void logResponseHead(HttpURLConnection con) H#DvCw
{ 8'HS$J;C
for(int i=1;;i++) {eV8h}KIl
{ `/ayg:WSU
String header=con.getHeaderFieldKey(i); P/girce0
if(header!=null) hd u2?v@
//responseHeaders.put(header,httpConnection.getHeaderField(header)); i5t6$|u:&m
Utility.log(header+" : "+con.getHeaderField(header)); f+Sb>$
else -~|{q)!F
break; c#sHnpP
} YT Zi[/
} o]Rlivahm
qQi\/~Y[:
4]uj+J
public void splitterStop() eM:J_>7t
{ Iz5NA0[=2
bStop = true; 8v4 o+wP
} #5Z`Q^
X 3$ W60Q
'Vo8|?.WhX
} S k~"-HL|
CMaph
52dD(
/* ylKK!vRHT
**FileAccess.java v$W[(
*//文件访问(定位，写) J6AHc"k.
package NetFox; `(sb
import java.io.*; R<Lf>p>_
`daqzn
ksOGCd^G7
public class FileAccessI implements Serializable{ \ph.c*c
A913*O:\
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 o)/Pr7Qn
RandomAccessFile oSavedFile; !qj[$x-ns
long nPos; <4"-tYa
ds(?:zx#
^taN?5
public FileAccessI() throws IOException 6:]N%
{ l9Ir@.m
this("",0); @#)` -]g
} Dj&~x
kg[%Q]]
/Hyz]46
public FileAccessI(String sName,long nPos) throws IOException ^Tm`motzh
{ Ki\.w~Qs
oSavedFile = new RandomAccessFile(sName,"rw"); 8Ojqm#/f
this.nPos = nPos; _U<fS
oSavedFile.seek(nPos); /|1p7{km
} :oP LluW*
:TH cI;PG8
tcuwGs>_
public synchronized int write(byte[] b,int nStart,int nLen) U]iI8c
{ QO/0VB42
int n = -1; f'^uuO#x
try{ d,b4q&^X8
oSavedFile.write(b,nStart,nLen); 5^u$zfR
n = nLen; ?pTX4a&>
} D(#f`Fj;
catch(IOException e) G@[8P?M=Z
{ 5&&4-
e.printStackTrace (); _h~ksNm5u
} 0=j }`
lW&(dn)}
~2w&+@dV%
return n; +jGHR&A t
} /SD}`GxH
cqS :Zq
{ALEK
} nqcq3o*B
W)In.?>]W
Ke\\B o,
/* AK2Gm-hHK
**SiteInfoBean.java 6pt_cpbR
*/ L*(9Hti
package NetFox; hmO2s/~
_M&TT]a
= xO03|T;6
public class SiteInfoBean { C82_)@96
&O&HczO
k$w~JO!s
private String sSiteURL; //Site's URL EKwQ$?I
private String sFilePath; //Saved File's Path I0Pw~Jj{
private String sFileName; //Saved File's Name M&Ka^h;N
private int nSplitter; //Count of Splited Downloading File LVj1NP
2$JGhgDI
4Gc M
public SiteInfoBean() #z*,CU#S9d
{//nSplitter的缺省值为5 ti\ ${C3
//default value of nSplitter is 5 1 em,/>"
this("","","",5); za>UE,?h
} t]yxLl\
tE7jTe
m&UP@hUV-
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) zM9#1^X
{ =)[m[@,c
sSiteURL= sURL; =q4}(
sFilePath = sPath; HN5m%R&`
sFileName = sName; I"07x'Ahq3
this.nSplitter = nSpiltter; ^\\3bW9}H
(#Y~z',I
Da=EAG-{7
} A6N6e\*
XE}gl&\
kRp]2^}\s\
public String getSSiteURL() 22`^Rsb,6L
{ x84!/n^z
return sSiteURL; -aoYoJ '
} 4T@:_G2b
_gvFs%J
;[v!#+yml
public void setSSiteURL(String value) R'Sd'pSDN
{ _C?j\Wy
sSiteURL = value; CdolZW-!"
} SepjF
K:PH:e
{i5?R,a)
public String getSFilePath() DBT4 W/
{ "g{q=[U}
return sFilePath; 1^~&"s U
} (o^tmH*
WJShN~ E
Y[ G_OoU
public void setSFilePath(String value) ]K=#>rZrB
{ ( ;FxKm<P@
sFilePath = value; DJP6Z
} 2;}leZ@U
^|Ap_!t$;
m5\T,
public String getSFileName() hnnB4]c
{ 0Y.z
return sFileName; `zd,^.i5~
} vCzZjGBY
)`u17 {
KII{GDR]
public void setSFileName(String value) a:kAo0@":j
{ D31X {dJ
sFileName = value; VF%QM;I[Rc
} A~zn;
MqyjTY::Xg
P}bIp+
public int getNSplitter() LCF}Y{
{ j]u!;]
return nSplitter; \Z-th,t
} y7Po$)8l
3uL f0D
>p_W(u@ z$
public void setNSplitter(int nCount) Wn%P.`o#
{ _jWs(OmJ
nSplitter = nCount; XlmX3RU
} B}e/MlX3M
} nzq
rTPgHK]?l
~?ab_CY
/* ^7gGtz2
**Utility.java zj 6I:Qr
*/ &i#$ia r
package NetFox; _y@28t
Y]z :^D
<r%K i`u(p
public class Utility { +;N]34>S7
Q@D7\<t
VtBC~?2U)B
public Utility() YIQD9
{ d?,'$$aB
xc^@"
~#_~DqbMZ5
} :@A&HkF
Y },E3<
//线程睡眠 /K=OsMl2b8
public static void sleep(int nSecond) u4x-GObJM
{ S{c/3k~
try{ *a9cBl'_
Thread.sleep(nSecond); *"%TAe7?~+
} bJd|mm/v
catch(Exception e) =i/Df?
{ {)YbksrJ{
e.printStackTrace (); @rl5k(
} r- 8Awa
} 7!O"k#
Z,&O8Jelf
//日志 |OeyPD#
public static void log(String sMsg) r\NqY.U&
{ :F(4&e=w
System.err.println(sMsg); lqDCK&g$E#
} Xs03..S
Tz @<hE
``MO5${
public static void log(int sMsg) K'A+V
{ 3efOgP=L
System.err.println(sMsg); Cxf K(F
} ~7m`p3W@
} -y`Pm8
;6tra_
_l d.Xmvd
/* c_/BS n
**TestMethod.java 5Rbl.5.A
*/ FP@_V-
package NetFox; N$fP\h^AR
$BqiC!~
(tK_(gO
public class TestMethod { sh/,"b2!P
qv!(In>u
K#3^GB3P
public TestMethod() :1'
{ ///xx/weblogic60b2_win.exe 7Cz~nin>7
try{ 26V6Y2X
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); T(!1\TB
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); pdu1 kL
SiteFileFetch fileFetch = new SiteFileFetch(bean); u[a-9^&g
fileFetch.start(); Nr|Gw @+
} Z{8%Cln
catch(Exception e){e.printStackTrace ();} RdCGK?s
aDS:82GMQ
lrrTeE*
} *G"hjc$L
]LE,4[VxRz
1k[_DQ=^l1
public static void main(String[] args) Z+xkN
{ <ZC.9
new TestMethod(); Kz'GAm\
} ,&[o:jTk
} I4Do$&9<D
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